Antimicrobial Resistance Profiling and Genome Analysis of the penA-60.001 Neisseria gonorrhoeae Clinical Isolates in China in 2021.

Abstract

N. gonorrhoeae antimicrobial resistance (AMR) is an urgent public health threat. With dissemination of FC428-related clones, the efficacy of ceftriaxone has become controversial. Agar dilution and whole-genome-sequencing were used to analyze AMR. High-resistance to penicillin (75.2%), tetracycline (87.9%), ciprofloxacin (98.3%), ceftriaxone (8.9%), cefixime (14.3%) and azithromycin (8.6%) was observed among 463 isolates first collected in China in 2021. All penA-60.001 clones exhibited resistance to ceftriaxone or cefixime, and 1/12 of the cases were resistant to azithromycin. ngMAST and ngSTAR of penA-60.001 isolates showed SNPs in porB, tbpB, ponA, gyrA and parC genes were the major causes of different sequence types. MLST-7365 (n = 5) and MLST-1903 (n = 3) were main genotypes, and the other four strains featured MLST-10314, MLST-13871, MLST-7827 and MLST-1600. Furthermore, a set of resistance markers, such as penA, blaTEM-1 and blaTEM-135, and virus factors were detected. Most penA-60.001 strains were fully mixed with global FC428-related clones; 2021-A2 and F89 had the same origin; and 2021-A1 exhibited a unique evolutionary trajectory. Our results provide the first demonstration of extremely severe AMR rates of N.gonorrhoeae in China in 2021, particularly those strains with ceftriaxone decreased-susceptibility, and reveal the sustained transmission of penA-60.001 subclones might further threaten treatment effectiveness.