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span class="inline inline-left">Protection: A youth center in Johannesburg, South Africa, is partnering with the local Department of Health to help raise awareness about HIV/AIDS in the area. Reuters/Siphiwe SibekoEverybody knows that a recently acquired HIV infection will not lead to an immediate breakdown in the immune system.

Usually this will happen slowly and will take several years before leading to full-blown AIDS, with its dreadful clinical features. If not immediately taken care of professionally, the disease will likely lead to death.

Most HIV-infected persons will develop AIDS after 4 years, however for a small number, this waiting period is less than 4 years (known as Rapid Progressors). In extreme cases, it may even be less than a year.

But, there are a very few lucky ones, the so-called Long Term Non-Progressors (LTNP), in whom HIV infection will not progress to AIDS.

They will remain symptom free for many years (at least 8 years, sometimes even reaching 12 to 15) despite not being treated with anti-retroviral drugs.

Their CD-4 T Lymphocytes also do not decline progressively and will stay at a safe level, i.e. above 500 cells/ul.

In contrast to the usual course of the disease, where the viral load in the patient’s blood increases progressively with time, amazingly in LTNP it remains low all the time, and in some individuals remains undetectable in follow-up periods. As the risk of infecting others is proportional to the viral load, in LTNP it is very low.

Another parameter for HIV is HIV DNA in peripheral blood mononuclear cells. LTNP have lower amounts as compared with “normal” progressors, and is even undetectable in some.

However, we should take into account that the term LTNP does not denote a homogenous group.

This group comprises those infected with HIV that does not replicate efficiently, next to the “true” non-progressors in whom HIV shows normal virulence and replication properties.

It is also known that HIV subtype A is associated with a slower progression towards AIDS as compared with other subtypes.

In LTNP, soon after an HIV infection, the immune system already begins to show its protective properties. It turns out that a high percentage of LTNP carry the HLA B57 gene, which in the case of HIV infection will produce more potent killer T Cells that can better and quicker kill HIV, but unfortunately they might also attack the body’s own cells, leading to auto-immune diseases.

HIV uses the CCR-5 gene to gain entry into CD4 T lymphocytes. If, somehow, there is a mutation then it might confer some immunity against further HIV progression.

It has been shown that this is the case with LTNP as compared with AIDS patients in general and rapid-progressors in particular.

The age of the individual being infected for the first time with HIV also plays a crucial role. For those at age 40 or more, the progression will usually be rapid. On the other hand, most LTNP were infected in their early 20s.

Only the course of the disease can make an absolute distinction between these two subgroups as there are patients who develop AIDS many years after a stable infection. There are reports that it might even reach 15 years in some cases.

Also, for still obscure reasons, a significant number of LTNP (up to slightly above 50 percent) after + 10 years will lose their non-progressor status and develop AIDS. This reversal adds to the list of unsolved mysteries related to LTNP.

Nevertheless, a lot of research has already been done to investigate the protective mechanisms involved with the hope that they can be mimicked in anti-HIV vaccines and medicines.

Hopefully within the not too distant future, significant breakthroughs will happen for the benefit of mankind in general, especially those already infected with this formidable foe, the Human Immunodeficiency Virus.

It should never be forgotten that the number of LTNP is very small, not even reaching 1 percent of HIV-positive people, and during the course of time will dwindle.

There is no data on HIV LTNP in Indonesia so far