Saturday, August 30, 2008
They include poverty and economic marginalization, poor nutrition, opportunistic infection, migration, sexual networking and patterns of sexual contact, armed conflict, and gender inequality. Some of these are discussed below.
Poverty as a key transmission factor:
The relationship between poverty and HIV transmission is not simplistic. It should be emphasized that poor segment of the population who are infected with HIV are considerably more likely to become sick and die faster than the non-poor since they are likely to be malnourished, in poor health, and lacking in health attention and medications.
In effect, all factors, which predispose people to HIV infection, are aggravated by poverty, which creates an environment of risk;
1. Deep-rooted structural poverty, arising from such things as, land ownership inequality, ethnicity and geo-graphical/political isolation, and lack of access to services.
2. Developmental poverty, created by unregulated socio-economic and demographic changes such as rapid population growth, environmental degradation, rural-urban migration, community dislocation, slums and marginal agriculture.
3. Poverty created by war, civil unrest, social disruption and refugees. High levels of rape and the breakdown of traditional sexual mores are associated with military destabilizations, refugee crisis and international influences on local communities.
All three have severe effects on individuals’ and communities’ vulnerability to the spread of HIV, their ability to handle risks, and opportunity to participate in prevention and care activities. The experience of HIV/AIDS by poor individuals, households and communities is likely to lead to an intensification of poverty, push some non-poor into poverty and some of the very poor into destitution. In turn, poverty can accelerate the onset of HIV/AIDS and tends to exacerbate the impact of the epidemic. Thus, as a result of the effect on mortality, morbidity, life expectancy and population growth, HIV/AIDS is having a direct negative impact on poverty, especially as experienced by poor rural households. In the 2001 report on the Special Session of the General Assembly on HIV/AIDS, the United Nations Secretary-General warned that HIV/AIDS was reversing decades of development in the hardest-hit regions of the world:
HIV/AIDS changes family composition and the way communities operate, affecting food security and destabilizing traditional support systems. By eroding the knowledge base of society and weakening production sectors, it destroys social capital. By inhibiting public and private sector development and cutting across all sectors of society, it weakens national institutions. By eventually impairing economic growth, the epidemic has an impact on investment, trade and national security, leading to still more widespread and extreme poverty. The most devastating consequences of HIV infection arise not simply because many people will die but because the deaths will occur mainly among adults between the ages of 25 and 45 years, the very people who work to support families and should be most productive economically. Therefore HIV/AIDS is changing the contours and dynamics of poverty through its demographic and socio-economic impacts, which may:
•Create inter-generational poverty by impoverishing surviving orphans (often forcing them out of school, thus limiting their livelihood options), by fragmenting or dissolving households and by decimating the fragile asset base of the poor;
•Alter the age structure and composition of the poor, by decimating the young adult population while impoverishing an increasing number of children and elderly people;
•Result in irreversible survival mechanisms for the poorest as what is to some extent unique about HIV/AIDS is that the shock it inflicts is one from which many households are unable to recover. In particular, the erosion of the household asset base tends to be permanent;
•Intensify discrimination and marginalization of poor people living with HIV/AIDS as well as their families. This is especially the case with women who are often perceived to be responsible for transmitting the HIV virus;
•Increase the prevalence of poor female-headed households (young widows with small children as well as elderly grandmothers looking after grandchildren) and thus the feminization of poverty and agriculture;
•Exacerbate unequal asset distribution (land, livestock, labor) leading to landlessness and de-stocking. Once land and livestock are sold, the recovery potential of these households is severely diminished. Destitution is the culmination of this process of asset depletion; and
•Intensify poverty-driven labor migration as a coping strategy, thereby increasing the risk of HIV infection among the survivors.
As often is the case, many of these strategies involve people migrating from their homes to other places, usually urban or rural centers, where they hope to find employment. For some women, the pressures of poverty may lead them to engage in sexual transactions in order to support themselves. Therefore migration and commercial sex work are two activities closely associated with risk for HIV infection, two issues that require closer elaboration as they often form central options in the multiple livelihood strategies developed by rural households.
The conceptualization of the factors contributing to the spread of the epidemic and linking it to issues such as poverty, migration in search of labor, income inequalities, and gender relations are crucial to an understanding of HIV/AIDS and its impact on society and the household in particular. From the discussion it is clear that poverty increases vulnerability to HIV infection and poverty is compounded by HIV/AIDS. The latter is a result of the shocks, which result from HIV/AIDS-related deaths and infection that intensify the usual problems associated with severe poverty. As a result, options such as commercial sex work that affected households may be forced to adopt in the face of the epidemic and increasing levels of poverty becomes inevitable. This indicates the need for a more focused discussion around the household and the multiple livelihood strategies that are constituted for survival in an increasingly difficult economic context.
HIV/AIDS and its impact on the Economy:
Economies tend to react more dramatically to economic restructuring than to long, slow corrosions as those wrought by AIDS. However, it is clear that the epidemic has profound implications for economies in affected regions as primary wage earners and caretakers fall sick, require care, and eventually dies, usually consisting of individuals of prime working age.
Macro-Economy and HIV/AIDS:
The impact of HIV/AIDS on the macro economic environment takes two dimensions, namely the direct and indirect costs. The former refers to the cost of treatment associated with HIV related illness, which has serious implications for health care budgets around the region. Those segments of the population that are poverty-stricken stand to lose the most as pressures on the health budgets increases resulting in higher medical costs. Indirect costs are more difficult to measure as the refer to loss of value of production, the loss of current wages, the loss of the present value of future earnings, training cost of new staff, high staff turn-over, cost of absenteeism, higher recruitment costs, the drainage of savings, lower labor force; Lower labor productivity through absenteeism and illness; Cost pressures for companies through benefit payments and replacement costs; Lower labor income, as employees bear some of the AIDS-related costs; Increased private sector demand for health care services; Higher government expenditure on health care services amongst others.
It should be emphasized that the impact on human and social development will be much more profound than can be reflected in limited indicators such as GDP or per capita GDP. These impacts would be felt throughout the economy, from the macro-level to the household, particularly as wage opportunities become scarcer.
The impact of HIV/AIDS at the household level also negatively impacts on the macro-economic context. The repercussions of HIV/AIDS is felt most acutely at the household level, with the burden weighing most heavily on the poorest households, those with the fewest resources with which to cushion the economic impact. The burden of HIV/AIDS and other related consequences readily translates into an overall cost on national development and the macro economies of individual countries, a situation aggravated by the fact that the portion of the population most affected by HIV/AIDS is the most economically active.
Ownership or access to rural land is a key part of many families’ well-being and livelihood. It is, however, only a small part in some contexts: small-scale agriculture in many parts of the world has been shown over the past decades to have become impossible without inputs from labor migrant remittances. This indicates that rural livelihoods are complex and aimed at managing risk, reducing vulnerability and enhancing security and are therefore based upon environmental stability. It is therefore important to have a sense of both the role of land and the broader labor market and macro-economic environment, which often underpin the incomes within the rural economy and the diverse livelihood strategies. These all come under increasing pressure with the broad impact of HIV/AIDS.
**TO BE CONTINUED**
Friday, August 29, 2008
Human development is the end, economic growth the means. The purpose of wealth should be to enrich people's lives, to broaden people's choices and to enable every citizen, every child, every woman and every man to reach his or her full potential. But HIV has found a wealth of opportunities to thrive among tragic human conditions fueled by poverty, abuse, violence, prejudice and ignorance.
Social and economic circumstances contribute to vulnerability to HIV infection and intensify its impact, while HIV/AIDS generates and amplifies the very conditions that enable the epidemic to thrive. Just as the virus depletes the human body of its natural defenses, it can also deplete families and communities of the assets and social structures necessary for successful prevention and provision of care and treatment for persons living with HIV/AIDS. This is demonstrated by the estimated millions of people living with HIV/AIDS world wide, mostly in developing countries the reports suggest. And a sizable number of those infected die from HIV/AIDS and related illnesses yearly suggesting that the epidemic is not slowing down fast enough. The impact of HIV/AIDS extends beyond those living with the virus, as each infection produces consequences which affect the lives of the family, friends and communities surrounding an infected person.
The overall impact of the epidemic encompasses effects on the lives of multiples of the millions of people living with HIV/AIDS or of those who have died. Those most affected by HIV/AIDS are children. Children are affected by HIV/AIDS in ways that can diminish their childhoods and as a result limit choices and opportunities for successful survival throughout their lives.
The circumstances of an individual's life and their social context in family and community during childhood can increase the probability they will one day be exposed to, and infected by, HIV. In order to develop appropriate means of enabling and protecting people, either as children or as adults, against infection and the effects of HIV/AIDS, adequate and judicious attention needs to be given to the rights and realities of childhood.
Children living in poverty because of being orphaned due to HIV/AIDS or other related cases are especially prone to victimization and in most cases become an easy pray for traffickers- as commodities for sale in local and global sexual prostitution and pornography industries.
The roles that children fill as poor, hungry, exploited and abused human beings increase their vulnerability to HIV infection. This can occur directly through those activities known to be associated with transmission, or indirectly as when the earlier harm turns children into vulnerable adults. For example those with a history of childhood physical or sexual abuse have also been found in adolescence or adulthood to be more likely than non-abused peers to engage in behaviors that place them at high risk of HIV infection.
Poverty as among the Leading Promoters of HIV and AIDS:
Poverty is clearly a factor in the spread and impact of HIV/AIDS. The struggle to survive everyday overshadows attention and concern about a virus that does not demonstrate any immediate harm. HIV/AIDS is a distant threat until it has a visible presence manifested by illness and death. Poverty, in depriving people of access to health facilities, schools and media also limits their access to information and education on HIV/AIDS.
