Isolation of extended-spectrum β-lactamase-producing Escherichia coli from Japanese red fox (Vulpes vulpes japonica)

Antimicrobial resistance is a global concern requiring a one-health approach. Given wild animals can harbor antimicrobial-resistant bacteria (ARB), we investigated their presence in 11 fecal samples from wild animals using deoxycholate hydrogen sulfide lactose agar with or without cefotaxime (CTX, 1 mg/L). Thus, we isolated CTX-resistant Escherichia coli from two Japanese red fox fecal samples. One strain was O83:H42-ST1485-fimH58 CTX-M-55-producing E. coli carrying the genes aph(3 '')-Ib, aph(3 ')-Ia, aph(6)-Id, mdf(A), sitABCD, sul2, tet(A), and tet(B), whereas the other was O25:H4-ST131-fimH30 CTX-M-14-producing E. coli carrying mdf(A) and sitABCD and showing fluoroquinolone resistance. Thus, the presence of extended-spectrum beta-lactamase producers in wild foxes suggests a spillover of ARB from human activities to these wild animals.