Although Switzerland's Federal AIDS Commission said January 30 that HIV-positive people who are on an antiretroviral regimen cannot pass the virus to a negative partner, health officials and AIDS advocates worry that these new findings are misleading, Agence France-Presse/Yahoo News Reports (news.yahoo.com, 1/30).

According to critics, the claim made by Swiss officials—based on four separate studies—is focused on sex among heterosexuals. One study in Spain followed 393 heterosexual serodiscordant couples from 1990 to 2003 and found that none of the negative participants were infected if their partner was taking antiretrovirals. No similar studies have examined serodiscordant homosexual couples.

“We don’t feel the scientific evidence is conclusive, and there are some key issues that are not covered in this advice,” says Roger Peabody of the Terrence Higgins Trust AIDS charity in London.

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