Poverty pushes families, often unaware of the risks, to send children into the work force or to hand them over to recruiters promising jobs in a distant place where, unprotected, they might be forced into a childhood of harsh labor or sexual abuse. When HIV/AIDS appears in an already impoverished household- there are limited means for response. The mortality rate is high, the impact is severe and the pressures and pain of poverty increases. As increasing numbers of infected young adults are unable to contribute to their communities through their work as parents, teachers, laborers, drivers, farmers, etc., entire economic and social structures of communities suffers and demands for services increase with fewer able people to provide them. And there comes the big danger of the whole society being wiped out. Although life-saving drug regimens have dramatically decreased mother-to-child transmission of HIV and have kept mothers well and alive longer in the industrialized countries, poverty and the lack of necessary medical infrastructure and services make them inaccessible in those places where they are most needed.
Many women who know that they have tested positive for HIV may have no choice but to breast feed their babies when clean water and formula are unobtainable, even though they risk transmitting infection to their babies. Without access to health care or a nutritious diet, infected infants often die before they are two or three years old. For those who survive longer, or the uninfected ones whose parents or guardians are incapacitated by HIV/AIDS, or those orphaned- childhood can be dramatically shortened in other ways.
The illness or death of parents or guardians because of HIV/AIDS can rob a child of the emotional and physical support that defines and sustains childhood. It leaves a void where parents and guardians once provided love, protection, care and support. Since HIV is often (but by no means always) transmitted to sexual partners, children are more likely to lose both parents to HIV/AIDS. Someone is needed to step into parental roles so that children can survive and develop into healthy and productive adults. Grandparents, aunts, uncles or other caring adults frequently assume responsibilities that enable children to remain in their homes or take them into their own families and households. However, where the infection rate is high or harsh social or economic conditions exist, adults may be unable to assume the additional responsibilities of these families and children affected by HIV/AIDS. Other barriers grow out of ignorance and social attitudes. Fear of discrimination leads to families keeping secret the knowledge of HIV infection and AIDS within the household rather than seeking help. Others seek help but are rejected or abandoned, even by family members, when they reveal the nature of the illness. Fear, discrimination, ignorance, and social stigma associated with HIV/AIDS, in addition to overwhelming demands on caring adults, leave children isolated with their grief and suffering while they watch parents and other loved ones die as the families languish.
In many families and communities the environment for healthy growth and well-being has been devastated by HIV/AIDS. Instead of receiving special care and assistance, childhood is spent providing care and assistance. Children become decision-makers, responsible for the social and economic future of the family, and fill these roles without the physical and emotional protection, guidance and support that, as children, they deserve. They may act like adults, but it cannot be forgotten that these are still children acting (heads of households) and are children whose childhoods have been impoverished by HIV/AIDS. In such households, all children are affected. The care that older siblings can provide for younger children is likely to be inadequate because of the increased poverty of the household and the lack of maturity and experience of the caretaker, leading to poor health, hygiene and nutrition; absence from school, and developmental delays. The loss of material, emotional and developmental support from an adult exposes children to the distress which results from lack of affection, insecurity, fear, loneliness, grief or despair. It limits the possibility of a successful childhood which, in turn, affects the future as adults.
Solutions that Address Reality:
The problems the children are facing are monumental but so is the HIV epidemic which weaves through us all. The social context cannot be ignored or neglected in efforts to contain the virus. If success in prevention, treatment and cure is ever going to reach the majority of the population of the world affected by HIV/AIDS, then the elimination of conditions which nurture and strengthen its hold on individuals and communities and which provide obstacles to prevention and care must be zealously sought.
Prevention is usually easier than cure and recovery not only in matters of physical health but in all ways that affect the total well being of persons. Opportunities that foster the well being of a person begin in the uterus and depend on long term support from others. This dependency and support must exist throughout childhood only diminishing as the child approaches adulthood equipped with the strength and skills for independence and self sufficiency. The lifelong well being of a person depends on opportunities for the development of strengths and skills during childhood.
Aiding and Protecting Development:
Sustainable development, simply stated as the continued ability to develop and provide for one's needs, is a concept that can be applied to individuals or societies. The process towards the sustainable development of a human being, childhood, takes place at the center of many interdependent layers of social structures. The first tier is most often the basic social unit of the family. Outside the boundaries of the family the child is enveloped in broader social components of the community - extended family, peer groups, school, social and religious organizations, work places, etc. The development of children is determined by the willingness and ability of family and community members to contribute to their successful survival and growth. In the most concrete ways this includes the provision of food, shelter, clothing, health care, schools and recreational opportunities. It also includes emotional needs such as love, security, guidance, and encouragement.
In much the same way the family or community which has not achieved sustainability is dependent on the willingness and ability of other social entities (the state, international) to provide support and assistance. At all levels the ability of each social entity to sustain itself and provide support for others is dependent on the ability of its individual members to contribute to the existing demands within the social group. Just as a family benefits from the contributions and achievements of individual members, so does the community or nation.
The provision of a full and productive childhood for the potential future contributors of any society is necessary for the continuation of that society's sustainable development.
Building on Existing Strength and Human Assets:
The provision of sustainable conditions which will decrease the vulnerability of all people to HIV infection requires cooperative efforts on all levels of society to provide for the healthy growth and development of children. Children, by necessity, require continued support, but they also possess enormous potential for growth and sustainability. Successful approaches have been developed which focus on increasing the ability of families and communities to care for their children. The following are examples of such approaches.
Community support groups:
For children and family members who are living with HIV and for uninfected family members and affected others, this can provide:
•a forum where family members, including children, can discuss concerns and ask questions
•opportunities for sharing information about available services
•a platform for speakers to discuss prevention, care and treatment
•a focus for educational activities
•a focus for mutual support and income generating projects
•a platform for community advocacy and activism.
Services and assistance:
To support families affected by HIV/AIDS in ways that enable them to stay together and maintain their home. Such services can be offered by a combination of formal and informal service providers, including government or privately supported agencies, and might include:
•health and nutritional support
•home health care providers
•Income generating projects or direct financial support.
Training for those in the community who interact with HIV/AIDS affected families, can allow more people to contribute to prevention and the provision of quality care, and to offer support to dying parents and their children in planning for the future. Such training can also reduce the fear and discrimination which result from misunderstanding and misinformation.
**TO BE CONTINUED**
Sunday, August 24, 2008
Infection by the human immunodeficiency virus (HIV) causes AIDS. It is spread primarily through sexual contact, and also through blood-to-blood contact, needle sharing among intravenous drug users or accidental inoculation during medical procedures by health care professionals, and in pregnant women, from mother to child. Seventy percent of HIV transmission occurs through sexual contact. Blood transfusions and blood products caused many infections in the early years of the epidemic, but screening procedures have nearly eliminated this risk in many countries in both developed and developing ones. A mother can spread the virus to a newborn during delivery and through breast feeding, however drug therapy is now available that can greatly reduce the risk to infants.
Risk factors include:
•Having unprotected sex (without using a condom) and having more than one partner, whether you are heterosexual or homosexual
•Having another sexually transmitted disease
•Using intravenous drugs and sharing needles
Avoiding all the above risk factors and staying healthy are among the only effective ways of preventing HIV/AIDS.
KNOWING YOUR STATUS:
It is important that everyone is a ware of their HIV-status and more seriously so if you suspect any of the above risk factors. It is recommended that an effort is made to visit any nearest health care facility so that you are aware of your status regarding the HIV infection. You may receive a "rapid test," which can give a result in 20 minutes. If the test is positive, then confirmatory tests will follow. If tests confirms as positive, at this point usually a Physician will want to know the CD4 count and viral load (an indication of the amount of virus present. This information, along with your symptoms, helps evaluate the stage of the disease and assists in determining the best course of treatment/care.
HIV tests may not be accurate immediately after infection because it can take up to 12 weeks for the body can develop antibodies against the virus. If infection is suspected and the test is negative, retesting may be needed to confirm the prior results. Individuals who test positive are advised to inform their sexual partners immediately so that they can also be tested. This goes along way to preventing the spread of the virus.
Treatment and treatment Options:
There are medications that slow the progression of HIV infection to full-blown AIDS. Generally, combinations of these medicines, including a type called protease inhibitors, are used. In addition, antibiotics and other therapies are used to prevent or treat specific complications.
Combinations of drugs are used in an effort to treat HIV very aggressively, with the aim of reducing the amount of virus in your blood to very low or undetectable levels, and to suppress symptoms for as long as possible.
Antiretroviral drugs help slow the progression of HIV by inhibiting the reproduction of the virus in the body. It's important to keep a steady dose of antiretroviral drugs in your system to prevent the virus from developing resistance to the drugs. Antiretroviral medications include:
•Protease inhibitors (PIs) stop an HIV enzyme from replicating. This class of drugs includes saquinavir (Invirase), nelfinavir (Viracept), ritonavir (Norvir), tipranavir (Aptivus), indinavir (Crixivan), amprenavir (Agenerase), and atazanavir (Reyataz). Other new ones includes; darunavir (Prezista), which is used in combination with other drugs for people who have not responding well to the treatment. A combination of ritonavir and lopinavir (Kaletra) is among the most prescribed protease inhibitors. Protease inhibitors are considered the most powerful of HIV drugs and often interact with other medications, so they must be monitored carefully and effectively.
•Nucleoside analogue reverse transcriptase inhibitors (NRTIs) also stop a particular HIV enzyme from replicating. These drugs were among the first to be developed and include zidovudine or azidodeoxythymidine (Retrovir or AZT), lamivudine (Epivir), didanosine (Videx), abacavir (Ziagen), stavudine (Zerit), and zalcitabine (Hivid). Emtricitabine (Emtriva) is a newer drug in this class and is taken with at least two other HIV medications. Combinations of several other drugs are also available. All have side effects that must be monitored carefully by your healthcare provider.
•Nucleotide reverse transcriptase inhibitors (NtRTIs) work similarly to NRTIs but act more quickly. So far there is only one drug in this class, tenofovir (Viread), which seems to be effective in people who develop resistance to NRTIs.
