Programmatic mapping to determine the size and dynamics of sex work and injecting drug use in Mauritius.

HIV in Mauritius is in a concentrated phase. Most HIV infection is among key populations (KPs) including female sex workers (FSW), people who inject drugs (PWID), men who have sex with men (MSM), and transgender sex workers (TGSW). The objective of this research was to use geographical mapping to determine the precise locations, typologies and population estimates of each KP in Mauritius. From May to July 2014 a programmatic mapping approach determined national estimates and information on the specific locations, "hotspots", frequented by KPs in Mauritius. Data were collected through multiple levels of activity. Key informants provided information about hotspots where KPs congregated and were actively engaged in risky behaviours. Validation of hotspots was done by engaging KPs. A total of 17 248 KP members were estimated spread over 1 964 hotspots in Mauritius. The largest KP was PWID with an estimate of 7 598 (range: 4 091-6 223), followed by 6 223 (range: 5 090-7 456) FSWs, spread over 694 and 731 hotspots respectively. A total of 2 020 (range: 1 595-2 446) MSM and 294 geographic MSM hotspots, and 1 407 TGSWs (range: 1 165-1 649) distributed over 245 hotspots. This research provided Mauritius with validated KPs size estimations and provided the first national data on KP hotspots and operational dynamics. The use of these data will strengthen HIV prevention, intervention, and programme planning in the country through focusing efforts to systematically target high-risk areas.