AUTHOR=Mota María Inés , Vázquez Sylvia , Cornejo Cecilia , D'Alessandro Bruno , Braga Valeria , Caetano Ana , Betancor Laura , Varela Gustavo 

TITLE=Does Shiga Toxin-Producing Escherichia coli and Listeria monocytogenes Contribute Significantly to the Burden of Antimicrobial Resistance in Uruguay?

JOURNAL=Frontiers in Veterinary Science

VOLUME=7

YEAR=2020

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2020.583930

DOI=10.3389/fvets.2020.583930

ISSN=2297-1769

ABSTRACT=<p>Shiga toxin-producing <italic>Escherichia coli</italic> (STEC) and <italic>Listeria monocytogenes</italic> are worldwide recognized zoonotic pathogens. Recent reports have emerged about the circulation of antimicrobial-resistant STEC and <italic>L. monocytogenes</italic> isolates. To assess the frequency of antimicrobial resistance and related genes in these pathogens, we studied 45 STEC and 50 <italic>L. monocytogenes</italic> isolates locally recovered from different sources. Antimicrobial susceptibility testing was performed by disk-diffusion method, and the genomic sequences of three selected STEC and from all 50 <italic>L. monocytogenes</italic> isolates were analyzed for antibiotic resistance genes. Four STEC and three <italic>L. monocytogenes</italic> isolates were phenotypically resistant to at least one of the antibiotics tested. Resistance genes <italic>aph</italic>(3″)-Ib, <italic>aph</italic>(3′)-Ia, <italic>aph</italic>(6)-Id, <italic>bla</italic><sub><italic>T</italic></sub><sub>EM−1B</sub>, <italic>sul</italic>2, <italic>mef</italic> (A), and <italic>tet(</italic>A) were found in a human STEC ampicillin-resistant isolate. All <italic>L. monocytogenes</italic> isolates harbored f<italic>osX, lin, mdr</italic>L, <italic>lde fepA</italic>, and <italic>norB</italic>. Overall resistance in <italic>L. monocytogenes</italic> and STEC was low or middle. However, the high load of resistance genes found, even in susceptible isolates, suggests that these pathogens could contribute to the burden of antimicrobial resistance.</p>