Emmanuel F, et al. - Data collected as part of the fifth round of integrated biological and behavioural surveillance was assessed with the aim to ascertain the prevalence and factors linked with HIV infection among female sex workers (FSWs) in Pakistan. Of 5,728 invited FSWs for participation, 68 refused to participate (refusal rate = 1.2%). Among 5,660 FSW participants, HIV seropositivity was detected in 121 (weighted HIV prevalence 2.3%; 95% CI 1.9% to 2.7%) mostly concentrated within cities in Sindh. In multivariate analysis, following factors were identified to be independently linked with HIV seropositivity: uneducated/illiterate, directly dealing with clients without a pimp, non-use of condom with clients, having sexual contact with people who inject drugs and non-participation in HIV programmes. Findings emphasize the necessity for scaling up of HIV prevention programs to improve coverage, particularly among FSWs with these risk factors.