Syphilis Prevalence Among People Living With and Without HIV in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Background: Syphilis is a curable sexually transmitted infection that, untreated, is associated with significant morbidity and mortality. In people living with HIV (PLWH), syphilis carries greater risks of disease progression. We estimated syphilis prevalence among PLWH in the general population in sub-Saharan Africa and compared the prevalence among PLWH and without HIV.

Methods: We searched for studies published January 1, 2011, to March 28, 2022, reporting syphilis prevalence among PLWH in sub-Saharan Africa (PROSPERO No. CRD42020167328). We excluded studies in high-risk subpopulations. We estimated pooled syphilis prevalence among PLWH using random-effects modeling and compared the prevalence with people without HIV when included in the same study. We examined influences of region, study setting, and test type in subgroup analyses.

Results: We identified 926 studies; 53 were included in the meta-analysis. Pooled syphilis prevalence among PLWH was 7.3% (95% confidence interval [CI], 6.3%-8.5%). Prevalence differed by region: 3.1% (95% CI, 2.2%-4.0%) in Southern, 5.5% (95% CI, 2.3%-9.3%) in West/Central, and 10.5% (95% CI, 8.0%-13.1%) in Eastern Africa. Prevalence also differed by study setting: 13.8% (95% CI, 5.7%-23.0%) in sexual and reproductive health/sexually transmitted infection care, 8.7% (95% CI, 5.0%-12.8%) in HIV care, 7.1% (95% CI, 5.8%-8.5%) in antenatal care, and 3.8% (95% CI, 2.0%-5.8%) in household/community-based settings. Syphilis prevalence was higher among PLWH than without HIV (relative risk, 3.5; 95% CI, 2.8-4.5).

Conclusions: Syphilis is highly prevalent among PLWH in sub-Saharan Africa and is more common among PLWH than without HIV. Integration of syphilis screening and management into HIV care may reduce complications of HIV-syphilis coinfection among PLWH in sub-Saharan Africa.