Varicella in Spain: incidence and hospitalization

Background: Varicella is a disease that nearly 100% of population will suffer during their lifetime. Complications of Varicella are more frequent in adults. The aim of this work is to know the characteristics of varicella concerning to susceptibility, incidence, hospitalisation and mortality. Method: data source: Spanish National Network of Epidemiology Surveillance (RENAVE), Spanish Hospital Discharges Data Base (CMBD), Spanish National Institute of Statistic (INE) and epidemiologic regional surveys. Results: a 27% on varicella under-notification is estimated. At 15 years old, more than 90% of population is immunisated. Hospitalizations are more frequent in older than 14 (14 per 1000). The most common complications are bacterian overinfections in children, and pneumonia in adults. Discussion: the risk of hospitalization is related to the elevation increase of age of suffering the disease. If that risk is diminished with the vaccination, and viral tranmision is not broken, the disease will be more severe and more frequent among adults.