HIV isolated from newly infected people tends to have certain genetic variations that help it to thrive in its new host.
When HIV-1 spreads from one heterosexual partner to another, a single viral variant typically takes hold. To determine if these successful viruses share any traits, a team led by Jonathan Carlson at Microsoft Research in Redmond, Washington, and Eric Hunter at Emory University in Atlanta, Georgia, analysed viral genetic diversity in 137 heterosexual pairs shortly after HIV transmission from one partner to the other.
The viruses that established infection tended to have the same genetic mutations that boost fitness — for instance by improving the stability of the virus's proteins.
Drugs or vaccines that drive the selection of even slightly less fit HIV variants could prevent new infections, even when the virus is transmitted, the researchers say.
Science http://doi.org/tpc (2014)