Prevalence, antibiogram and virulence characterization of Vibrio isolates from fish and shellfish in Egypt: a possible zoonotic hazard to humans

Aims Infection of seafood with pathogenic species of the genus Vibrio causes human food-borne illnesses. This study was executed to examine the antimicrobial resistance phenotypes, biofilm-forming capability and virulence-associated genes of Vibrio from fish and shellfishes. Methods and results Three hundred fresh water and marine fish and shellfish samples were collected from wet markets and supermarkets in Mansoura, Egypt. Bacteriological examination and PCR amplification identified 92 Vibrio spp., including 42 Vibrio parahaemolyticus and 50 Vibrio alginolyticus isolates from the examined fish and shellfish (infection rate: 30 center dot 67%). However, V. vulnificus was not found in this study. Vibrio spp. exhibited variable frequencies of antimicrobial resistance with higher percentages to ampicillin and penicillin. Multidrug resistance (MDR) was detected in 69 center dot 04 and 38% of V. parahaemolyticus and V. alginolyticus respectively. PCR testing of virulence genes, tdh, trh and tlh revealed the presence of tlh and trh in 100 and 11 center dot 9% of V. parahaemolyticus isolates respectively and none of V. alginolyticus carried any of these genes. Biofilm-forming capability was displayed by 76% of V. parahaemolyticus and 73 center dot 8% of V. alginolyticus isolates. Both V. parahaemolyticus and V. alginolyticus showed nonsignificant weak positive correlations (r < 0 center dot 4) between antimicrobial pairs belonging to different classes; however, a significant positive correlation (P <0 center dot 05) between trh and resistance to erythromycin (r = 0 center dot 45) and imipenem (r = 0 center dot 38) was only identified in V. parahaemolyticus. Conclusions This study reports the existence of MDR strains of V. parahaemolyticus and V. alginolyticus from the common types of fishes and shellfishes in Egypt. Furthermore, the presence of virulence genes in these isolates and the ability to produce a biofilm in vitro pose potential health hazards to consumers. Significance and Impact of the Study Frequent monitoring of seafood for the presence of Vibrio spp. and their antimicrobial susceptibility, virulence determinants and biofilm-forming capability is important for assessing the risk posed by these organisms to the public and for improving food safety.

Automated summary

This study examined the antimicrobial resistance, biofilm-forming capability, and virulence-associated genes of Vibrio strains isolated from fish and shellfish. The results revealed the presence of multidrug-resistant strains, virulence genes, and potential health hazards associated with biofilm formation in these isolates.