Foodborne Outbreak by Serovar Weltevreden in West Bengal, India.

Foodborne gastroenteritis outbreaks owing to serovar Weltevreden ( Weltevreden) represent a significant global public health problem. In the past two decades, Weltevreden has emerged as a dominant foodborne pathogen, especially in South-East Asian countries. This report describes a community foodborne outbreak of gastroenteritis caused by Weltevreden in August 2022 following consumption of panipuri from a street vendor in the Polba block in Hooghly district, West Bengal, India. This food item was consumed by 185 people, of whom 129 had acute watery diarrhea with other clinical symptoms and 65 of them were admitted to different District hospitals for treatment. Stool specimens collected from hospitalized cases were positive for , and further serotyped as Weltevreden. All the Weltevreden strains possessed the pathogenicity islands associated genes (, , , , , , , the enterotoxin (), and hyperinvasive locus gene (). Except erythromycin, all the strains were susceptible for commonly used antimicrobials in the treatment of diarrhea. The I-based pulsed-field gel electrophoresis analysis indicated that all the isolates responsible for the recent outbreak were similar, but diverged from other Weltevreden that were previously reported in West Bengal. This report indicates that foodborne infection is a major public health concern in India and demands to strengthen capacity-building measures at the local health care levels for linking causative agents of outbreaks.