The Mambo Matatu study wants to test two different interventions to improve sexually transmitted infection (STI) control among young gay, bisexual, and other men who have sex with men (GBMSM) in Kenya.

Participants attend quarterly study visits over 18 months to help determine which of the two interventions we are testing does a better job of controlling STI among GBMSM, compared to standard of care. 

 
1. One intervention that may reduce STIs among GBMSM is periodic presumptive treatment (PPT),in which participants are treated every 3 months for STI regardless of symptoms. STI PPT has been recommended by the World Health Organization for GBMSM but never tested in a randomized trial.  
2. The other intervention is called doxyPEP, which consists of taking a medication called
doxycycline 24-72 hours after condom less sex, as post-exposure prophylaxis (PEP) to prevent STI. DoxyPEP has been found to reduce STI among GBMSM in the United States and France but has not been tested among GBMSM in sub-Saharan Africa.  
3 No one knows if STI PPT or DoxyPEP is better at reducing STI among GBMSM in Kenya and similar settings.  

About 2900 people will take part in this study. 985 in Kisumu, Anza Mapema clinic, 985 in Mombasa Ganjoni Clinic and 985 in Nairobi SWOP clinic.