•Non-nucleoside reverse transcriptase inhibitor (NNRTIs) stops the virus from making DNA, so that it can't replicate itself. There are three drugs in this class: nevirapine (Viramune), efavirenz (Sustiva), and delavirdine (Rescriptor). They are often used if people cannot tolerate the side effects of protease inhibitors, want to delay protease inhibitor therapy, or if they have taken protease inhibitors but did not experience a drop in levels of the virus. Many of these drugs are cross-resistant, meaning that if you develop resistance to one drug in this class it's likely you will be resistant to all.
•Fusion inhibitors prevent the HIV membrane from fusing with the membrane of healthy cells in your body. Enfuvirtide (Fuzeon) is often used in combination with other drugs in people who have become resistant to other medications. It must be administered by injection.
In addition, any opportunistic infections are treated with the appropriate medications, or in some cases medications are given to prevent the infections from occurring (prophylaxis).
Complementary and Alternative Therapies:
Many people with HIV turn to complementary and alternative therapies to reduce symptoms of the virus, lessen side effects from medications, improve overall health and well-being, and for a sense of empowerment by being actively involved in their own care.
Different therapies are used to:
•Inhibit the virus
•Treat symptoms of the virus or side effects of medication
•Treat or prevent opportunistic infections
Since the major impact of HIV is that it leaves patients vulnerable to opportunistic infections, making adjustments to ensure your overall health through improving stress reduction, exercise, and building a social support network can significantly boost immune function. In fact, these actions are some of the most powerful tools a person has to impact the course of the disease.
Other changes, such as improving oral and general hygiene and limiting exposure to environmental pollutants, can also bolster your health and vitality. These small steps can add up to a longer and healthier life for many people.
However, HIV should never be treated with alternative therapies alone. It is extremely important that you share information on your use of complementary and alternative therapies with your healthcare provider, so that it can built on in helping you determine what is safe and appropriate.
Nutrition and Supplements:
Vitamin C can inhibit the virus in test tubes, although it has not shown the same effect in the human body. It can help boost the immune system, however. Very high doses of vitamin C are sometimes used as supportive therapy. The dose must be determined and monitored appropiately.
N-acetyl cysteine or NAC (800 mg per day), an amino acid, may also slow the growth of the virus in test tubes, though study results have been mixed on whether it reduces the level of virus in the body. It does help the body synthesize glutathione, an antioxidant found in the body that is often low in people with HIV or AIDS. NAC may also help with AZT side effects.
Because of the loss of appetite, people with HIV have low levels of some essential vitamins and nutrients, including:
•Vitamin A and beta-carotene -- these are often deficient in people with HIV, and low levels of vitamin A may be associated with lower CD4 counts. A high supplemental dose may be beneficial, but very high doses have been associated with higher death rates from AIDS. Your health care provider may help determine the proper dose for you, and, since high doses can also damage the liver, monitor your liver function.
•B-complex vitamins (75 - 100 mg per day). Low levels of vitamin B12 and B1 (thiamine) in people with HIV have been linked to lower CD4 counts and neurological problems. B6 deficiency has been associated with poor immune function. A type of B3 (niacinamide) seemed to slow the progression of HIV.
•Vitamin E (400 IU two times per day) may help reduce side effects of AZT while improving the drug's effectiveness, although evidence is slight.
•Selenium (100 - 400 mcg per day) needed for the immune system to function properly, and higher levels of selenium in the body may help boost CD4 counts. Some studies have shown results with 400 mcg per day. At this dose, however, it should be monitored by your health care provider.
•Zinc (45 mg per day) may boost the immune system and help prevent opportunistic infections, but there is also some evidence that zinc can be harmful for HIV infection. Talk to your healthcare provider to see if you are deficient in zinc before taking it.
•Iron is often deficient in people with HIV. Your doctor must determine and monitor the proper dose because too much iron can increase bacterial infections.
*All in all, it’s clear that nutrition and overall health of the whole body is important in remaining healthy and a good balanced diet regiment including regular exercise is not only of at most importance for healthy individual but also for those living with HIV infection.
Weight loss can be a serious problem for people with HIV. This symptom may begin early in the course of the disease and can increase the risk for developing opportunistic infections. Weight loss is exacerbated by other common symptoms of HIV and AIDS, including lesions in the mouth and esophagus, diarrhea, and poor appetite. Over the last several years, weight loss has become less of a problem due to the new protease inhibitors used for treating HIV. Reduction of muscle mass, though, remains a significant concern. Working with professionals in nutritional science can help in developing for example a meal plan to prevent weight loss and muscle breakdown is extremely helpful. Resistance training (lifting weights) can also protect against muscle breakdown and increase lean body mass.
Preventing diarrhea and ensuring that the body absorbs enough protein to maintain muscle strength has become a major goal of HIV/AIDS preventative care. One program for combating diarrhea includes using soluble fiber/and or foods that provides it. For some people, soluble fiber can help food stay in the digestive tract for longer periods of time, increasing the amount of nutrients that are absorbed, and lessening bowel frequency. Because diarrhea can be a potentially life-threatening situation, soluble fiber therapy should be used under the strict supervision of a trained professional.
Using certain supplements may help in maintaining body weight. A well-designed study compared the use of a daily supplement regimen that included enormous amounts of the amino acid glutamine (40 g per day), along with vitamin C (800 mg), vitamin E (500 IU), beta-carotene (27,000 IU), selenium (280 mcg), and N-acetyl cysteine (2,400 mg) to placebo. People who took the supplements gained significantly more weight after 12 weeks than those who took the placebo.
Another study found that a combination of glutamine (7 g per day), arginine (7 g), and an amino acid derivative called hydroxymethylbutyrate or HMB (1.5 g) helped people gain lean body weight during 8 weeks of treatment compared to placebo. High doses of arginine however, may be linked to an increase in herpes viral outbreaks. To find the right dose that offers benefits without dangerous side effects, consult with a trained nutrition professional.
Other supplements sometimes used for supportive treatment include:
•Dehydroepiandrosterone or DHEA (200 - 500 mg per day) is a hormone that is often low in people with HIV. One study found that DHEA supplements improved minor depression with no serious side effects. Because DHEA is a hormone, you should not take it without your doctor's supervision.
•Coenzyme Q10 (200 mg per day) appears to help improve immune system function and slow progression of the disease.
•SAMe or S-adenosyl-L-methionine (intravenous dose of 800 mg per day) is used to treat AIDS-related myelopathy (diseases that affect the spinal cord).
•Injections of vitamin B6 and B12 can dramatically improve neuropathies (damage to peripheral nerves) associated with some HIV medications such as Zerit.
You may use herbs as supportive therapies, but you should never use them alone to treat HIV or AIDS. It is important that you keep all of your health care providers informed of any treatments, conventional or alternative, that you are taking so they can monitor interactions and side effects, and provide the best care.
A few herbs have antiretroviral effects, though none are as effective at reducing the level of virus in your systme as conventional drugs. Herbs that have antiretroviral effects include:
•Boxwood (Buxus sempervirens) was studied before many conventional drugs were developed to treat HIV. A special extract of stems and leaves given in the amount of 990 mg per day slowed the progression of the disease and decreased levels of virus in the blood. No side effects were reported, although high doses of a substance found in boxwood can cause muscle spasms and paralysis. For that reason, and because only the extract of boxwood has been evaluated for HIV, you should only take boxwood under supervision.
•Licorice (Glycyrrhiza glabra) -- Two studies used an extract of licorice, which appeared to slow growth of the virus. Because the amounts used are high and large doses can have serious side effects including high blood pressure, you should only take licorice under supervision. Do not take licorice if you have high blood pressure, kidney disease, or heart failure.
•Turmeric (Curcuma longa, 1.5 - 3 g per day) -- Some test-tube studies suggest turmeric and its active ingredient curcumin can slow replication of the virus. In a human study, turmeric appeared to increase CD4 counts.
You may also use herbs to support the immune system. They may include:
•Andrographis ( Andrographis paniculata) -- A pilot study found that components of andrographis increased CD4 counts and decreased the amount of virus in the blood, but caused potentially dangerous side effects. Because of that, you should not take andrographis without supervision.
•Korean red ginseng or Asian ginseng (Panax ginseng) -- Several studies suggest Korean red ginseng has benefits, including raising CD4 counts and increasing the effectiveness of AZT. You may want to consult a trained practitioner in traditional Chinese medicine to assess whether ginseng will be beneficial for your individual constitution.
•Sangre de Drago (Croton lechleri, 500 mg every six hours) -- One study and anecdotal evidence suggest Sangre de Drago may be helpful in combating AIDS-related diarrhea. Because very high amounts of the herb were used, it should only be taken under supervision.
•Cat's claw (Uncaria tomentosa) -- In one study of 13 patients with human immunodeficiency virus (HIV) who refused to take conventional treatments, an extract of cat's claw at a dosage of 20 mg per day for up to 5 months significantly increased white blood cell counts (the infection-fighting cells in the body that HIV destroys). There is some preliminary indication that it may reduce side effects from AZT. However, there are also studies suggesting a negative result from cat's claw. You should consult a trained, botanically oriented professional before adding cat’s claw to your regimen, and all other health care providers should be aware of all your treatments.
Other herbs sometime used to treat symptoms of HIV or opportunistic infections include tea tree oil (Melaleuca alternifolia), which has been used to treat thrush (15 ml of solution used as a mouthwash), and garlic (Allium sativum), which has helped treat AIDS-related diarrhea and stop weight loss. Garlic interacts negatively with several HIV medications, however, so you should never use garlic without supervision.
No specific scientific research supports the use of homeopathy for HIV or AIDS. A licensed, certified homeopathic professional should do individual evaluation to assess the value of homeopathy for reduction of symptoms or side effects from medication as an adjunct to standard medical treatment.
Exercise is another way to help develop a general sense of well-being, improve mental attitude, decrease depression, diminish weight loss, and increase lean body mass. Resistance or weight training is particularly useful to increase strength and enhance lean body mass.
People with HIV have used acupuncture to improve general well-being, alleviate symptoms such as fatigue, insomnia, and night sweats, and to minimize side effects from medications, such as nausea. Some people also find relief from peripheral neuropathy, caused occasionally by certain medications used for HIV, reporting less pain, increased strength, and improved sensation.
