Kenyans could, before the end of this year, have access to a drug that protects them from HIV infection in what is seen as a major breakthrough in the fight against Aids.
About 1,000 commercial sex workers are already using the newly-approved HIV/Aids combination therapy drug Truvada (emtricitabine and tenofovir), ahead of its rollout later this year.
Known as pre-exposure prophylaxis (PrEP) and used as an antiretroviral drug, Truvada works by inhibiting the key enzyme, reverse transcriptase, which the HIV virus needs to infect host cells, and effectively blocks infection.
Pre-exposure prophylaxis means the drug is taken before exposure to risk of infection. Once taken, the drug is effective for eight hours.
Kenya approved the drug last year, becoming the second country in Africa, after South Africa, to allow its use.
Three organisations are conducting demonstration trials on the drug for one year in Nairobi, Kisumu and Homa Bay.
The Sex Worker Outreach Programme (SWOP) provides male and female sex workers with daily doses of Truvada in Nairobi and Kisumu.
Liverpool VCT Care and Treatment is conducting its demonstration trials in Nairobi, Kisumu and Homa Bay, and Centre for Disease Control and Prevention is conducting trials in Homa Bay.