Surveillance of the antimicrobial susceptibility and molecular characteristics of Neisseria gonorrhoeae isolates collected in Changsha, China from 2016 to 2021.

Antibiotic treatment is critical for gonorrhea-infected individuals and for preventing disease transmission. The aim of this study was to analyze the antimicrobial susceptibility and molecular epidemiological characteristics of Neisseria gonorrhoeae isolates in Changsha, China. A total of 271 N. gonorrhoeae isolates collected from clinical laboratories of two hospitals between 2016 and 2021 were analyzed for antimicrobial susceptibility using the agar dilution method. N. gonorrhoeae multi-antigen sequence typing (MG-MAST) was conducted for genotyping, and phylogenetic analysis was determined using porB and tbpB sequences. Results showed that ciprofloxacin, tetracycline and penicillin were at high levels of antimicrobial resistance, which were no longer recommended to treat gonorrhea. All isolates were susceptible to spectinomycin. However, in 2016-2021, a total of 15 (5.5%) ceftriaxone-resistant strains and 31 (11.4%) isolates with decreased susceptibility to ceftriaxone were found and the resistance rate of azithromycin in 2016-2017 had reached 7.1%. Epidemiologically, mosaic penA allele was identified in all ceftriaxone-resistant isolates. The most prevalent NG-MAST ST was ST5061. Phylogenetic analysis suggested that the resistant isolates were not clustered alone. This study, though performed locally, raises the alert on gonorrhea medication that ceftriaxone may not be adequate as a first-line treatment for gonorrhea in Changsha.