The challenges of preexposure prophylaxis for bacterial sexually transmitted infections.

Preexposure prophylaxis (PrEP) against HIV is currently the subject of great interest, as clinical trials have shown high efficacy in terms of decreasing transmission among men who have sex with men. Because the prevalence of bacterial sexual transmitted infections (STIs) is increasing within this community, a recent pilot study demonstrated the efficacy of reducing transmission of bacterial STIs by administering PrEP with daily doxycycline to men who have sex with men. This creative initiative raises several questions which are discussed in this review. Relevant information should be drawn from the huge amount of available epidemiologic data to identify those who could benefit from such prophylactic treatment. The choice of antimicrobial agents is crucial, as antimicrobial susceptibility of STI agents is heterogeneous. Finally, we discuss challenges to improve the control of STIs through the use of PrEP.