When People Don't Know

Based on their clustered, limited viral mutations, 49% of people studied during their early HIV infection phase contracted HIV from someone who was similarly in the early infection stage, according to a report by Canadian researchers in the April 1 edition of The Journal of Infectious Diseases. Because the early infection stage can be entirely asymptomatic, says study leader Mark Wainberg of the McGill AIDS Center, newly infected people probably don't know that they are and will often test negative by conventional antibody screening. Because newly infected individuals have higher viral loads'but usually don't yet have many detectable antibodies to the virus'they have a higher risk of transmitting the virus to others. 'We must do a much better job of identifying recently infected people,' Wainberg says, 'if we are to be able to counsel them to modify high-risk sexual behavior and desist from transmitting the virus.'