Prevalence and Genomic Characterization of Vibrio parahaemolyticus Isolated from a Vast Amount of Aquatic Products in Huzhou, China

Vibrio parahaemolyticusis the leading bacterial cause of gastroenteritis associated with aquatic food consumption globally. This study aimed to determine the prevalence ofV. parahaemolyticusin aquatic foods from Huzhou and to identify the serotypes, antimicrobial resistance, virulence factors, and genetic relatedness of the strains. A total of 306 isolates were detected from 1314 aquatic food samples from 2022 to 2024. The results indicated that the most prevalent serotypes were O1:KUT (17.0%), O2:K28 (13.7%), and O2:KUT (13.1%). Multilocus sequence typing analysis divided the 306 isolates into 175 sequence types (STs), and the predominant sequence type was ST864 (3.3%). Antimicrobial susceptibility tests showed that 2.6% of isolates were multidrug resistant. High resistance was observed to ampicillin (64.7%) and streptomycin (44.4%). A total of seven antimicrobial categories of resistance genes were identified, and the resistance geneblaCARBwas detected in all isolates. The virulence genestdhandtrhwere found in 16 (5.2%) and 12 (3.9%) isolates, respectively. In addition, we observed that all the 306V. parahaemolyticusisolates encode type III secretion systems 1. The phylogenomic analysis based on the whole-genome sequence revealed that the 306 isolates were divided into four clusters. Our findings broaden perspectives onV. parahaemolyticusgenetic diversity and enhance our ability to assess the potential risks of its spread.