Background The epidemiology of syphilis, and therefore the population most impacted, differs between countries. Many developed countries have reported an increase in syphilis notifications among men who have sex with men (MSM) over the past decade.
Methods: The rates of syphilis notifications between 2000 and 2013 in the 31 countries categorised by the Organisation for Economic Co-operation and Development (OECD) as high income were investigated. Data was taken primarily from published national surveillance reports, and a male-to-female ratio substantially greater than two in syphilis notifications was taken as a proxy for the infection being disproportionately diagnosed in MSM.
Results: Data was available for 27 high-income countries. The male-to-female ratio exceeded two in all but four countries. This ratio significantly increased across all geographical areas over time. Globally, the male-to-female ratio in these countries increased from 4.1 in 2000 to 7.9 in 2013 (P=0.001). Furthermore, the proportion of male cases reported as being among MSM increased over time from 26.8% to 55.0% between 2000 and 2013 (P<0.001).
Conclusion: These data show that in countries with high income, there is a near universal finding of increasing rates of syphilis in MSM. It is therefore clear that no country has identified an effective method to control syphilis in this population.