In a 2-year-long active surveillance conducted in all German pediatric hospitals, the incidence of hospitalization because of herpes zoster and the clinical picture of complications in children were assessed. Herpes zoster resulted in hospitalization of 244 children, 78 of whom were considered to be immunocompromised. Zoster ophthalmicus (n ؍ 29), meningoencephalitis (n ؍ 22), and zoster oticus (n ؍ 23) (11 cases had Ramsay Hunt syndrome) accounted for 59% of all complications (n ؍ 115). The incidence of hospitalization suggests that at least 1 in every 100 children with herpes zoster is hospitalized and that at least 1 in every 250 immunocompetent children with herpes zoster is hospitalized with complications.Herpes zoster (HZ) results from reactivation of latent varicellazoster virus infection that has been acquired with chickenpox. Although HZ may account for relevant morbidity in adults [1], which is related primarily to postherpetic neuralgia and ophthalmic zoster, HZ in children is believed to be benign unless the child is immunocompromised [2]. We performed a populationbased study to assess the incidence of hospitalization due to HZ, to assess the relative proportions of healthy and immunocompromised children who were hospitalized, and to describe the clinical features of associated complications.Methods and subjects. Active surveillance for HZ in children Ͻ17 years of age who were admitted to hospitals for treatment of HZ was conducted during the 2-year period of January 2003 through December 2004; the surveillance included all German pediatric hospitals. Information on each child was ascertained via a detailed questionnaire.A case of HZ was defined as either hospitalization because of HZ or hospitalization because of any other reason if, 6 days after admission, HZ was identified as the underlying cause. Cases of HZ that erupted while a child was hospitalized for other reasons were excluded. Complications were reported in the following categories: skin infection, ophthalmic zoster, zoster oticus, generalized zoster, and other complications. If meningitis or encephalitis was reported, the diagnosis was summarized as "meningoencephalitis." Children were considered to be immunocompromised if they either received immunosuppressive therapy or had conditions characterized by immunodeficiency.To assess underreporting, a second source was in place in a defined region-North-Rhine Westphalia (NRW), the most populous federal state of Germany (3,248,227 children 17 of age years during 2003 [http://www.destatis.de]). This second source was based on reports from ϳ10,000 general practitioners and pediatricians in primary care. Because these 2 sources can be assumed to be independent and confined to a closed catchment area, capture-recapture incidence estimation was applied.To compare these estimates with the 10th edition of the International Classification of Diseases (ICD10) inpatient-discharge records of HZ (B01.0 -B01.9) or any diagnostic position, all 68 pediatric hospitals in NRW were requested to provide ...