U.S. researchers say even if an HIV vaccine doesn't offer perfect protection against the virus, it might provide a survival advantage after infection.
Such a survival advantage was observed in two monkey studies sponsored by the National Institute of Allergy and Infectious Diseases.
One team of researchers was led by Dr. Norman Letvin of Beth Israel Deaconess Medical Center, Harvard Medical School and the NIAID Vaccine Research Center, while the other team was led by Mario Roederer of the VRC.
Both teams found monkeys vaccinated against simian immunodeficiency virus -- a close relative of HIV that causes an AIDS-like disease in monkeys -- and then exposed to the virus survived significantly longer than unvaccinated animals exposed to SIV.
The studies also identified a measurable marker of SIV vaccine effectiveness in monkeys -- something known as an immune correlate of vaccine efficacy. But the researchers say further study is needed to determine if the immune correlate could predict the effectiveness of a vaccine against HIV in humans.
The research appears in this week's issue of Science and this month's issue of the Journal of Experimental Medicine.
Copyright 2006 by United Press International
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