Concurrent Multiple Outbreaks of Varicella, Rubeola, German Measles in Unvaccinated Children of Co-Educational Mount Carmel Senior Secondary School, Thakurdwara Palampur of Northern Himachal, India

BACKGROUND: In April, 2009, in a co-education school, we investigated suspected triple outbreak; varicella first and then with chance detection of rubeola and rubella. The aim was to confirm diagnosis and recommend remedial measures to prevent further outbreaks. MATERIALS AND METHODS: We defined a case of varicella with maculopapulovesicular rash without other apparent cause in students or staff of the school and residents of neighboring villages of Khalet and Roady since 23(rd) March to 14(th) October, 2009. We line listed case patients and collected information on age, sex, residence, date of onset, symptoms, signs, traveling, treatment history, and vaccination status. The outbreak was described by time, place, and person characteristics. Diagnosis was confirmed epidemiologically and serologically; first to chickenpox, measles, and german measles viruses. RESULTS: We identified 505 case patients from mixed outbreaks of varicella, measles, and german measles (30/505 clinically, 467/505 epidemiologically linked and 8/505 laboratory confirmed case patients from a study population of 3280. We investigated the suspected outbreak with case definition of varicella but measles 20/3280 (0.60%) and rubella 34/3280 (1.03%) cases were also observed. The overall attack rate (AR) was 15% while in school; it was 22% but highest (56%) in Nursery up to 4(th) standard with index case in first standard. Sex-specific AR was (23%) more in boys. Triple concurrent infection caused 05% complications but no death was reported. Severity of the symptoms was more in 5(th) standard onwards with 49–249 lesions and severer in poor villages Roady and Khalet (P < 0.05). Only 4% were immunized against varicella/german measles privately. Seventeen percent of the cases went for traditional treatment vs modern medicine (P < 0.001). 5/10 samples for IgM antibodies for chickenpox and 2/10 samples were positive for rubella. CONCLUSIONS: Triple infection of varicella, measles, and rubella was confirmed epidemiologically and serologically. We recommended local authorities for MMRV in the school and near villages with aggressive IEC activities in affected areas.