Low reactogenicity of the virosomal subunit influenza vaccine in healthy children without risk factors

Abstract

ObjectivesTo estimate the reactogenicity of the inactivated virosomal subunit influenza vaccine in healthy children. Material and methodsDuring the 2004-2005 influenza season we carried out a prospective cohort study in 11 paediatric clinics of the metropolitan region of Barcelona to evaluate the effectiveness, efficiency and reactogenicity of one dose of inactivated virosomal subunit influenza vaccine in healthy children. The vaccine was administered to healthy children aged 3-14 years attended in 5 of the 11 clinics whose parents gave informed consent to participate in the study. These children formed the vaccinated cohort (n=966). The unvaccinated cohort (n=985) was formed by children attended in the other six clinics whose parents agreed to participate. ResultsSeven point five percent of the 966 children vaccinated suffered one or more local or systemic adverse reactions. The most common were local reactions: erythema (4.04%) and induration (1.76%). Systemic reactions were much less frequent, with malaise (0.72%) and fever (0.52%) the most common. ConclusionsThe virosomal influenza vaccine has low levels of reactogenicity and is very well tolerated in healthy children.