As mentioned earlier, diarrhea can be a major problem for people with HIV throughout the world. In China, acupuncture and moxibustion (a heat treatment performed by the acupuncturist over points where the needles are placed) are the standard treatments for HIV-related diarrhea.
Acupuncture can also be used to treat the neuropathic (nerve) pain associated with certain HIV medications. Inserting needles bilaterally in the hand and foot points known as Baaxie and Bafeng, respectively, can lessen neuropathic pain.
Massage can relieve chronic muscle tension and stress, which may help the immune system.
HIV and Pregnancy:
HIV-positive pregnant mothers- taking certain antiretroviral medications may reduce the likelihood of transmitting the virus to the baby. Your healthcare provider should determine which medicine is best and safe for the baby. Depending on individual’s condition, a health care provider may decide to postpone treatment until after the first trimester to reduce the risk of birth defects. Breastfeeding should be avoided because of the risk of transmitting the virus to the baby.
**TO BE CONTINUED**
Saturday, August 23, 2008
Kenya’s 2008 Olympics: Top Medalists.
SPORT- MEDALS- ATHLETE- EVENT
Track &field: Gold- W.Bungei - Men’s 800m
Gold -P. Jelimo - Women’s 800m
Gold- N. Langat - Women’s 1500m
Gold -B. Kiprop Kipruto - Men’s 3000m
Gold -S. Wanjiru - Men’s Marathon
Silver- J. Jepkosgei - Women’s 800m
Silver- A. Kiprop - Men’s 1500m
Silver- E. jepkorir - Women’s 3000m
Silver- E. Kipchoge - Men’s 5000m
Silver- C. Ndereba - Women’s marathon
Bronze-A. Kirwa Yego- Men’s 800m
Bronze-R. Mateelong- Men’s 3000m
Bronze-E. Soi Men’s - 5000m
Bronze-M. Kogo - Men’s 10,000m
The total Medal haul from Beijing 2008 Olympics stands at 14;
5-Golds, 5-Silvers and 4-Bronze.
That brought Kenya’s Medals overall ranking at number 15th worldwide. Not a bad feat at all I would say! And For all the Men and Women, who sacrificed too much for our beloved country, let’s say, **ASANTENI SAANA! AND BRAVO**!
Sunday, August 17, 2008
HIV- (human immunodeficiency virus) belongs to the retrovirus family (HIV-1 and HIV-2). Retroviruses are unique because they possess the enzyme reverse transcriptase. Reverse transcriptase allows the viral RNA genome to be replicated into DNA, rather than the usual RNA copies. The HIV attacks the immune system, the body’s natural defense system. Without a strong immune system, the body is unable to fight any disease that it encounters.
Both the virus and the infection it causes are all together referred to as HIV infection. The virus takes over certain immune system cells to make many copies of its own (replication). While many viruses can be controlled by the immune system, HIV targets and infects that same immune system i.e. cells that are supposed to protect the body from illnesses. These are a type of white blood cell called CD4 cells. HIV takes over CD4 cells and turns them into virus factories that produce thousands of viral copies. As the virus grows, it damages or kills CD4 cells, weakening the immune system, thus causing slow but constant damage to the body’s natural defense system of which at this stage is commonly called AIDS.
The virus may be passed from one person to another when infected blood, semen, or vaginal secretions come in contact with an uninfected person’s broken skin or mucous membranes. In addition, infected pregnant women can pass HIV to their baby during pregnancy or delivery, as well as through breast-feeding. People with HIV have what is called HIV infection. Some of these people will develop AIDS as a result of their HIV infection.
AIDS – (Acquired Immunodeficiency Syndrome):
Acquired – means that the disease is not hereditary but develops after birth from contact with a disease causing agent (in this case, HIV).
Immunodeficiency – means that the disease is characterized by a weakening of the immune system.
Syndrome – refers to a group of symptoms that collectively indicate or characterize a disease.
In the case of AIDS this can include the development of certain infections and/or cancers, as well as a decrease in the number of certain cells in a person’s immune system.
Acquired Immune Deficiency Syndrome is a set of symptoms and infections resulting from the damage to the human immune systems caused by the (HIV). This condition progressively reduces the effectiveness of the immune system and leaves individuals susceptible to opportunistic infections and tumors. It is the condition diagnosed when there are a group of related symptoms that are caused by severe human immunodeficiency virus infection. AIDS makes the body vulnerable to life-threatening illnesses called opportunistic infections. But having HIV does not mean you have AIDS. Even without treatment, it takes a long time for HIV to progress to AIDS—usually 10 to 12 years. If HIV is diagnosed before it becomes AIDS, medicines can slow or stop the damage to the immune system. With treatment, many people with HIV are able to live long and active lives.
Immune system: (as pertains to the HIV/AIDS)
Your immune system is your body's natural defense against infection and illness. Specialized cells and organs all work in concert to protect your body and keeping your body away from diseases and thus healthy. Understanding these different parts of your immune system and how your immune system works will help to better understand HIV and AIDS. There will be more discussions dedicated to immune system in another entry.
Organs and Cells of the Immune System:
All the specialized cells of the immune system are formed in the bone marrow. Their formation is begun in bone marrow and then they move into the blood stream where they mature.
This small but important organ produces T-cells. In addition, the thymus actually chooses which T-cells are best suited for the immune system. The remaining ones are eliminated by the body, assuring a healthy, effective immunity.
You can think of the spleen as a filter for the blood. It catches foreign material in the blood and activates different types of immune system cells.
The lymph nodes filter foreign material from the lymph fluid. Fluid that drains from various tissues in the body collects in the lymph system and passes through the nodes, being filtered as it passes.
•Cells-Leukocytes or WBCs.
The leukocytes are further subdivided into granulocytes (containing large granules in the cytoplasm) and agranulocytes (without granules). The granulocytes consist of neutrophils (55–70%), eosinophils (1–3%), and basophils (0.5–1.0%). The agranulocytes are lymphocytes (consisting of B cells and T cells) and monocytes. Lymphocytes circulate in the blood and lymph systems, and make their home in the lymphoid organs. For the sake of the topic we'll consider T-cells here.
T-Cells also called CD4 Cells:
T-Cells- There are two subsets of T-cells: CD4 cells and CD8 cells. CD4 cells secrete factors that activate other white blood cells that participate in the immune response. HIV attacks CD4 cells, damaging the body's ability to initiate the immune response.
CD8 cells are important in directly killing tumor cells, viral infected cells and some parasites. T/CD4 cells are also called “helper” cells. And in other words lead the attack against infections. While the T-8 cells (CD8) are called “suppressor” cells that end the immune response. CD8 cells can also be “killer” cells that kill cancer cells and cells infected with a virus.
It is important for people who are HIV+ to know their CD4 cells count as this can give a picture of the effectiveness or the status of their immune system.
Knowing how many functioning CD4 cells are circulating in the blood gives an idea of how strong the HIV+ person's immune system really is. A CD4 cells count measures the number of functioning CD4 cells in the body and therefore measures the health of the immune system.
The CD4 test ranges vary but Normal Values - In a healthy adult is typically 600 to 1200 cells per cubic millimeter of blood. And Between 600 and 350 - In an HIV+ person is considered "very good". And Between 350 and 200 - The immune system is weakened and therefore the HIV+ person may be at increased risk for infection and illness.
Signs and Symptoms:
Symptoms of infection with HIV can vary. Often a flu-like syndrome occurs in 50 to 80% of those who contract HIV within the first 2 - 6 weeks, including a combination of the following symptoms:
•Swollen lymph nodes
After you are infected with HIV, you may remain relatively symptom-free for years or the disease may progress more rapidly. In this stage, the CD4 count may be below 500 per cubic millimeter. You may develop infections or chronic symptoms including:
•Swollen lymph nodes
•Cough and shortness of breath
•Low platelet count, which may manifest as easy bruising, bleeding gums, or nose bleeds
During the last stage of the disease, HIV infection may meet the official criteria for AIDS, which is the presence of an opportunistic infection (such as Pneumocystis carinii pneumonia, or PCP) or a CD4 count below 350-200 per cubic millimeter. At this stage, symptoms may include
•Pneumonia, including PCP
•Extreme weight loss and wasting, exacerbated by diarrhea. Up to 90% of HIV patients worldwide experience diarrhea
•Meningitis and other brain infections
•Malignancies such as lymphoma, cervical cancer, and Kaposi's sarcoma (KS) (affects the skin and oral mucosa and may spread to the lungs. KS can actually occur in earlier stages of HIV as well).
****TO BE CONTINUED****
Saturday, August 9, 2008
Hepatitis is a disease characterized by inflammation of the liver, usually producing swelling and, in many cases, permanent damage to liver tissues. A number of different agents can cause hepatitis, including infectious diseases, chemical poisons, drugs and alcohol. Viral hepatitis refers to a set of at least six viruses that are known to cause hepatitis: hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), hepatitis E (HEV), and hepatitis G (HGV). Recent scientific evidence also suggests the existence of other, as yet unidentified hepatitis viruses.
The most common types of viral hepatitis are hepatitis A, B, and hepatitis C. Both hepatitis B and C can lead to serious, permanent liver damage, and in many cases, death.
There are two primary types of viral hepatitis, food-borne and blood-borne hepatitis. The former, which is spread through contaminated food and water, does not cause chronic liver disease. By contrast, blood borne viral hepatitis may lead to long-term, persistent infections and chronic liver disease that has lethal consequences many years after infection.
Hepatitis A: is an acute liver disease caused by the hepatitis A virus (HAV), lasting from a few weeks to several months. It does not lead to chronic infection.
Transmission: Ingestion of fecal matter, even in microscopic amounts, from close person-to-person contact or ingestion of contaminated food or drinks.
Vaccination: Hepatitis A vaccination is recommended for all children starting at age 1 year, travelers to certain countries, and others at risk.
