Syphilis infection prevalence in the Middle East and North Africa: a systematic review and meta-analysis

Abstract

Background: Syphilis is a sexually transmitted infection (STI) that can be prevented and effectively treated; yet it continues to be a cause of morbidity and mortality worldwide. There is a limited understanding of the epidemiology of syphilis in the Middle East and North Africa (MENA) region.

Methods: A systematic review conducted up to April 30, 2024 assessed the prevalence of syphilis and followed PRISMA guidelines, without language and date restrictions. Syphilis infection was categorized based on the diagnostic test type, distinguishing between current and lifetime infections. Pooled mean prevalence estimates were determined through random-effects meta-analyses. Random-effects meta-regression analyses were conducted to investigate sources of heterogeneity between studies and identify factors associated with syphilis prevalence.

Findings: The review identified 643 studies based on close to 38 million syphilis tests in the 24 MENA countries. The pooled prevalence for probable current syphilis infection was 0.004% (95% CI: 0.001%-0.025%) among blood donors, 0.48% (95% CI: 0.22%-0.82%) in the general population (pregnant women and other general population groups), 2.76% (95% CI: 1.51%-4.35%) in populations at intermediate risk, 4.18% (95% CI: 2.08%-6.89%) among STI clinic attendees, 12.58% (95% CI: 8.45%-17.35%) among female sex workers, and 22.52% (95% CI: 12.73%-34.06%) among men who have sex with men and transgender people. Meta-regression analyses explained 62% of the prevalence variation and indicated a hierarchical pattern in prevalence by population group, higher prevalence among men, considerable subregional variability, and an annual decline of 3% in prevalence among general population groups and 8% among populations at high risk.

Interpretation: Syphilis prevalence in MENA is comparable to global levels, emphasizing a considerable yet often overlooked disease burden with implications for reproductive health and social well-being. The observed rate of decline in syphilis prevalence and the current response fall short of the global targets. Action is required to control syphilis and mitigate its impact, especially in most affected populations.

Funding: Qatar Research, Development, and Innovation Council (ARG01-0524-230273); Qatar National Research Fund (NPRP grant number 9-040-3-008).

Keywords: Middle East and North Africa; Prevalence; Syphilis; Treponema pallidum.

Fig. 1

PRISMA flowchart depicting the study selection process for the systematic review of syphilis in the Middle East and North Africa. IBBSS: integrated biobehavioral surveillance survey, UNAIDS: United Nations Programme on HIV/AIDS, WHO: World Health Organization.