Investigation of a cluster of acute-onset seizures and deaths among children, Sirohi District, Rajasthan, April 2022

Abstract

Background: Following reports of seven deaths among children with seizure and vomiting in the village of Sirohi, Rajasthan in April 2022, an epidemiological investigation was conducted.  Methods: We established a hospital-based surveillance and did active case finding. A case was defined as vomiting and acute onset seizure or altered sensorium in <18 years old in Verafalli village. We conducted verbal autopsy and collected information on food, behaviours and health-seeking. Food samples, cerebrospinal fluid (CSF) and blood specimens were collected for testing biochemical, bacterial and viral markers. Environmental surveys were conducted around cases’ houses for presence of poisonous vegetation and potential vectors.  Results: Among 11 cases (median age 7 years (2-16 years), females 27%), all had vomiting, new-onset seizure was present in 73% and altered sensorium in 27%; 33% were hospitalized. Case fatality was 64%. No new cases were identified after April 2022. Median time between symptom onset and death was 9 hours (2-54 hours). Among deaths 28% (2/7) were hospitalized. Two deaths had low weight-for-age, blood glucose <25 mg/dl (refractory hypoglycemia) and elevated liver enzymes (SGPT >8000 IU/L). Lab results for food and CSF samples were inconclusive for bacterial and viral markers. Toxicology screen of one death was negative for organophosphates. In 25% (2/8), tick pools tested positive for rickettsia. All cases had houses in vicinity or within fennel crop area.  Conclusions: This acute health event cluster presenting as acute seizures with rapid progression among children in a rural setting was likely due to environmental toxin consumption; high fatality may result from uncorrected metabolic derangement. Aflatoxin is commonly known to infect fennel crops. We recommend early identification and case management to prioritize metabolic derangement correction; continued surveillance and a systematic epidemiological investigation to evaluate the role of environmental toxins particularly aflatoxin as the underlying etiology for similar events in future.