Hepatitis B: Is a liver disease caused by the hepatitis B virus (HBV). It ranges in severity from a mild illness, lasting a few weeks (acute), to a serious long-term (chronic) illness that can lead to liver disease or liver cancer.
Transmission: Contact with infectious blood, semen, and other body fluids from having sex with an infected person, sharing contaminated needles to inject drugs, or from an infected mother to her newborn.
Vaccination: Hepatitis B vaccination is recommended for all infants, older children and adolescents who were not vaccinated previously, and adults at risk for HBV infection.
Hepatitis C: is a liver disease caused by the hepatitis C virus (HCV). HCV infection sometimes results in an acute illness, but most often becomes a chronic condition that can lead to cirrhosis of the liver and liver cancer.
Transmission: Contact with the blood of an infected person, primarily through blood-blood/broken skin contact.
Vaccination: There is no vaccine for hepatitis C.
Hepatitis D- Is a serious liver disease caused by the hepatitis D virus (HDV) and relies on HBV to replicate.
Transmission: Contact with infectious blood, similar to how HBV is spread.
Vaccination: There is no vaccine for hepatitis D.
Hepatitis E- Is a serious liver disease caused by the hepatitis E virus (HEV) that usually results in an acute infection. It does not lead to a chronic infection. Hepatitis E is fairly common in many parts of the world.
Transmission: Ingestion of fecal matter, even in microscopic amounts; outbreaks are usually associated with contaminated water supply in regions with poor sanitation.
Vaccination: There is no currently approved vaccine for hepatitis E.
Although its means of transmission is fairly well documented, the hepatitis C virus itself largely remains a mystery. Hepatitis C is extremely small, even for a virus - it is only about 50 nanometers in diameter. A nanometer is one billionth of a meter - if you placed 200,000 hepatitis C viruses end to end, they would be only a single centimeter long. However, what is known about hepatitis C underscores the type of threat that it poses.
Hepatitis C is an RNA virus - which means that it mutates frequently. Once an infection has begun, hepatitis C creates different genetic variations of itself within the body of the host. The mutated forms are frequently different enough from their ancestors that the immune system cannot recognize them. Thus, even if the immune system begins to succeed against one variation, the mutant strains quickly take over and become new, predominant strains. As a result, the development of antibodies against HCV does not produce immunity against the disease like it does with most other viruses. More than 80% of the individuals infected with HCV will progress to a chronic form of the disease.
As a result of this, hepatitis C is usually not self-limited as a disease. In more than 85% of all cases, whether they progress to chronic liver disease or not, the infected individual carries the virus for life. This means that they also remain contagious for a lifetime, able to transmit the virus to others. And because of the long progression of the illness, even patients who will eventually die as a result of hepatitis C carry the virus for decades before it takes their lives. Most epidemics are self-limiting - they spread rapidly, but over a short period of time the affected population either dies or develops immunity to the disease, and it stops spreading. Not so with hepatitis C. Much like HIV and AIDS, it lasts a lifetime, and kills slowly - giving the virus plenty of time to spread.
There are six basic genotypes of HCV, with 15 recorded subtypes, which vary in prevalence in different regions of the world. Each of these major genotypes can differ significantly in their biological effects - in terms of replication, mutation rates, type and severity of liver damage, and detection and treatment options. However, these differences are not yet clearly understood.
The 21 current variations in genotype, complicated by the constant mutation of the virus within infected individuals, represents a major challenge for the development of treatments and vaccines against HCV - and even for reliable detection of the virus. There is no guarantee that a treatment, test, or vaccine against one strain will be effective against all of them. Moreover, individuals cured of one strain will be prone to re-infection by any of the other strains.
The infection is often asymptomatic, and can often lead to chronic infection and cause inflammation of the liver (chronic hepatitis). This condition can progress to scarring of the liver (fibrosis), and advanced scarring (cirrhosis). In some cases, those with cirrhosis will go on to develop liver failure or other complications of cirrhosis, including liver cancer. No effective vaccine against hepatitis C is available. The symptoms of infection can be medically managed, and a proportion of patients can be somewhat cleared of the virus by a course of anti-viral medicines. Although early medical intervention is helpful, people with HCV infection can experience mild symptoms, and consequently do not seek treatment. (Approximately 150-200 million or more) people are infected with hepatitis C world wide.
Although HCV is not known to efficiently be transmitted sexually, persons at risk for infection through injection drug use might seek care in STD treatment facilities, HIV counseling and testing facilities, prisons/and or correctional facilities, drug treatment facilities, and other public health settings where STD and HIV prevention and control services are available.
Sixty to 70% of persons newly infected with HCV typically are usually asymptomatic or have a mild clinical illness. HCV RNA can be detected in blood within 1–3 weeks after exposure. The average time from exposure to antibody to HCV (anti-HCV) seroconversion is 8–9 weeks, and anti-HCV can be detected in >97% of persons by 6 months after exposure. Chronic HCV infection develops in 70%–85% of HCV-infected persons; 60%–70% of chronically infected persons have evidence of active liver disease. The majority of infected persons might not be aware of their infection because they are not clinically ill. However, infected persons serve as a source of transmission to others and are at risk for chronic liver disease or other HCV-related chronic diseases decades after infection.
HCV is most efficiently transmitted through large or repeated percutaneous exposure to infected blood (e.g., through transfusion of blood from non screened donors or through use of injecting drugs). Although much less frequent, occupational, Perinatal, and sexual exposures also can result in transmission of HCV.
Since the clinical characteristics are similar for all types of acute viral hepatitis, the specific viral cause of illness cannot be determined solely on the basis of signs, symptoms, history, or current risk factors, but must be verified by specific serologic testing.
In most of the developed countries, the people at risks of HCV infection include; Current or former injection drug users, including those who injected only once many years ago, Recipients of clotting factor concentrates made before 1987 when more advanced methods for manufacturing those products were developed, Recipients of blood transfusions or solid organ transplants before July 1992 when better testing of blood donors became available, Chronic hemodialysis patients, Persons with known exposures to HCV such as health care workers after needle sticks involving HCV-positive blood recipients of blood or organs from a donor who tested HCV-positive Persons with HIV infection, Children born to HCV-positive mothers.
Is it possible for someone to become infected with HCV and then spontaneously clear the infection?
Yes. Approximately 15%–25% of persons clear the virus from their bodies without treatment and do not develop chronic infection; the reasons for this are not well known. HCV infection becomes chronic in approximately 75%–85% of cases.
Why most persons remain chronically infected with HCV?
A person infected with HCV mounts an immune response to the virus, but replication of the virus during infection can result in changes that evade the immune response. This may explain how the virus establishes and maintains chronic infection.
What are the chances of developing chronic HCV infection/liver disease, cirrhosis, or liver cancer or dying as a result of hepatitis C.?
For every 100 persons infected with HCV, approximately 75–85 will go on to develop chronic infection 60–70 will go on to develop chronic liver disease, 5–20 will go on to develop cirrhosis over a period of 20–30 years, 1–5 will die from the consequences of chronic infection (liver cancer or cirrhosis). And persons can become infected with a different strain of HCV after they have cleared the initial infection. Prior infection with HCV does not protect against later infection with the same or different genotypes of the virus. This is because persons infected with HCV typically have an ineffective immune response due to changes in the virus during infection.
For the same reason, no effective pre- or post exposure prophylaxis (i.e., immune globulin) is available. Currently there is no vaccine for hepatitis C available. Research into the development of a vaccine is still ongoing.
Transmission and Symptoms:
How HCV is transmitted:
HCV is transmitted primarily through large or repeated percutaneous (i.e., passage through the skin) exposures to infectious blood, such as Injection drug use. Receipt of donated blood, blood products, and organs (once a common means of transmission but now rare in most developed countries, Needle stick injuries in healthcare settings, Birth to an HCV-infected mother, HCV can also be spread infrequently through:
Sex with an HCV-infected person (an inefficient means of transmission),Sharing personal items contaminated with infectious blood, such as razors or toothbrushes (also inefficient vectors of transmission). Other healthcare procedures that involve invasive procedures, such as injections (usually recognized in the context of outbreaks)
Can HCV be spread during medical or dental procedures?
Yes, therefore Standard Precautions and other infection control practices should be followed routinely and consistently. There are However cases that HCV has been spread in healthcare settings when injection equipment, such as syringes, was shared between patients or when injectable medications or intravenous solutions were mishandled and became contaminated with blood. Healthcare personnel should understand and adhere to Standard Precautions, which includes safe injection practices and other guidance aimed at reducing blood borne pathogen risks for patients and healthcare personnel. If healthcare-associated HCV infection is suspected, this should be reported to state and local public health authorities.
Can HCV be spread within a household?
Yes, but does not occur very often. If HCV is spread within a household, it is most likely a result of direct, through-the-skin exposure to the blood of an infected household member.
Signs and symptoms of acute HCV infection:
Persons with newly acquired HCV infection usually are asymptomatic or have mild symptoms that are unlikely to prompt a visit to a healthcare professional. When symptoms occur, they can include; Fever, Fatigue, Dark urine, Clay-colored And approximately 20%–30% of those newly infected with HCV experience fatigue, abdominal pain, poor appetite, or jaundice. In those persons who do develop symptoms, the average time period from exposure to symptom onset is 4–12 weeks (range: 2–24 weeks).
Signs and symptoms of chronic HCV infection:
Most persons with chronic HCV infection are asymptomatic. However, many have chronic liver disease, which can range from mild to severe, including cirrhosis and liver cancer. Chronic liver disease in HCV-infected persons is usually insidious, progressing slowly without any signs or symptoms for several decades. In fact, HCV infection is often not recognized until asymptomatic persons are identified as HCV-positive when screened for blood donation or when elevated alanine aminotransferase (ALT, a liver enzyme) levels are detected during routine examinations.
Testing and Diagnosis HCV testing is recommended for anyone at increased risk for HCV infection, including:
Persons who have ever injected illegal drugs, including those who injected only once many years ago Recipients of clotting factor concentrates made before 1987, Recipients of blood transfusions or solid organ transplants before July 1992, Patients who have ever received long-term hemodialysis treatment.
