Determining the screening frequency for sexually transmitted infections for people who use HIV pre-exposure prophylaxis: A systematic review and meta-analysis

Background: Although the World Health Organization (WHO) recommends ‘frequent’ screening of sexually transmitted infections (STI) for people who use pre-exposure prophylaxis (PrEP) for HIV, there is no evidence for optimal frequency.

Methods: We searched five databases and used random-effects meta-analysis to calculate pooled estimates of STI test positivity. We narratively synthesized data on secondary outcomes, including adherence to recommended STI screening frequency and changes in STI epidemiology.

Findings: Of 7477 studies, we included 38 for the meta-analysis and 11 for secondary outcomes. With 2–3 monthly STI screening, the pooled positivity was 0·20 (95% confidence interval (CI):0·15–0·25) for chlamydia, 0·17 (95% CI:0·12–0·22) for gonorrhoea and 0·07 (95% CI:0·05–0·08) for syphilis. For chlamydia and gonorrhoea, the positivity was approximately 50% and 75% lower, respectively, in studies that screened 4–6 monthly versus 2–3 monthly. There was no significant difference in the positivity for syphilis in studies that screened 4–6 monthly compared to 2–3 monthly. Adherence of clients to recommended screening frequency varied significantly (39–94%) depending on population and country. Modelling studies suggest more frequent STI screening could reduce incidence.

Interpretation: Though more frequent STI screening could reduce delayed diagnoses and incidence, there remain significant knowledge gaps regarding the optimal STI screening frequency.

• Epidemiology and Determinants of Health
  • Epidemiology
• Population(s)
  • General HIV- population
• Prevention, Engagement and Care Cascade
  • Prevention
• Prevention
  • Biomedical interventions
• Co-infections
  • Chlamydia
  • Gonorrhea
  • Syphilis