AUTHOR=Hirshfeld Brady , Lavelle Kurtis , Lee Katie Yen , Atwill Edward Robert , Kiang David , Bolkenov Bakytzhan , Gaa Megan , Li Zhirong , Yu Alice , Li Xunde , Yang Xiang 

TITLE=Prevalence and antimicrobial resistance profiles of Vibrio spp. and Enterococcus spp. in retail shrimp in Northern California

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1192769

DOI=10.3389/fmicb.2023.1192769

ISSN=1664-302X

ABSTRACT=<p>Shrimp is one of the most consumed seafood products globally. Antimicrobial drugs play an integral role in disease mitigation in aquaculture settings, but their prevalent use raises public health concerns on the emergence and spread of antimicrobial resistant microorganisms. <italic>Vibrio</italic> spp., as the most common causative agents of seafood-borne infections in humans, and <italic>Enterococcus</italic> spp., as an indicator organism, are focal bacteria of interest for the monitoring of antimicrobial resistance (AMR) in seafood. In this study, 400 samples of retail shrimp were collected from randomly selected grocery stores in the Greater Sacramento, California, area between September 2019 and June 2020. The prevalence of <italic>Vibrio</italic> spp. and <italic>Enterococcus</italic> spp. was 60.25% (241/400) and 89.75% (359/400), respectively. Subsamples of <italic>Vibrio</italic> (<italic>n</italic> = 110) and <italic>Enterococcus</italic> (<italic>n</italic> = 110) isolates were subjected to antimicrobial susceptibility testing (AST). <italic>Vibrio</italic> isolates had high phenotypic resistance to ampicillin (52/110, 47.27%) and cefoxitin (39/110, 35.45%). <italic>Enterococcus</italic> were most frequently resistant to lincomycin (106/110, 96.36%), quinupristin-dalfopristin (96/110, 87.27%), ciprofloxacin (93/110, 84.55%), linezolid (86/110, 78.18%), and erythromycin (58/110, 52.73%). For both <italic>Vibrio</italic> and <italic>Enterococcus</italic>, no significant associations were observed between multidrug resistance (MDR, resistance to ≥3 drug classes) in isolates from farm raised and wild caught shrimp (<italic>p</italic> &gt; 0.05) and in isolates of domestic and imported origin (<italic>p</italic> &gt; 0.05). Whole genome sequencing (WGS) of a subset of <italic>Vibrio</italic> isolates (<italic>n</italic> = 42) speciated isolates as primarily <italic>V. metschnikovii</italic> (24/42; 57.14%) and <italic>V. parahaemolyticus</italic> (12/42; 28.57%), and detected 27 unique antimicrobial resistance genes (ARGs) across these isolates, most commonly <italic>qnrVC6</italic> (19.05%, 8/42), dfrA31 (11.90%, 5/42), dfrA6 (9.5%, 4/42), <italic>qnrVC1</italic> (9.5%, 4/42). Additionally, WGS predicted phenotypic resistance in <italic>Vibrio</italic> isolates with an overall sensitivity of 11.54% and specificity of 96.05%. This study provides insights on the prevalence and distribution of AMR in <italic>Vibrio</italic> spp. and <italic>Enterococcus</italic> spp. from retail shrimp in California which are important for food safety and public health and exemplifies the value of surveillance in monitoring the spread of AMR and its genetic determinants.</p>