Persons with known exposures to HCV, such as health care workers after needle sticks involving HCV-positive blood recipients of blood or organs from a donor who later tested HCV-positive
All persons with HIV infection. Patients with signs or symptoms of liver disease (e.g., abnormal liver enzyme tests), Children born to HCV-positive mothers (to avoid detecting maternal antibody, these children should not be tested before age 18 months)Several tests are performed for HCV infection,including; Screening tests for antibody to HCV (anti-HCV)enzyme immunoassay(EIA)enhanced chemiluminescence immunoassay (CIA)Recombinant immunoblot assay(RIBA)Qualitative tests to detect presence or absence of virus (HCV RNA polymerase chain reaction [PCR])Quantitative tests to detect amount (titer) of virus (HCV RNA PCR).
False-positive anti-HCV tests appear more often when persons at low risk for HCV infection (e.g., blood donors) are tested. Therefore, it is important to confirm a positive anti-HCV test with a supplemental test, such as RIBA (recombinant immunoblot assay), as most false positive anti-HCV tests are reported as negative on supplemental testing.
Persons with early HCV infection might not yet have developed antibody levels high enough that the test can measure which might result into a false negative. In addition, some persons might lack the (immune) response necessary for the test to work well. In these persons, further testing such as PCR for HCV RNA may be considered. A confirmed positive anti-HCV test is usually followed by other additional tests such as ALT (alanine aminotransferase, a liver enzyme). An elevated ALT indicates inflammation of the liver. The patient should be checked further for chronic liver disease and possible treatment. The evaluation should be performed by a medical doctor/ healthcare professional familiar with chronic hepatitis C. Also one can have a normal liver enzyme (e.g., ALT) level and still have chronic hepatitis C. It is common for patients with chronic hepatitis C to have liver enzyme levels that go up and down, with periodic returns to normal or near normal levels. Liver enzyme levels can remain normal for over a year despite chronic liver disease.
Management and Treatment:
HCV-positive persons should be evaluated (by referral or consultation, if appropriate) for presence of chronic liver disease, including assessment of liver function tests, evaluation for severity of liver disease and possible treatment, and determination of the need for hepatitis A and hepatitis B vaccination. A specialist can be consulted in the management of HCV-infected persons but, any physician who manages a person with hepatitis C should be knowledgeable and current on all aspects of the care of a person with hepatitis C; this can include some internal medicine and family practice physicians as well as specialists such as infectious disease physicians, gastroenterologists, or hepatologists.
Treatment for chronic hepatitis C:
Combination therapy with pegylated interferon and ribavirin is the treatment of choice, resulting in sustained virologic response (defined as undetectable HCV RNA in the patient's blood 24 weeks after the end of treatment) rates of 40%–80% (up to 50% for patients infected with genotype 1, and up to 80% for patients infected with genotypes 2 or 3). Combination therapy using interferon and ribavirin is approved for use in children ages 3–17 years in some countries. Treatment success rates are now being improved with the addition of polymerase and protease inhibitors to standard pegylated interferon/ribavirin combination therapy. At least six distinct HCV genotypes (genotypes 1–6) and more than 50 subtypes have been identified. It is necessary to do viral genotyping when managing a person with chronic hepatitis C. Because there are at least six known genotypes and more than 50 subtypes of HCV, genotype information is helpful in defining the epidemiology of hepatitis C and in making recommendations regarding treatment.
Knowing the genotype can help predict the likelihood of treatment response and, in many cases, determine the duration of treatment. Patients with genotypes 2 and 3 are almost three times more likely than patients with genotype 1 to respond to therapy with alpha interferon or the combination of alpha interferon and ribavirin. When using combination therapy, the recommended duration of treatment depends on the genotype. For patients with genotypes 2 and 3, a 24-week course of combination treatment is adequate, whereas for patients with genotype 1, a 48-week course is recommended. Once the genotype is identified, it need not be tested again; genotypes do not change during the course of infection. Super-infection is possible if risk behaviors (e.g., injection drug use) for HCV infection continue, but it is believed to be very uncommon.
Does chronic hepatitis C affect only the liver?
A small percentage of persons with chronic HCV infection develop medical conditions due to hepatitis C that are not limited to the liver. These conditions are thought to be attributable to the body's immune response to HCV infection. Such conditions can include;Diabetes mellitus, which occurs three times more frequently in HCV-infected persons, Glomerulonephritis, a type of kidney disease caused by inflammation of the kidney, Essential mixed cryoglobulinemia, a condition involving the presence of abnormal proteins in the blood, Porphyria cutanea tarda, an abnormality in heme production that causes skin fragility and blistering, Non-Hodgkins lymphoma, which might occur somewhat more frequently in HCV-infected persons, Counseling Patients.
Patients should be informed about the low but present risk for transmission with sex partners. Sharing personal items that might have blood on them, such as toothbrushes or razors, can pose a risk to others. Cuts and sores on the skin should be covered to keep from spreading infectious blood or secretions. Donating blood, organs,tissue, or semen can spread HCV to others. HCV is not spread by sneezing, hugging, holding hands, coughing, sharing eating utensils or drinking glasses, or through food or water. Patients may benefit from joining support group.
HCV-positive persons should be advised to avoid alcohol because it can accelerate cirrhosis and end-stage liver disease. Viral hepatitis patients should also check with a health professional before taking any new prescription pills, over-the counter drugs (such as non-aspirin pain relievers), or supplements, as these can potentially damage the liver.
Hepatitis C and Healthcare Personnel:
What is the risk for HCV infection from a needle stick exposure to HCV-contaminated blood?
After a needle stick or sharps exposure to HCV-positive blood, the risk of HCV infection is approximately 1.8% (range: 0%–10%).
Other than needle sticks, do other exposures, such as splashes to the eye, pose a risk to healthcare personnel for HCV transmission?
Although a few cases of HCV transmission via blood splash to the eye have been reported, the risk for such transmission is expected to be very low. Avoiding occupational exposure to blood is the primary way to prevent transmission of blood borne illnesses among healthcare personnel. All healthcare personnel should adhere to Standard Precautions. Depending on the medical procedure involved, Standard Precautions may include the appropriate use of personal protective equipment (e.g., gloves, masks, and protective eyewear).
What follow-up testing is recommended for healthcare personnel exposed to HCV-positive blood?
For the source, perform baseline testing for anti-HCV.For the person exposed to a HCV-positive source, perform baseline and follow-up testing, including baseline testing for anti-HCV and ALT activity and follow-up testing for anti-HCV (e.g., at 4–6 months) and ALT activity. If earlier diagnosis of HCV infection is desired, testing for HCV RNA may be performed at 4–6weeks. Confirmation by supplemental anti-HCV testing of all anti-HCV results reported as positive by enzyme immunoassay.
Pregnancy and HCV Infection:
Should pregnant women be routinely tested for anti-HCV?
No. Since pregnant women have no greater risk of being infected with HCV than non-pregnant women and interventions to prevent mother-to-child transmission are lacking, routine anti-HCV testing of pregnant women is not recommended. Pregnant women should be tested for anti-HCV only if they have risk factors for HCV.
What is the risk that an HCV-infected mother will spread HCV to her infant during birth?
Approximately 4 of every 100 infants born to HCV-infected mothers become infected with the virus. Transmission occurs at the time of birth, and no prophylaxis is available to prevent it. The risk is increased by the presence of maternal HCV viremia at delivery and also is 2–3 times greater if the woman is co-infected with HIV. Most infants infected with HCV at birth have no symptoms and do well during childhood. More research is needed to find out the long-term effects of Perinatal HCV infection.
Should a woman with HCV infection be advised against breastfeeding?
No. There is no evidence that breastfeeding spreads HCV. However, HCV-positive mothers should consider abstaining from breastfeeding if their nipples are cracked or bleeding.
When should children born to HCV-infected mothers be tested to see if they were infected at birth?
Children should be tested for anti-HCV no sooner than age 18 months because anti-HCV from the mother might last until this age. If diagnosis is desired before the child turns 18 months, testing for HCV RNA could be performed at or after the infant's first well-child visit at age 1–2 months. HCV RNA testing should then be repeated at a subsequent visit, independent of the initial HCV RNA test result.
Sunday, August 3, 2008
Hepatitis B virus (HBV) is a unique, coated DNA virus belonging to the Hepadnaviridae family of viruses, (partly double-stranded; icosahedral capsid with an envelope; virion-also called Dane particles as the main characteristics). It is not related to the hepatitis A virus or the hepatitis C virus. HBV primarily infect liver cells. The name of the family comes from hepa- meaning liver; dna- referring to deoxyribonucleic acid, the virus' genetic material; and viridae- meaning virus. Other viruses in this family can also cause hepatitis in certain animals e.g. mammalian and avian hepadnaviruses are known to exist. The Hepadnaviridae are very similar to one another. Accordingly, several animal models have been developed to study the hepatitis B virus and to evaluate new drugs to treat hepatitis B virus.The genes of the hepatitis B virus contain genetic codes to make a number of protein products, including hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), hepatitis B e antigen (HBeAg), and DNA polymerase.
These four proteins are important because their tests are used to diagnose hepatitis B virus. The hepatitis B virus consists simply of a core particle (central portion) and a surrounding envelope (outer coat). The core is made up of the HBcAg, whereas the envelope is made up of the HBsAg. The core particle contains the hepatitis B virus DNA, HBeAg, and DNA polymerase. The HBeAg serves as a marker of the virus' ability to spread the infection. The DNA polymerase is an important part of the virus' uniqueness of its reproduction. Of relevant importance here is that, the human immunodeficiency virus (HIV) also reproduces using this same process. As a result, many drugs that have been developed to inhibit this process of reproduction to treat HIV infection may also be effective in treating chronic hepatitis B viral infection.
