Detection of antibiotic resistance and virulence genes of Vibrio strains isolated from ready-to-eat shrimps in Delta and Edo States, Nigeria

Aim The current study was conducted to determine the incidence, antibiotic resistance and virulence genes of Vibrio strains isolated from ready-to-eat shrimps in Edo and Delta States, Nigeria. Methods and Results A total of 1440 ready-to-eat shrimp samples were obtained from open markets from November 2016 to October 2017 and analysed using standard culture-based procedures. Overall, our result showed that the ready-to-eat shrimp samples had high mean aerobic mesophilic bacterial count between 3 center dot 543 and 7 center dot 489 log(10) CFU per gram. Vibrio cell densities ranged between 0 center dot 663 and 6 center dot 761 log(10) CFU per gram. From the total samples, 1343/1440 (93 center dot 3%) were positive for Vibrio species where 120 Vibrio isolates were randomly selected and confirmed using genus- and species-specific PCR approach. The PCR identification revealed the presence of Vibrio parahaemolyticus 46 (38 center dot 33%), Vibrio vulnificus 14 (11 center dot 67%), Vibrio fluvialis 12 (10%), Vibrio alginolyticus 8 (6 center dot 67%), Vibrio cholerae 2 (1 center dot 67%), Vibrio mimicus 10 (8 center dot 33%), Vibrio harveyi 3 (2 center dot 5%) and other Vibrio sp. 25 (20 center dot 83%). All Vibrio isolates were sensitive to colistin and gentamycin with varying percentage of resistance to other antibiotics used in the study. Multiple antibiotic-resistant (MAR) index ranged from 0 center dot 08 to 0 center dot 83. The tcp, tdh and trl virulence genes were identified in 95 (79 center dot 2%), 92 (76 center dot 7%) and 95 (79 center dot 2%) of the examined isolates respectively. Antibiotic-resistant genes also revealed the presence of class 1 integrase 75 (62 center dot 5%), sul2 87 (72 center dot 5%), strB 94 (78 center dot 3%) and catB3 68 (56 center dot 7%). Conclusion Our findings revealed that the ready-to-eat shrimps may serve as potential reservoirs and medium in the dissemination of prospective MAR pathogens to the consumers and thus constitute a potential risk to public health. Significance and Impact of the Study The findings from this study represent the first comprehensive report of Vibrio isolates from ready-to-eat shrimps in Edo and Delta States, Nigeria. Incessant monitoring of Vibrio strains and their predisposition to antimicrobials is a necessity to guarantee seafood safety and guarantee the best treatment regimen for patients with gastroenteritis.