Rapid Evolution of HIV May Slow its Ability to Cause AIDS

It turns out that the rapid evolution of HIV may actually be slowing its ability to cause AIDS. Scientists have discovered that the same ability that has allowed the virus to develop resistance to patients' natural immunity is also hindering its spread.

In 2013, there were a total of 35 million people living with HIV worldwide. Needless to say, this makes the ability to control the HIV epidemic paramount. That's why researchers have continually explored the ways in which HIV has evolved over time.

In this latest study, the scientists conducted their research in Botswana and South Africa, two countries that have been worst affected by the HIV epidemic.  The scientists then examined 2,000 women with chronic HIV, looking at whether the interaction between the body's natural immune response and HIV leads the virus to becoming less virulent.

Central to the study were the proteins in blood called the human leukocyte antigens (HLA). These enable the immune system to differentiate between the human body's proteins and proteins of pathogens. People with a gene that expresses a particular HLA protein called HLA-B*57 are known to benefit from a protective effect to HIV; infected patients with this gene progress more slowly than usual to aids.

In this case, the researchers found that viral adaptation to protective gene variants, such as HLA-B*57, is driving down the virulence of transmitted HIV. This, in turn, is contributing to HIV elimination. Not only that, but a mathematical model revealed that selective treatment of people with low CD4 counts will accelerate the evolution of HIV variants with a weaker ability to replicate.

"This research highlights the fact that HIV adaptation to the most effective immune responses we can make against it comes at a significant cost to its ability to replicate," said Phillip Boulder, one of the researchers, in a news release. "Anything we can do to increase the pressure on HIV in this way may allow scientists to reduce the destructive power of HIV over time."

The findings are published in the journal Proceedings of the National Academy of Sciences.

For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).