- Blood will be collected for HIV testing for HIV negative participants, syphilis and storage. Participants will be followed up for three years with one six-monthly visits in the first year and then annually. A 6th study visit to discuss all study results will take place 2-3 months after the 5th study visit. A behavioural questionnaire, blood collection (except at six month); an anal swab and HRA will be administered at all follow up interviews.