Decreases in Reported Sexually Transmitted Infections During the Time of COVID-19 in King County, WA: Decreased Transmission or Screening?

Abstract

In response to the COVID-19 pandemic, Washington State's Stay Home, Stay Healthy (SHSH) order was implemented on March 24, 2020. We hypothesized that pandemic mitigation measures might reduce sexually transmitted infection (STI) screening and/or transmission. We used King County, WA STI surveillance and sexual health clinic (SHC) data from January 1, 2019, to July 31, 2020. We calculated mean weekly case counts for gonorrhea, primary and secondary (P&S) syphilis, male urethral gonorrhea, and early latent (EL) syphilis for 3 periods in 2020: pre-SHSH (January 1-March 23), SHSH (March 24-June 5), and reopening (June 6-July 31). Primary and secondary syphilis and male urethral gonorrhea were used as proxies for sexual behavior, and EL syphilis was used as a proxy for STI screening. We compared SHC visits (2019 vs. 2020) and SHC gonorrhea treatment practices (across 2020 periods). Compared with January to July 2019, from January to July 2020, reported cases of gonorrhea, male urethral gonorrhea, P&S syphilis, and EL syphilis decreased by 9%, 5%, 16%, and 22%, respectively. Mean weekly case counts of gonorrhea, male urethral gonorrhea, and EL syphilis decreased pre-SHSH to SHSH, but all returned to pre-SHSH levels during reopening. Sexual health clinic visits during SHSH were 55% lower in 2020 than in 2019. In the SHC during SHSH, ceftriaxone treatment of gonorrhea decreased, whereas cefixime/cefpodoxime treatment and gonorrhea treatment with no testing increased. Decreases in reported STIs concurrent with COVID-19 SHSH may reflect a true decline in STI transmission. However, the larger decreases in asymptomatic infections indicate that much of the observed decrease was likely due to decreased screening.