Effect of COVID‐19 Pandemic on Epidemiology and Antimicrobial Susceptibility of <i>Campylobacter</i> Species, <i>Salmonella enterica</i> and <i>Yersinia enterocolitica</i> in Southwest Finland 2018–2022

Abstract

<p>This study investigated the effect of the COVID-19 pandemic on the epidemiology and antimicrobial susceptibility of fecal <em>Campylobacter</em> spp.<em>, Salmonella enterica</em>, and <em>Yersinia enterocolitica</em> strains in Southwest Finland from 2018 to 2022. Results show that the number of travel-associated <em>S. enterica</em> and <em>Campylobacter</em> spp. declined markedly from autumn 2019 to autumn 2020 and have recovered gradually. Antimicrobial susceptibility testing was performed on bacterial strains isolated from PCR-positive fecal specimens. Resistance patterns fluctuated throughout the study period. Among <em>C. jejuni</em>, ciprofloxacin resistance averaged 58% in domestic (<em>n</em> = 155) and 88% travel-associated (<em>n</em> = 10) strains, while tetracycline resistance averaged 36% and 63%, respectively; erythromycin resistance was not detected. In <em>S. enterica</em>, resistance averaged 42% and 33% to ampicillin, 33% and 45% to fluoroquinolones, 4% and 6% to cefotaxime, and 0% and 2% to co-trimoxazole, in domestic (<em>n</em> = 24) and travel-associated (<em>n</em> = 32) strains, respectively. Among domestic <em>Y. enterocolitica</em> strains (<em>n</em> = 64), resistance averaged 7% to co-trimoxazole, 2% to ciprofloxacin, and 1% to cefotaxime; no travel-associated strains were reported. This study shows that lockdowns due to the COVID-19 pandemic decreased the number of diagnosed enteropathogens and limited the emergence of resistant strains. Thus, our results reaffirm that travel remains the primary source of <em>S. enterica</em> infections in Finland.<br></p>