Epidemiología de las hospitalizaciones atribuibles a infección por Bordetella pertussis en población general en España (1999-2005)

Abstract

ObjectiveBordetella pertussis infection has high hospitalization and morbidity rates in spite of the high vaccine coverage.The aim of this study was to estimate the rate of hospitalization due to B. pertussis infection in Spain, from 1999 to 2005. Material and methodsA retrospective study was carried out using the National Epidemiologic Surveillance System for hospital data (Minimum Basic Data Set [MBDS]) to obtain information on hospitalization, age, length of hospitalization, mortality, case-fatality rates and associated costs. ResultsDuring the study period, 3727 pertussis hospitalizations were recorded (Spanish Version of the International Classification of Diseases, 9th Revision, Clinical Modification: ICD-9-CM codes 033 y 484.3, any diagnostic position), a global annual hospitalization rate of 1.34 per 100,000 people. 85.6% of hospitalizations occurred in children up to 1 year of age, and 95% in children younger than 5 years of age. The highest hospitalization rate was registered in Ceuta and Melilla. The average length of hospitalization was 8.8±8.3 days. During the 7-year study period, there were 23 deaths, of which 16 (69.6%) occurred in children below 1 year of age. The case-fatality rate was 0.62%. The total mean annual cost to the National Health System was 1,024,794.41 €. ConclusionsThe epidemiological pattern found suggests that there are population groups not protected against pertussis,which results in morbidity, mortality and a substantial use of healthcare resources. Booster doses of the vaccine should be given to protect teenagers and adults, which will indirectly protect susceptible, breast-feeding babies.