Trends in Unprotected Oral Sex Among Individuals Diagnosed With Early Syphilis in Ohio's Three Most Populated Counties, 2009 to 2015

Abstract

Background Surveillance data show increasing early syphilis (ES) incidence in Ohio. Compared with anal and vaginal sex, unprotected oral sex may be an underappreciated risk factor for ES transmission. We report trends in unprotected oral sex among ES cases in Ohio's three most populated counties. Methods Early syphilis incidence rates were calculated using surveillance data from Franklin, Hamilton, and Cuyahoga County trends in ES incidence (January 2009–May 2015), and proportion of patients who never used condoms during oral, anal, and vaginal sex in the previous 12 months was determined. Results In Franklin County, ES incidence increased from 17.9 to 42.1 cases per 100,000 (P < 0.001) and so did the proportion of patients who never used condoms during oral sex (P < 0.001), but not during anal (P = 0.19) or vaginal (P = 0.37) sex. In Hamilton County, ES incidence decreased from 49.2 to 19.2 cases per 100,000 (P < 0.001) and so did the proportion of patients who never used condoms during oral (P < 0.001) and anal (P = 0.0004) sex, but not during vaginal sex (P = 0.14). In Cuyahoga County, overall ES incidence decreased from 12.6 to 8.4 cases per 100,000 (P = 0.0013) but has increased since 2013. There has been a significant increase in the proportion of patients who never used condoms during oral sex (P < 0.001), but not during anal (P = 0.52) or vaginal (P = 0.65) sex. Conclusions In Ohio counties where ES incidence is increasing, the proportion of patients who never used condoms during oral sex is increasing. Where ES incidence is decreasing, the opposite trend was observed. Additional research should help define the role of oral sex in current ES epidemics.