A sign encourages people in Simonga, Zambia, to get tested for HIV. Photo by Jon Rawlinson, used under Creative Commons licensing.Reposted from the Evolution in a Toxic World blog with permission In case you missed it, there’s some positive news on the rapid evolution front. We all know that HIV the virus that causes AIDS is a master of evolution. Rapidly evolving in response to both drugs and the human immune response. Yet after battling it out over several decades at the cost of too many human lives, it looks like human immunity may finally be pushing the virus in a more favorable direction—reduced virulence (or, capacity to cause disease.) While a study back in 2007 asked hopefully whether the HIV virus may be evolving towards reduced virulence the conclusion was that although it may be possible, “With the exceptions of anecdotes, a few case reports and one published study on a large cohort, there is no evidence that HIV-1 virulence has either increased or decreased during the past 20–30 years of the pandemic.” Now there is more than anecdote. A new study by a group of scientists from around the globe concludes that at least in one population (HIV infected women in Bostwana) “people infected with HIV are likely to progress to AIDs more slowly.” Apparently the cost of evolving to evade our our immunity, may be paid by the viruses ability to replicate. In this case rapid evolution, has tipped the balance in our favor and perhaps opened the door for scientists to consider using the evolutionary process to our advantage. Here is a quote from the lead scientist, as published in a University of Oxford press release,
‘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 lead scientist Professor Phillip Goulder from the University of Oxford. ‘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.’This doesn’t mean the HIV problem is solved of course or that we can sit back and let evolution take its course…just that there’s hope.