The relatively high efficacy of post-exposure prophylaxis (PP) with antiretroviral drugs for occupational HIV infection has led to consider the possibility and effectiveness of its implementation in lay contact associated with the risk of infection with this infection. However, significant differences between occupational and non-occupational infections do not allow extrapolating data on the efficacy of PP in people who have been exposed to occupational exposure to a potential source of infection in situations where the exposure was unprofessional.

The aim of the study by M.E. Roland et al. (USA), was the determination of the frequency and causes of the occurrence of seroconversion after PP in people exposed to unprofessional contact with a potential source of HIV infection.

Previously uninfected people who reported an episode of sexual contact or intravenous drug use in which HIV infection could occur, lasting up to 72 hours, received 28 days of antiretroviral therapy. The concentration of anti-HIV antibodies was determined 12 weeks after the start of post-exposure prophylaxis.

Of the 877 people included in the study, only 702 continued to participate at 12 weeks. Seroconversion occurred in 7 of 702 participants (1%; 95% confidence interval 0.4% -2%), when they were all men and had homosexual contact. From the time of potential infection to the start of post-exposure prophylaxis, they spent an average of 45.5 hours, while the rest of the study participants - 32.5 hours. the ineffectiveness of prevention. The other 4 participants with seroconversion after the start of PP had additional contact with potential sources of HIV infection, which made it difficult to determine the causes of seroconversion. Information on the sources of infection in the 7 individuals was not available, so it was not possible to determine the genetic agreement of the viruses with that of the potential sources of infection.

Post-exposure prophylaxis in people who have had unprofessional contact with a potential source of HIV infection is not 100% effective, researchers say, and the frequent lack of information on the source of infection, as well as continuous contact with it, does not allow us to reliably determine its effectiveness. All of the above highlights the importance of primary HIV prevention.