New study highlights unacceptably high global prevalence of syphilis among men who have sex with men

Syphilis, a sexually transmitted infection (STI), is caused by the bacteria Treponema pallidum.

The study lead by the London School of Hygiene and Tropical Medicine, London, UK and published in the Lancet Global Health presents the first global syphilis prevalence estimate among men who have sex with men.

Findings from this global review show that men who have sex with men have high burden of syphilis infection, with significant variation across countries and regions. 

The global pooled prevalence of syphilis among men who have sex with men was 7.5% during 2000-2020 (95% CI: 7.0-8.0), as compared to the most recent estimate of syphilis among men in the general population in 2016, 0.5% (95% UI: 0.4-0.6). The proportion of men who have sex with men with syphilis was highest in settings where HIV prevalence was greater than 5% and in low and -middle income countries (LMIC). 

Sub-analysis showed that pooled prevalence estimates were higher between 2015-2020 compared to the prior 5 years in half of the global regions assessed and several countries are reporting a high and sustained increase in syphilis infection among men who have sex with men.

Globally, there were an estimated 7 million new syphilis infections in 2020. WHO has set ambitious targets to reduce incidence of syphilis by 90% by 2030, but the global response has been slow. 
While there have been modest reductions in congenital syphilis as a result of the scale-up of interventions in antenatal care, such as syphilis screening and treatment for pregnant women, there is an urgent need to galvanize momentum and better serve other priority populations disproportionally impacted by the disease.

Syphilis is preventable and curable, with cost-effective and, in certain contexts, cost-saving interventions. Easy to use and inexpensive point-of-care tests include blood-based rapid tests that produce results in less than 20 minutes, and products that test syphilis and HIV using a single platform. 

Treatment with injectable benzathine penicillin is simple to administer and inexpensive. A major challenge is that populations at higher risk for syphilis, particularly in LMIC, are often not able to access services due to structural barriers, including criminalization, policy and legal barriers, discrimination and violence. As recommended by WHO, governments should address these structural barriers as a priority.

“This first review of global syphilis prevalence among men who have sex with men highlights the urgent need to improve access to syphilis testing, treatment and prevention services," said Dr Meg Doherty, Director of WHO’s Department of Global HIV, Hepatitis and STI Programmes. "Stakeholders must address structural barriers, like discrimination and violence; improve sexuality education, and expand access and delivery of syphilis testing and immediate treatment for all populations at higher risk of infection.”