We described and characterized Shiga-toxin-producing Escherichia coli (STEC) strains with high levels of resistance to azithromycin isolated in France between 2004 and 2020. Nine of 1,715 (0.52%) STEC strains were resistant to azithromycin, with an increase since 2017. One isolate carried a plasmid-borne mef(C)-mph(G) gene combination, described here for the first time for E. coli. Azithromycin resistance, although rare, needs consideration, as this treatment may be useful in cases of STEC infection.
Keywords: EHEC; azithromycin resistance; fosfomycin; macrolide resistance; macrolides; mef(C)-mph(G); mph(A); mph(B); phosphorylases; rifaximin.