Epidemiology of hospital admissions for paediatric varicella infections: a one-year prospective survey in the pre-vaccine era.

To evaluate the epidemiology of hospital admissions for varicella in children, a 1-year prospective multicentre study was done in Northern France in the pre-varicella vaccine era. The 405 children aged <16 years seen at local hospitals for varicella or herpes zoster were included. Among them, 143 who had varicella and resided in the district were admitted. Admission incidence rates were 28/100000 children aged <16 years (149/100000 infants aged <1 year, 69/100000 children aged 1-4 years, and 2/100000 children aged 5-15 years). Most admissions (57%) were related to complications, usually skin infection (47%). Independent risk factors for admission were place of residence outside the district [adjusted odds ratio (aOR) 8.7], complication at admission (aOR 5.8), recurrent fever (aOR 4.5), recent varicella in a sibling (aOR 4.0), and previous physician visit for the same condition (aOR 2.0).