HOW HBV CAUSES INJURY TO THE LIVER:
The hepatitis B virus itself does not directly cause damage to the liver. Rather, the body's immune (protective) response to the virus (a foreign material) paradoxically causes the damage. Thus, in a hepatitis B viral infection, the body's immune response to the virus is responsible for both the elimination of the hepatitis B virus from the body and recovery from the infection. Yet, at the same time, the injury to the liver cells is caused by that same immune response to the hepatitis B virus in the liver cells.
Therefore, there is a balance between the protective and destructive effects of the immune system's response to the hepatitis B virus. How this balance is achieved determines the outcome in an individual infected with hepatitis B virus. Therefore, an acute hepatitis B viral infection can lead to recovery (the usual outcome), to acute liver failure (rarely), and sometimes to chronic infection. The chronic infection can result in a healthy carrier state (in which the affected person harbors the virus but remains healthy) or progress to cirrhosis (severe scarring, or fibrosis, of the liver) and its complications, including liver cancer.
Hepatitis B virus is spread or acquired through exposure to infected blood or the body's secretions. The highest concentrations of hepatitis B virus are found in the blood, semen, vaginal discharge, breast milk, and saliva. There are only low concentrations of hepatitis B virus in the urine and none in the feces. Therefore, hepatitis B is not spread through food or water or by casual contact. Furthermore, hepatitis B virus is no longer or rarely transmitted by blood transfusions in most countries because all blood for transfusion is screened (tested) to exclude contamination with hepatitis B virus. In much of the developing world, (sub-Saharan Africa, most of Asia, and the Pacific), most people become infected with HBV during childhood, and 8% to 10% of people in the general population become chronically infected. In these regions liver cancer caused by HBV figures among the first three causes death by cancer in men.
High rates of chronic HBV infection are also found in the Amazon and the southern parts of Eastern and Central Europe. In the Middle East and Indian sub-continent, about 5% are chronically infected.
TRANSMISSION –IN SUMMARY:
Hepatitis B virus is transmitted by contact with blood or body fluids of an infected person in the same way as human immunodeficiency virus (HIV), the virus that causes AIDS. However, HBV is 50 to 100 times more infectious than HIV.
The main ways of getting infected with HBV are
Worldwide, most infections occur from infected mother to child, from child to child contact in household settings, and from reuse of non sterilized needles and syringes.
In many industrialized countries (e.g. Western Europe and North America, the pattern of transmission is different. In these countries, mother-to-infant and child-to-child transmission accounted for up to one third of chronic infections before childhood hepatitis B vaccination programmes were implemented.
Today however, the majority of infections in these countries are acquired during young adulthood by sexual activity, and injecting drug use. In addition, hepatitis B virus is the major infectious occupational hazard of health workers, and most health care workers have received hepatitis B vaccine. Hepatitis B virus is not spread by contaminated food or water, and cannot be spread casually in the workplace. High rates of chronic HBV infection are also found in the Amazon and the southern parts of Eastern and Central Europe. In the Middle East and Indian sub-continent, about 5% are chronically infected. In U.S., adolescents and young adults account for the majority of reported cases of hepatitis B infection. Sexual contact (intercourse) being the most common means of transmission. The virus also can be spread by hepatitis B virus-contaminated blood or body fluid in several different ways. These ways include intravenous drug use, skin-popping (injecting under the skin), tattooing, body piercing, and acupuncture using non-sterile instruments. Additionally, hepatitis B virus can be transmitted through the sharing of toothbrushes and razors. Finally, blood-sucking insects such as mosquitoes and bed bugs that are common in the tropics have reportedly spread hepatitis B virus.
Young children who become infected with HBV are the most likely to develop chronic infection. About 90% of infants infected during the first year of life and 30% to 50% of children infected between 1 to 4 years of age develop chronic infection. The risk of death from HBV-related liver cancer or cirrhosis is approximately 25% for persons who become chronically infected during childhood.
SYMPTOMS OF ACUTE HEPATITIS B:
Acute hepatitis B is the initial, rapid onset, short duration of illness that results from infection with hepatitis B virus. About 70% of adults with acute hepatitis B have few or no symptoms. The remaining 30% develop significant symptoms two to four months following exposure to the hepatitis B virus. This period of time between the exposure and the first symptoms is what is usually referred to as the incubation period. The most common symptoms of acute hepatitis B includes; fatigue, loss of appetite, nausea, and abdominal pain over the region of the liver. Jaundice (yellow skin) often accompanies these other symptoms. When this happens, the infection is commonly termed as acute icteric (jaundiced) hepatitis. Occasionally, individuals with acute hepatitis B develop the so-called prodromal symptoms. These are symptoms that start just the onset of the commonly showing symptoms. Sometimes, the prodromal symptoms resemble an allergic reaction, such as skin rash, pain and swelling of the joints, and low-grade fever. Other times, the prodromal symptoms resemble the symptoms of the flu. Rarely (in less than 0.5% of adults), individuals with acute hepatitis B can develop acute liver failure (fulminant hepatitis). These patients are extremely ill with the symptoms of acute hepatitis already described and the additional problems of confusion or coma (encephalopathy) and bruising or bleeding (coagulopathy). In fact, up to 80% of people with fulminant hepatitis can die within days to weeks.
DETERMINANT OF THE OUTCOME OF THE ACUTE HBV:
The individual's ability to eliminate (clear) the hepatitis B virus from the body and recover from acute hepatitis B depends on the strength of the body's immune response to the infection. The stronger the immune response, the greater is the likelihood of eliminating the virus and recovering. By the same token, however, the stronger the immune response, the more likely is the occurrence of acute liver injury and symptoms. On the other hand, a weaker immune response results in less liver injury and fewer symptoms. At the same time, however, the weaker immune response results in less viral elimination (clearance) and a greater likelihood of developing chronic hepatitis B viral infection. Indeed, most infants and children who acquire acute hepatitis B viral infection are asymptomatic, but their rate of developing chronic hepatitis B virus is greater than 95%. Most adults (about 95%), particularly those with acute, symptomatic, icteric hepatitis B (with jaundice), will recover completely from the infection within two to three months. They also will develop immunity, that is, protection from a subsequent hepatitis B viral infection. Moreover, these individuals rarely develop chronic liver disease. In contrast, those adults with few or no symptoms during their episode of acute hepatitis B, as compared to other adults with symptoms, are less likely to clear the infection and are more likely to develop chronic hepatitis B.
CHRONIC HEPATITIS B INFECTION:
The diagnosis of chronic hepatitis B can be made, by definition, only after six months from the onset of acute hepatitis B. It is often difficult to suspect the diagnosis of chronic hepatitis B based just on the patient's symptoms. The reason for this difficulty is that those individuals, who develop chronic hepatitis B, are usually the same individuals who had few or no symptoms to signal the onset of their acute hepatitis B.
Moreover, most individuals with chronic hepatitis B infection remain symptom free (asymptomatic) for many years, even up to two or three decades. During this time, the patient's liver blood tests usually are at most mildly abnormal and the inflammation and scarring (fibrosis) of the liver progresses little, if at all. Occasionally, however, these individuals with otherwise inactive chronic hepatitis B may develop flares (reactivation) of acute symptoms, elevated liver blood tests, and inflammation of the liver. These flares resemble acute hepatitis, but they can cause progression of the chronic liver scarring (fibrosis). They tend to occur in men who acquired the chronic infection at a young age.
At some point, however, the chronic hepatitis can progress to CIRRHOSIS (severe scarring, or fibrosis) of the liver. These patients then can develop the symptoms and signs (abnormal findings on physical examination) of cirrhosis. For example, they can become weak, fatigued, and susceptible to infections. They can also lose muscle mass, especially in the shoulders and upper legs. In fact, they can develop poor nutrition and weight loss from abnormal digestion, malabsorption, or abnormal liver metabolism of nutrients.
Thus, deficiencies can occur, for example, of vitamin A, which causes impaired vision at night, or of vitamin D, which causes thinning of the spine or hip bones (osteopenia). Patients with cirrhosis also often develop visible evidence (stigmata) of cirrhosis, including swollen breasts (gynecomastia), small (atrophic) testicles, red palms (palmar erythema), and characteristic dilated vessels on the skin (spider angioma).
ADVANCED LIVER CIRRHOSIS:
Ultimately, the progression of cirrhosis leads to what is commonly known as advanced cirrhosis, which is characterized by the development of certain complications. Advanced cirrhosis is sometimes referred to as cirrhosis or chronic liver failure. Some authorities also use the term, decompensated cirrhosis, as synonymous with advanced cirrhosis. Others, however, reserve the term, decompensated cirrhosis, for advanced cirrhosis that includes specifically any of the complications that result primarily from portal hypertension. (Some of the complications of advanced cirrhosis can have multiple causes.) This difference in terminology matters little because the important consideration in any particular case is to simply specify which of the complications of cirrhosis apply.
Accordingly, the complications of cirrhosis that indicate the presence of advanced cirrhosis are complications that include those resulting primarily from portal hypertension (fluid retention, encephalopathy, GI bleeding, hypersplenism, and the hepatorenal syndrome), as well as coagulopathy, jaundice, and the hepatopulmonary syndrome. Portal hypertension is the term for the increased pressure in the portal venous system that occurs in patients with advanced cirrhosis. (The portal venous system drains blood from the intestinal and abdominal organs to the liver.) The most common complications of cirrhosis that result primarily from portal hypertension are fluid retention, hepatic (liver) encephalopathy, and gastrointestinal (GI) bleeding. The retention of fluid leads to swollen ankles (edema) and a swollen abdomen( ascites).
Sometimes, the fluid in the abdomen becomes infected (spontaneous bacterial peritonitis), causing fever and abdominal pain. The hepatic encephalopathy causes drowsiness, confusion, and even coma. Widened (dilated) veins (varices) in the esophagus and stomach that burst can cause GI bleeding. As a result, the patient may vomit bright red blood or defecate dark (even tarry) blood. Some patients develop hypersplenism, a complication that is due, in part at least, to portal hypertension. These patients have an enlarged spleen (splenomegaly), decreased red blood cells (anemia), decreased white blood cells (leukopenia), and decreased platelets (thrombocytopenia). The anemia causes weakness; the leukopenia contributes to infections; and the thrombocytopenia impairs the clotting of blood. Patients with portal hypertension also can develop a serious problem with the functioning of their kidneys without actual damage to the kidneys themselves (hepatorenal syndrome).
