JOHANNESBURG – About 5 000 women in four southern African countries will soon participate in an Aids prevention trial to establish whether some antiretrovirals (ARV) used to treat HIV can also be used to prevent the disease when administered both as microbicide gel or oral tablets.

"We think its very unique because nobody has really tested the difference between an oral route of prevention compared to a vaginal route of prevention," Dr Mike Chirenje, protocol co-chair for the study, told international media on the sidelines of an AIDS conference in Cape Town on Wednesday.

A microbicide is a gel or cream women and even men can use to protect themselves against the AIDS virus if their partners cannot or are unwilling to use condoms.

The study – to be conducted by the US-funded Microbicide Trials Network – will focus on sexually active women from Zimbabwe, South Africa, Zambia, Malawi and Uganda in central-eastern Africa.

The research will specifically test the ARV tablets – Tenofovir and Truvada – as well as establish which of the two approaches women would prefer.

Tenofovir is also the active ingredient in the vaginal gel.

"Its not so much which was best, in so much as what would women prefer," Chirenje said.

The study which seeks to reduce the disease burden among women is expected to last three and a half years before first results in 2012.

Recent studies have shown that microbicides can protect women – who represent nearly 60 percent of adults living with HIV in the world's worst affected sub-Saharan Africa region – from catching the virus.—

By Staff reporter and agencies