Belgian
researchers say HIV has become weaker

Researchers in Belgium report that HIV may have become weaker since the late 1980s and may spread less rapidly in the body than the virus did 15 years ago, AIDSmap.com reports. Studying HIV-1 isolates taken from treatment-naive patients in both 1986-1989 and in 2002-2003, the researchers report that HIV appears to have become less virulent--HIV from the 1980s was able to infect immune system cells and kill them much more effectively than virus collected from HIV patients today.

The researchers, writing in the October 15 edition of the journal AIDS, report that the HIV viral fitness from the most recent samples had a mean replicative fitness of just 55% of that from samples from the 1980s. Viral fitness is a measurement of how easily and how quickly HIV is able to infect human cells and begin making copies of itself. The scientists theorize that the virus may slowly lose its ability to easily and quickly replicate as it mutates to develop stronger defenses against immune system attacks against it.

The researchers say their findings are the first to suggest that HIV may weaken over time. If the data holds true and HIV continues to weaken, it could evolve within the next 50 to 60 years to a point where it no longer causes deaths in humans, the researchers theorize.

But some scientists warn that even though HIV may be weakening, it still remains contagious and deadly. Marco Vitoria, an AIDS expert at the World Health Organization, also points out that other diseases, like tuberculosis and syphilis, have weakened over thousands of years but still remain deadly, Bloomberg News reports. "Attenuation isn't new in the natural history of many other infectious diseases and is a very slow process, to be measured not in years but in generations," he told the news service. (Advocate.com)