OBJECTIVES: We compared the number and profile of patients diagnosed with bacterial sexually transmitted infections (STI) before and during the global pandemic.

METHODS: Our study used German claims data provided by AOK PLUS from 01/01/2017-30/06/2021. Continuously insured adults with one inpatient and/or outpatient diagnosis of chlamydia (ICD-10 A55/A56), gonorrhea (A54), or syphilis (A51/A53) were included. The number of new STI cases was assessed quarterly from 2018-2021. A window of 180 days was used to detect new infections, as re-infections are possible.

RESULTS: Overall, 10,222 individuals (11,685 cases) were included. Approximately 60.4% were female, with a mean/median age of 31.9/28.0 years. Only 3.1% received an STI code at baseline.

Chlamydia was the most common STI (77.2%), followed by gonorrhea (13.2%) and syphilis (9.6%). Females recorded more chlamydia (67.4%), while males accounted for a higher share of syphilis (76.9%) and gonorrhea (61.3%) cases. Chlamydia patients were younger at diagnosis (mean/median: 29.9/26.0 years) than gonorrhea (38.4/35.0) and syphilis (41.9/40.0) patients.

From 2018-2021, the number of new chlamydia and syphilis cases fluctuated. A decrease in new gonorrhea cases was observed beginning in Q2 2020 (median/range: 93/83-110 vs. 118/101-137 in the pre-COVID period). The share of women with gonorrhea diagnoses was disproportionately lower during COVID compared to pre-COVID (median/range: 33.7%/27.4-38.1% vs. 42.6%/37.1-47.1% during pre-COVID). While no difference in age profile was observed for gonorrhea or syphilis, the age of patients with chlamydia during COVID was slightly lower (29.2 vs. 31.0 during pre-COVID).

CONCLUSIONS: Fewer women received gonorrhea diagnoses during the COVID period, and the average age of chlamydia patients dropped. Further research is needed to assess whether these trends are suggestive of under-diagnosis or systematic changes in risk-taking behavior during lockdown.