Gonococcal antimicrobial susceptibility surveillance in the European Union/ European Economic Area – Summary of results for 2024

During 2024, as in previous years, the European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) followed an annual decentralised and centralised testing model, requesting participating laboratories to collect gonococcal isolates during the period September–November 2024. Susceptibility testing (MIC gradient strip test, mostly Etest, or agar dilution) was performed on all isolates for the following antimicrobials (where available): ceftriaxone, cefixime, azithromycin, ciprofloxacin and tetracycline as well as testing for β-lactamase production for detection of high-level penicillin resistance. Since 2023, testing has been undertaken for tetracycline to monitor the impact of doxycycline post-exposure prophylaxis (doxy-PEP) in the EU/EEA. Decentralised testing took place on the premise that participating laboratories fulfil set quality criteria. In 2024, 24 EU/EEA Member States participated in Euro-GASP, 19 via decentralised testing. Data on 4 516 isolates were submitted to the European Surveillance System (TESSy), 3 371 of which were analysed for this report (trimmed dataset).

Key changes in 2024 compared to the report of the 2023 data:

• Ceftriaxone resistance detected in the analysed 2024 dataset: two ceftriaxone-resistant Neisseria gonorrhoeae isolates were identified in 2024 (Luxembourg and Norway), whereas one was detected in the 2023 dataset; an additional resistant isolate was reported outside the trimmed dataset.
• Extensively drug-resistant (XDR) gonorrhoea was more prominent: all ceftriaxone-resistant isolates detected in 2024 were classified as extensively drug-resistant, increasing concern regarding last-line treatment options.
• Persistently high azithromycin resistance: the proportion of isolates with azithromycin MICs above the epidemiological cut-off (ECOFF) remains high for 2024 (19.1%), even though it has decreased compared to 2023 (23.2%). Isolates with an azithromycin MIC above the ECOFF were detected in 23/24 countries in 2024.
• Ciprofloxacin resistance remains stable, but high: approximately two-thirds of isolates continue to be resistant to ciprofloxacin, indicating a sustained high plateau rather than further increase.
• Implications for doxy-PEP: high tetracycline resistance is explicitly discussed in relation to doxycycline post-exposure prophylaxis, confirming that doxy-PEP is unlikely to reduce gonorrhoea incidence at population level.