Epidemic Investigation of Chandipura Virus Cases in Ahmedabad City, July 2024

Background: Chandipura virus (CHPV) is an emerging rhabdovirus that has caused periodic outbreaks of acute encephalitis among Indian children.In July 2024, clusters of suspected cases were reported from Ahmedabad City, Gujarat.Objectives: To investigate the outbreak, describe the epidemiological profile of suspected CHPV cases, and assess environmental risk factors in the surrounding community.Methods: A cross-sectional field investigation was undertaken by the rapid response team (RRT) of Narendra Modi Medical College.Five hospitalized children fulfilling the Indian Council for Medical Research (ICMR) case definition were sampled and tested at the National Institute of Virology, Pune/Gujarat Biotechnology Research Centre (GBRC), Gandhinagar.A house-to-house survey of children <15 years (n = 60) residing within 50 yards of index households was conducted.Data on socio-demographic profile, clinical presentation, housing condition, and vector-breeding sites were collected.Descriptive statistics and Chi-square test were applied.Results: Two of the five suspected cases (3 males and 2 females) were laboratory-confirmed for CHPV.All confirmed cases were boys (median age 6 years); one died (case-fatality ratio 50%).Predominant symptoms included high-grade fever (100%), seizures (80%), respiratory distress (60%), and altered sensorium (60%).The community survey revealed a mean age of 5.7 3.8 years; male-to-female ratio 1.5:1.No secondary clinical cases were detected (secondary attack rate 0%).Cracks/crevices were significantly more common in kachha houses than in pakka houses ( = 36.0,p < 0.001).Vector-breeding indices did not differ by housing type (p = 0.71). Conclusion:The investigation confirmed focal transmission of CHPV without person-to-person spread.Early recognition, viral testing, and prompt referral are essential to reduce fatality.Strengthening vector control in kachha dwellings and community health education are recommended to prevent future outbreaks.