The Emerging Intersection Between Injection Drug Use and Early Syphilis in Nonurban Areas of Missouri, 2012–2018

Background The national rate of syphilis has increased among persons who inject drugs (PWID). Missouri is no exception, with increases in early syphilis (ES), congenital syphilis, and PWID, especially in nonurban counties. Methods Disease intervention specialist records for ES cases in Missouri (2012–2018) were examined. Drug use was classified as injection drug use (IDU) (opioid or methamphetamine) or non-IDU (opioid, methamphetamine, or cocaine). Rates were compared based on residence, sex of sex partner, and drug use. Results Rates of ES in Missouri increased 365%, particularly in small metropolitan and rural areas (1170%). Nonurban areas reported a higher percentage of persons with ES who used injection drugs (12%–15%) compared with urban regions (2%–5%). From 2012 to 2018, women comprised an increasing number of ES cases (8.3%–21%); 93% of women were of childbearing age. Increasingly more women in rural areas with ES also reported IDU during this time (8.4%–21.1%). Conclusions As syphilis increases in small metropolitan and rural regions, access to high-quality and outreach-based sexual health services is imperative. Healthcare policy to equip health departments with harm reduction services and drug treatment resources offers an opportunity to impact both syphilis increases as well as health outcomes associated with IDU.