Periodic presumptive treatment of curable sexually transmitted infections among sex workers: a systematic review.
Unprotected sex work remains a major driver of HIV/sexually transmitted infection (STI) epidemics in many countries. STI treatment can lower disease burden, complications and prevalence of HIV cofactors. Periodic presumptive treatment (PPT) has been used with sex workers to reduce their high burden of largely asymptomatic STIs. The objective of this review is to assess benefits and harms of PPT among female sex workers. We searched MEDLINE for studies related to sex work and STIs during 1990-2010, extracted data from eligible studies in duplicate and conducted meta-analysis by study design using random effects models. Two thousand, three hundred and fifteen articles were screened, 18 studies met inclusion criteria and 14 were included in meta-analyses. One published randomized controlled trial (RCT) reported significant reductions of gonorrhoea (Neisseria gonorrhoeae) [rate ratio (RR) 0.46, 95% confidence interval (CI) 0.31-0.68] and chlamydia (Chlamydia trachomatis) (RR 0.38, 95%CI 0.26-0.57), but no effect on serologic syphilis (RR 1.02, 95%CI 0.54-1.95). Similar results were seen for N. gonorrhoeae and C. trachomatis in pooled analyses, including data from one unpublished RCT and across study designs, and correlated with initial prevalence (R(2) = 0.155). One observational study reported genital ulcer disease (GUD) declines in sex workers, and two reported impact among male client populations for N. gonorrhoeae [odds ratio (OR) 0.60, 95% CI 0.38-0.94], C. trachomatis (OR 0.47, 95% CI 0.31-0.71) and GUD (OR 0.21, 95% CI 0.11-0.42). No studies reported evidence of risk compensation or antibiotic resistance. PPT can reduce prevalence of gonorrhoea, chlamydia and ulcerative STIs among sex workers in whom prevalence is high. Sustained STI reductions can be achieved when PPT is implemented together with peer interventions and condom promotion. Additional benefits may include impact on STI and HIV transmission at population level.