Investigation of Early Syphilis Trends Among Men Who Have Sex With Men to Identify Gaps in Screening and Case-Finding in Baltimore City, Maryland
Syphilis incidence is increasing across the United States among men who have sex with men (MSM). Early latent (EL) versus primary and secondary (P&S) syphilis may be an indicator of delayed diagnosis and increased opportunity for transmission. To inform syphilis control strategies and identify potential gaps in case finding, we described recent syphilis trends among MSM and compared characteristics of syphilis cases by diagnosis stage.Methods
We used public health surveillance data on P&S and EL syphilis diagnoses reported to the Baltimore City Health Department between 2009 and 2015. Differences across diagnosis stage were assessed using Cochran-Armitage and χ2 tests.Results
Between 2009 and 2015, Baltimore City Health Department received 2436 reports of P&S and EL diagnoses. The majority (61%) of reports were among MSM, among whom 86% were black and 67% were human immunodeficiency virus (HIV)-infected. During this period, P&S and EL syphilis increased by 85% and 245%, respectively (P < 0.0001). MSM with EL versus P&S syphilis were similarly likely to be Black, more likely to be older (P < 0.05), HIV coinfected (P < 0.001), and diagnosed in private health care settings (P < 0.0001), but less likely to report multiple (P < 0.001) and anonymous sex partners (P < 0.001).Conclusions
In Baltimore City, syphilis diagnoses, particularly EL diagnoses, are increasing rapidly and are concentrated among Black HIV-infected MSM. Significant gaps in identifying MSM with P&S syphilis may exist, specifically among HIV-infected MSM, and those diagnosed in private health care settings. Strategies to address these gaps may include local guidelines and provider education to screen MSM more frequently than CDC currently recommends and regardless of HIV status or risk.