Rapid emergence of extensively drug-resistant Shigella sonnei in France

Lefevre, S.; Njamkepo, E.; Feldman, S.; Ruckly, C.; Carle, I.; Lejay-Collin, M.; Fabre, L.; Yassine, I.; Frezal, L.; Pardos de la Gandara, M.; Fontanet, A.; Weill, F.-X.

doi:10.1101/2022.09.07.506808

bioRxiv · 10.1101/2022.09.07.506808

Rapid emergence of extensively drug-resistant Shigella sonnei in France

Lefevre, S.·Njamkepo, E.·Feldman, S.·Ruckly, C.·Carle, I.·Lejay-Collin, M.·Fabre, L.·Yassine, I.·Frezal, L.·Pardos de la Gandara, M.·Fontanet, A.·Weill, F.-X.

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Abstract

Shigella sonnei, the main cause of bacillary dysentery in high-income countries, has become increasingly resistant to antibiotics. We monitored the antimicrobial susceptibility of 7,121 S. sonnei isolates collected in France between 2005 and 2021. We identified a dramatic increase in the proportion of extensively drug-resistant (XDR) isolates (i.e., simultaneously resistant to ciprofloxacin, third-generation cephalosporins and azithromycin), to 22.3% of all S. sonnei isolates in 2021. Our genomic analysis identified 13 different clusters of XDR isolates descended from a ciprofloxacin-resistant sublineage originating from South Asia. The 164 XDR isolates detected were resistant to azithromycin, principally through a pKSR100-like plasmid, and to third-generation cephalosporins through various genes and plasmids. This rapid emergence of XDR S. sonnei in different transmission networks, particularly among men who have sex with men, is a matter of concern, and good laboratory-based surveillance of Shigella infections will be crucial for informed decision-making and appropriate public health action.

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Lefevre, S., Njamkepo, E., Feldman, S., Ruckly, C., Carle, I., Lejay-Collin, M., Fabre, L., Yassine, I., Frezal, L., Pardos de la Gandara, M., Fontanet, A., Weill, F.-X.. 2022-09-09. Rapid emergence of extensively drug-resistant Shigella sonnei in France. https://doi.org/10.1101/2022.09.07.506808

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