Typhoid-causing bacteria have become more resistant to essen
The emergence of increasingly antimicrobial-resistant Salmonella enterica serovar Typhi (S Typhi) threatens to undermine effective treatment and control. A global collection of 4169 S Typhi genome sequences isolated between 1905 and 2018 to investigate the temporal and geographical patterns of emergence and spread of antimicrobial-resistant S Typhi. Our analysis revealed a declining trend of multidrug resistant typhoid. Mutations in the quinolone-resistance determining region (QRDR) of S Typhi have independently arisen and propagated on. Strains with multiple QRDR mutations, including triple mutants with high-level fluoroquinolone resistance, have been increasing in frequency and displacing strains with fewer mutations. Strains containing acrB mutations, conferring azithromycin resistance,and effective population size of these strains has been steadily increasing.

Source: https://www.sciencedirect.com/science/article/pii/S2666524722000933?via=ihub