One in 10 newly diagnosed HIV-positive people have at least one "significant mutation" of the virus "associated with drug resistance," Mark Wainberg, director of the McGill AIDS Centre at the Jewish General Hospital in Montreal, Canada, said on Tuesday at the Microbicides 2006 Conference in Cape Town, South Africa, the SAPA/Mail & Guardian reports (SAPA/Mail & Guardian, 4/25). The conference, which is being attended by more than 1,000 scientists, aims to review progress in producing microbicides, which have been in development for 15 years. Microbicides include a range of products -- such as gels, films and sponges -- that could help prevent the sexual transmission of HIV and other infections (Kaiser Daily HIV/AIDS Report, 4/24). "HIV can mutate at every possible basis, daily," Wainberg told the conference on Tuesday, adding, "To be useful, a microbicide should be effective against all circulating HIV strains." According to Wainberg, HIV subtype C, which is more prevalent in China, India and Southern Africa, is more likely than subtype B, found mainly in North America and Europe, to develop a mutation that is resistant to some antiretroviral drugs, such as tenofovir. He also said that antiretroviral resistance might "develop because of microbicides," adding, "The virus will always do what is easiest for the virus" (SAPA/Mail & Guardian, 4/25).