Expansion oftetM-carryingNeisseria gonorrhoeaein the US, 2018-2024

ABSTRACT Doxycycline use for bacterial sexually transmitted infections (STIs) increased in recent years due to changes in treatment guidelines, the shortage of benzathine penicillin for treatment of syphilis, and adoption of doxycycline post-exposure prophylaxis. While this increased use is expected to select for doxycycline resistance, particularly in Neisseria gonorrhoeae, the impact has been unclear. Here, we analyzed over 14,000 publicly available N. gonorrhoeae genome sequences from 2018-2024 generated through the US Centers for Disease Control and Prevention N. gonorrhoeae surveillance system, assessed the distribution of tetM, a plasmid-borne gene that confers high-level (MIC ≥ 16µg/mL) tetracycline resistance, and evaluated the spatial, temporal, and evolutionary dynamics of its spread. The proportion of Neisseria gonorrhoeae carrying tetM increased from below 10% in 2020 to over 35% in 2024. Phylogenetic analysis revealed four major clades that have rapidly expanded. Two of these lineages also carry penA alleles that increase resistance to ceftriaxone. The strength of selection for tetracycline resistance, as indicated by its increased proportion and the growth of major tetM-carrying lineages, suggests a favorable environment for N. gonorrhoeae strains spreading globally that carry tetM and resistance to multiple other antibiotics used in gonorrhea treatment. Competing Interest Statement The authors have declared no competing interest. Funding Statement This work was supported by NIH R01 AI132606 and R01 AI153521 to Y.H.G Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability The data required to reproduce this analysis is publicly available through the NCBI Pathogen Detection database with detailed instructions available in the Supplementary Appendix.