Antiretroviral treatment lowers rates of HIV transmission in heterosexual couples in Africa
Antiretroviral treatment is associated with a lower risk of heterosexual HIV transmission in African serodiscordant couples, according to findings from Uganda, Rwanda and Zambia, presented on Monday at the Sixteenth Conference on Retroviruses and Opportunistic Infections.
HIV sporadically detectable in semen of men with undetectable plasma viral loads
At the Sixteenth Conference on Retroviruses and Opportunistic Infections in Montreal on Monday morning, two back-to-back oral presentations affirmed that HIV is indeed often detectable in semen despite undetectable viral loads in blood plasma. The two studies found measurable HIV RNA ("viral shedding") in 3% to 14% of seminal fluid samples taken from study participants with undetectable plasma viral loads.
Seminal HIV: cell-free virus, not infected cells, leads to transmission between men
At the Sixteenth Conference on Retroviruses and Opportunistic Infections in Montreal on Monday morning, David Butler of the University of California San Diego presented data on four cases of male-to-male sexual transmission, showing that cell-free virus in semen – not proviral DNA in infected cells – was the means of transmission in all four cases.
PrEP could work even if taken several days in advance
A study using tenofovir and FTC (Truvada) to prevent rectal SHIV infection in monkeys – so-called pre-exposure prophylaxis (PrEP) - has shown that it is as effective for the medication to be given up to three days before exposure as it is one day before. Even giving Truvada a full week before exposure resulted in a considerable reduction in the risk of infection.
Microbicide reduces HIV infections by 30% in first success for field
Campaigners were celebrating the results of a trial of a microbicide to prevent HIV that has produced a positive result, the first one to do so. The results of the HPTN 035 were announced at the Sixteenth Conference on Retroviruses and Opportunistic Infections in Montreal today.
High-dose tenofovir microbicide completely protects monkeys
An animal study has found that a single dose of a microbicide gel containing tenofovir and FTC completely protected six out of six monkeys given a twice-weekly vaginal challenge of a combined human/monkey virus called SHIV. No monkeys were infected after 20 challenges with the virus whereas monkeys no given the microbicide were infected after an average of four challenges.