Increase in Neisseria gonorrhoeae infections after ending COVID-19 lockdown measures in Amsterdam, the Netherlands.

Objective: Various European countries noted increasing Neisseria gonorrhoeae (Ng) positivity among cis-gender women and heterosexual men. We assessed changes over time in Ng among men who exclusively have sex with men (MSM), men who exclusively have sex with women (MSW), men who have sex with men and women (MSMW), women and transgender and gender diverse people (TGP).

Methods: We analysed data collected between 2018 and 2023 at the Centre for Sexual Health, Amsterdam. We modelled temporal changes in Ng positivity rates (ie, number of positive results per 100 tests) using relative risk regression with a covariate representing three time periods: pre-COVID-19 (1 January 2018-12 March 2020), during COVID-19 (13 March 2020-1 March 2022), and post-COVID-19 (2 March 2022-31 December 2023).

Results: We included 110 878 consultations pre-COVID-19, 84 917 during COVID-19 and 108 282 post-COVID-19. Positivity rates of Ng went from 12.4% to 13.0% in MSM, 1.7% to 2.3% in MSW, 6.7% to 9.9% in MSMW, 1.3% to 2.9% in women and 8.1% to 10.4% in TGP pre-COVID-19 and post-COVID-19, respectively. Significant increases were observed among MSW (relative risk (RR)=1.31,95% CI 1.12 to 1.53), MSMW (RR=1.47, 95% CI 1.26 to 1.72) and women (RR=2.25, 95% CI 2.03 to 2.49). An increased number of sexual partners and inconsistent condom use were associated with an increased Ng risk.

Conclusion: A substantial relative increase in Ng risk among MSW, MSMW and women, but not MSM or TGP, was observed post-COVID-19. Changes in sexual behaviour were associated with these changes. Continuous surveillance of Ng in heterosexual individuals is needed to monitor changes, alongside implementing prevention strategies for sexually transmitted infections.