In advanced cirrhosis also, other important complications can occur besides those due primarily to portal hypertension. For example, some patients are prone to easy bruising and bleeding, largely because the impaired function of the liver causes abnormalities in the blood clotting process (coagulopathy). Patients with advanced cirrhosis can also develop jaundice because the damaged liver is unable to adequately eliminate a yellow compound, called bilirubin. More rarely, some patients can develop difficulty with breathing because certain hormones released in advanced cirrhosis cause abnormal functioning of the lungs (hepatopulmonary syndrome).
LIVER CANCER (HEPATOCELLULAR CARCINOMA)-DUE TO ADVANCED CIRRHOSIS:
Finally, liver cancer can develop in chronic HBV infected patients as a complication of advanced cirrhosis. This primary (originating in the liver) cancer of the liver is most likely to occur in people with active hepatitis B virus reproduction. The way in which the cancer develops is not yet fully understood. It is thought, however, that the hepatitis B virus DNA somehow becomes incorporated into the liver cell DNA of the patient. The most common symptoms and signs of liver cancer are abdominal pain and swelling, an enlarged liver, weight loss, and fever. In addition, the liver tumors can produce and release a number of substances, including ones that cause increased red blood cells (erythrocytosis), low blood sugar (hypoglycemia), and high blood calcium (hypercalcemia). The most useful diagnostic screening tests for liver cancer are an alpha-fetoprotein blood test and an ultrasound imaging study of the liver.
HBV INVOLVEMENT OF ORGANS OUSTIDE THE LIVER-(EXTRA-HEPATIC):
Rarely, chronic hepatitis B infection can lead to disorders that affect organs other than the liver. The deposit of specific hepatitis B virus immune complexes in the various organs usually causes these disorders. A hepatitis B virus immune complex is the entity that results from the binding together of a hepatitis B virus antibody and a hepatitis B virus antigen. (An antigen is a substance that is foreign to the body and an antibody is a specialized protein that is produced by white blood cells in response to the antigen. Hepatitis B virus immune complexes that settle, or deposit, in the small arteries throughout the body can result in an inflammation of these vessels (vasculitis), called polyarteritis nodosa. This condition can cause a wide range of symptoms, including muscle weakness, nerve damage (neuropathy), deep skin ulcers, kidney problems with loss of protein in the urine, (proteinuria), and sometimes kidney failure, high blood pressure, unexplained fevers, and abdominal pain. The hepatitis B virus immune complexes can cause damage to the kidneys in yet another way. That is, the immune complexes can be deposited in the glomeruli(filtering elements) of the kidney, causing glomeronephritis, which is a different disease from polyarteritis nodosa.
DIAGNOSIS OF HBV:
Hepatitis B is diagnosed from the results of specific hepatitis B virus tests (serologies) that reflect the various components of the hepatitis B virus. These serological tests differ from the standard liver tests (such as the ALT and AST) that can become abnormal when the liver is damaged from whatever cause, including hepatitis B viral infection. HBsAg AND anti-HBs:
The diagnosis of hepatitis B infection is made primarily by detecting the hepatitis B surface antigen (HBsAg) in the blood. The presence of HBsAg means that there is active hepatitis B viral infection and the absence of HBsAg means that there is no active hepatitis B viral infection. Following an exposure to hepatitis B virus, HBsAg becomes detectable in the blood within four weeks. In individuals who recover from acute hepatitis B viral infections, the elimination, or clearance, of HBsAg occurs within four months after the onset of symptoms. Chronic hepatitis B viral infection is defined as the persistence of HBsAg for more than six months.
After the HBsAg is eliminated from the body, the antibodies to HBsAg (anti-HBs) usually appear. These anti-HBs provide immunity to subsequent hepatitis B viral infection. Likewise, individuals who are successfully vaccinated against hepatitis B virus have measurable anti-HBs in the blood.
The hepatitis B core antigen can only be found in the liver and cannot be detected in the blood. The presence of large amounts of hepatitis B core antigen in the liver indicates an ongoing reproduction of the virus. This means that the virus is active. The antibody to hepatitis B core antigen, known as the hepatitis B core antibody (anti-HBc), however, is detectable in the blood. As a matter of fact, two types of anti-HBc antibodies (IgM and IgG) are produced.
IgM anti-HBc is a marker (indicator) for acute hepatitis B infection. The IgM anti-HBc is found in the blood during the acute infection and lasts for up to six months after the onset of symptoms. IgG anti-HBc develops during the course of the acute hepatitis B viral infection and persists for life, regardless of whether the individual recovers or develops the chronic infection. Accordingly, only the IgM type of anti-HBc can be specifically used to diagnose an acute hepatitis B viral infection. Moreover, determining just the total anti-HBc (without separating its two components) is not very helpful.
HBeAg, anti-HBe, AND PRE-CORE MUTATIONS:
Hepatitis B e antigen (HBeAg) and its antibody, anti-HBe, are useful markers to determine the likelihood of spread of the virus (transmissibility) by persons affected with chronic hepatitis B viral infection. Detecting both HBeAg and anti-HBe in the blood is usually mutually exclusive. Accordingly, the presence of HBeAg means ongoing viral activity and the ability to infect others, whereas the presence of anti-HBe signifies a more inactive state of the virus and less risk of transmission.
In some individuals infected with hepatitis B virus, the genetic material for the virus has undergone a particular structural change, called a pre-core mutation. This mutation results in an inability of the hepatitis B virus to produce HBeAg, even though the virus is actively reproducing. This means that even though no HBeAg is detected in the blood of people with the mutation, the hepatitis B virus is still active in these persons and they can infect others.
Hepatitis B virus DNA:
The most specific marker of hepatitis B virus reproduction is the measurement of hepatitis B virus DNA in the blood. You remember that DNA is the genetic material of hepatitis B virus. High levels of hepatitis B virus DNA indicate an ongoing reproduction of the virus and viral activity. Low or undetectable levels of hepatitis B virus DNA are associated with the inactive phase of hepatitis B viral infection. Several different laboratory tests (assays) are available to measure hepatitis B virus DNA.
The PCR- (polymerase chain reaction) is the most sensitive method (assay) for determining the level of hepatitis B virus DNA. This means that the PCR is the best method for detecting minute amounts of the hepatitis B virus marker. This method works by amplifying the material that is being measured up to a billion times for its detection. The PCR method, therefore, can measure as few as 50 to 100 copies (particles) of hepatitis B virus per milliliter of blood. This test, however, is actually too sensitive for practical diagnostic use.
The purpose of measuring hepatitis B virus DNA usually is to determine whether the hepatitis B viral infection is active or inactive (quiescent). This distinction can be made based on the amount of hepatitis B virus DNA in the blood. High levels of DNA indicate an active infection, while low levels indicate a dormant, or inactive, infection. Thus, patients with dormant disease have about a million viral particles per milliliter of blood, whereas patients with active disease have several billion particles per milliliter. Therefore, anyone who is HBsAg positive, even if the hepatitis B viral infection is inactive, will have detectable levels of hepatitis B virus DNA by the PCR method because it is so sensitive.
For practical purposes, hepatitis B virus DNA can be measured using a so-called hybridization method (assay), which is a less sensitive test than the PCR. Unlike the PCR method, the hybridization assay measures the viral material without amplification. Thus this test can detect hepatitis B virus DNA only when many viral particles are present in the blood, meaning that the infection is active. In other words, from a practical point of view, if hepatitis B virus DNA is detected with a hybridization assay, this means that the hepatitis B viral infection is active.
PREVENTION AND TREATMENT:
Liver cancer is almost always fatal, and usually develops between 35 and 65 years of age, when people are maximally productive and with family responsibilities. The loss of a mother or a father can be devastating to the entire family. In developing countries, most people with liver cancer die within months of diagnosis. In industrialized countries, surgery and chemotherapy can prolong life up to a few years. Chronic hepatitis B in some patients can be treated with drugs such as interferon or lamivudine, which can help some patients. However, interferon or lamivudine therapies are very costly and therefore few individuals can afford them and will never be available to most patients in developing countries due to their costs. Patients with cirrhosis are sometimes given liver transplants, with varying success. It is preferable to prevent this disease with vaccine than to try to cure it.
SAFETY AND EFFECTIVENESS OF THE HBV CACCINES:
The vaccine is given as a series of three intramuscular doses. It has been said that the vaccine is 95% effective in preventing children and adults from developing chronic infection if they have not yet been infected. In many countries where 8% to 15% of children used to become chronically infected with HBV, the rate of chronic infection has been reduced to less than 1% in immunized groups of children. And the reports are showing that. Since 1982, over one billion doses of hepatitis B vaccine have been used worldwide.
All countries have been urged by world bodies to add hepatitis B vaccine into their national immunization programmes. As of March 2000, 116 countries had included hepatitis B vaccine in their national programmes including most countries in Eastern and South- East Asia, the Pacific Islands Australia, North and South America,Western Europe and the Middle East. However, many low income countries in sub-Saharan Africa, the Indian subcontinent and in the Newly Independent States do not use the vaccine. The price of the hepatitis B vaccine has been one of the main obstacles to its introduction in many of these countries.
The Global Alliance for Vaccines and Immunization (GAVI) was created in 1999. It is a unique coalition of public and private institutions. The main mission of GAVI is to vaccinate as many children as possible against vaccine-preventable diseases. GAVI has introduced a new approach to international health funding: the Global Fund for Children's vaccines (GFCV). This fund will help 74 low-income countries including those in the sub-Saharan Africa, Asia and Southern America to reinforce their national vaccine programmes and introduce hepatitis B, yellow fever and haemophilus influenzae type b (Hib) vaccines into their national immunization programmes.