Introduction : Contaminated food sickens one in ten people globally every year. In Kodaikanal, Tamil Nadu, India, On 12th November, 2024 an acute gastro-enteritis outbreak occurred among school students who came for excursion from Kerala. Food borne outbreaks commonly occur due to poor hygiene or handling practices. The objective is to analyse patterns, to pinpoint the source (food or environmental) and symptoms, thereby providing insight for prevention strategies.
Methods : As modified the case definition as; Any case with one episode of diarrhoea with or without vomiting and fever and not Integrated disease surveillance programmes standard case definition. Interviews were conducted, line listed with demographic and clinical symptom (person). An epi-curve (time) and spot map (place) aided in understanding the outbreak's temporal and geographical distribution. Attack rates were calculated. Stool, blood & water samples were collected. A retrospective cohort study analysed food exposures, while risk ratios were computed using epi-info software. RESULTS: Among the 187 (184 were students and 3 were teachers) consumed steamed biriyani, Chicken curry, Rice, Parotta, Gobi 65, Chapatti and Vegetable curry for dinner. There were 109 cases, with vomiting (47%) and diarrhoea (14%) with fever (11%). The median incubation period was 6 hours and 45 minutes. Microbiology results for stool and blood samples were inconclusive, as were the water samples; We found an association between symptoms and food consumption. A retrospective cohort study indicated a risk ratio of 1.36 (95% CI: 1.10 – 1.84) for chicken curry, attributing 80% of cases to it.
CONCLUSION: The acute gastroenteritis outbreak was a single-exposure, point-source event with rapid symptom onset following the consumption of chicken curry; despite inconclusive laboratory and water sample results.