Genomic Surveillance of Neisseria gonorrhoeae in the Philippines from 2013-2014

Antimicrobial-resistant Neisseria gonorrhoeae is a major threat to public health, and of particular concern in the Western Pacific Region, where the incidence of gonorrhoea is high. The Antimicrobial Resistance Surveillance Program (ARSP) has been capturing information on resistant gonorrhoea since 1996, but studies of the genomic epidemiology of gonorrhoea in the Philippines are lacking. We sequenced the whole genomes of 21 N. gonorrhoeae isolates collected in 2013-2014 by the ARSP. The multi-locus sequence type, multi-antigen sequence type, presence of antimicrobial resistance (AMR) determinants, and relatedness between the isolates were all derived from the sequence data. The concordance between phenotypic and genotypic resistance was also determined. Ten out of 21 isolates were resistant to penicillin, ciprofloxacin and tetracycline, mostly linked to the presence of blaTEM gene, the S91F mutation in the gyrA gene, and the tetM gene, respectively. None of the isolates were resistant to azithromycin, ceftriaxone or cefixime, although we identified the A24-deletion in the mtrR promoter in one isolate. The concordance between phenotypic and genotypic resistance was 92.38% overall for 5 antibiotics in 4 classes. Despite the small number of isolates studied, they were genetically diverse, as shown by the sequence types, the NG-MAST types and the tree. Comparison with global genomes placed the Philippine genomes within global Lineage A and led to the identification of an international transmission route. This first genomic survey of N. gonorrhoeae isolates collected by ARSP will be used to contextualize ongoing prospective surveillance, and it highlights the importance of genomic surveillance in the Western Pacific and other endemic regions to understand the spread of drug-resistant gonorrhoea worldwide.