HIV post-exposure prophylaxis (PEP): eligibility of sexually infected patients diagnosed at the time of primary infection

Question: Post-exposure prophylaxis (PEP) is effective in preventing HIV in fection after professional exposure. PEP is also recommended after inadvert ent sexual exposure if two conditions are met: the source person is known t o be HIV infected, and exposure to this person occurred only once or is acc idental. The objective of this study is to describe the circumstances of se xual exposure and determine how frequently these conditions were present am ong patients diagnosed during primary HIV infection. Methods: Physicians of 35 patients diagnosed with primary HIV infection pro vided detailed information on the circumstances of infection as well as on the patients and source persons. Results: Most patients were homosexual (71%), and 91% were male. Only one p atient (3%) had a single exposure with a known HIV-infected person and was therefore eligible for PEP Eight patients (23%) who did not know the HIV st atus of their partner would have been eligible considering single exposure as a sufficient criterion for PEP. Ore-genital contact appears to account f or transmission in four instances. Eleven persons (31%) were infected after sexual contact with their stable partner, of whom 7 did not known his/her HIV status. Twelve patients (34%) were infected after multiple unprotected sexual contact with unknown partners. Conclusion: The direct impact of PEP in terms of HIV infections prevented i s likely to be small. PEP will not make up for the failure of other prevent ion methods. It may, however, contribute to the disclosure and the discussi on of risk situations and help physicians provide individual counselling ta king into account the precise context of risk behaviour.