The immediate use of antiretroviral drugs to prevent HIV sero conversion after exposure to potentially HIV-infected blood or body fluids is called Post-exposure prophylaxis for HIV infection (HIV-PEP).
The efficacy of HIV-PEP has been shown in occupational settings but the evidence is indirect. Studies suggest that when initiated within 12, 24, or 36 hours after exposure HIV-PEP is more effective than initiation within 48 to 72 hours, and that HIV-PEP is not effective when given more than 72 hours following the exposure. Furthermore, a 28-day course of drug therapy appears to be more effective than courses lasting 3 or 10 days.
Since HIV-PEP is not 100% effective, the importance of primary prevention must be reinforced (see sections on healthcare-associated infections, health sector, and workplace).
The use of HIV-PEP following possible occupational exposure in settings such as hospitals has become a routine component of occupational safety policy in most of North America and Europe.
Non-occupational use of HIV-PEP has been introduced and is being studied in settings supporting sexual assault survivors, rape survivors in refugee camps, and persons in communities at high risk of HIV, such as sex workers, people who use injection drugs, men who have sex with men, and people in prisons. Risk behaviour has not been shown to increase substantially among HIV-PEP users and in communities where HIV-PEP is available.
A key consensus at the 2005 Joint International Labour Organization/World Health Organization Technical Meeting for the Development of Policy and Guidelines regarding occupational and non-occupational HIV-PEP was that HIV-PEP must be part of comprehensive HIV prevention, occupational health, and post-rape care service policies. Services must be provided as part of a comprehensive prevention package that emphasizes primary prevention.