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HIV Aids

Human immunodeficiency virus known as HIV, also known as HTLV-III and lymphadenopathy-associated virus) is a retrovirus that is the cause of the disease known as AIDS (Acquired Immunodeficiency Syndrome), a syndrome where the immune system begins to fail, leading to many life-threatening infections.

HIV primarily infects vital areas of the human immune system such as CD4+ T cells, macrophages and dendritic cells.

It also destroys CD4+ T cells. As CD4+ T cells are required for the proper functioning of the immune system, when enough CD4+ T cells have been destroyed by HIV, the immune system functions poorly, leading to AIDS.

HIV also directly attacks vital organs such as the kidneys, heart and brain, leading to acute renal failure, cardiomyopathy, dementia and encephalopathy.

Most of the problems faced by people infected with HIV result from failure of the immune system to protect from opportunistic infections and cancers.

HIV is transmitted through direct contact of a mucous membrane with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid or breast milk.

This transmission can come in the form of: penetrative (anal or vaginal) sex; oral sex; blood transfusion; contaminated needles; exchange between mother and infant during pregnancy, childbirth, or breastfeeding; or other exposure to one of the above bodily fluids.

As of the end of 2005, the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organization (WHO) estimated that AIDS has killed more than 25 million people since it was first recognized on December 1, 1981.

In 2005 alone, AIDS claimed an estimated 2.5 - 3.5 million lives.

A third of these deaths are occurring in sub-Saharan Africa. Current estimates state that HIV is set to infect 90 million people in the continent.

Antiretroviral treatment reduces both the mortality and the morbidity of HIV infection, but routine access to antiretroviral medication is not available in all countries especially poor ones where the resources are simply not devoted in terms of both education, prevention and cure.

HIV infection is a disease that can be treated, but as yet there is no cure.

There are however effective means of preventing complications and delaying progression to AIDS.

At the present time, not all people infected with HIV have progressed to get AIDS, but it is generally believed that the vast majority will.

A combination of several antiretroviral agents, termed Highly Active Anti-Retroviral Therapy HAART, have been effective in reducing the number of HIV particles in the blood stream (as measured by a blood test called the viral load).

This can improve T-cell counts. This is not a cure for HIV, and people on HAART with suppressed levels of HIV can still transmit the virus.

There is good evidence that if the levels of HIV remain suppressed and the CD4 count remains greater than 200, then the quality and length of life can be significantly improved and lengthend.

Improved antiretroviral inhibitors against proteins such as Reverse transcriptase, Integrase and Tat are being researched and developed. One of the most promising new therapies is a new class of drugs called fusion or entry inhibitors.

Current recommendations for treatment include at least a three drug effective regime to induce complete cease of viral replication and reduce the incidence of new mutations.

Current drug classes include NNRTI, NRTI, NtRTI, PI, FI.

Each of the drugs in these classes represent individual pharmacodynamics and toxicities, requiring expert knowledge to appropriately select and dose an effective combination.

On July 12, 2006, The Food and Drug Administration approved the first once-daily pill for fighting AIDS, according to the drug's makers, Bristol-Myers Squibb and Gilead Sciences. Atripla, a combination of three widely used anti-retroviral drugs, was fast-tracked by the FDA and will be made available for purchase in many other countries.

Post-exposure prophylaxis (PEP) with a course of antiviral drugs is also thought to reduce the risk of seroconversion after high risk exposure (unprotected anal or vaginal sex) to HIV.

To be effective, it must be started as soon as possible after exposure and no later than 72 hours post-exposure.

The treatment for HIV lasts four weeks. While there is data to suggest that PEP after HIV exposure is extremely effective, it has not been effective in all cases

As yet, no vaccine has been developed to prevent HIV infection or disease in people who are not yet infected with HIV.
Researchers worldwide are seeking to produce a vaccine, through the International AIDS Vaccine Initiative.

Despite the vast resources devoted there is as yet no known cure but vast strides have been made in recent years in terms of treatment and a cure looks a distinct possibility in the near future.