Description of influenza B in seasonal epidemic in cantabria during the beginning of the pandemia due to SARS-CoV-2

Abstract

Introduction. Co-circulation of the two Influenza B lineages hinders forecast of strain to include in trivalent vaccine. Autonomous Communities such as Cantabria continue with-out supplying tetravalent vaccine. The aim of this study was to analyse epidemiological characteristics of influenza type B in Cantabria (2019-2020 season) as well as to establish the pre-dominant lineage and its relation to the recommended vac-cine. Methods. Retrospective study whereby flu diagnosis and lineage analysis were determined by RT-PCR. Results. All samples belonged to the Victoria lineage. Most prevalent viral co-infection was due to SARS-CoV-2. The population affected by influenza B was mainly paediatric and non-vaccinated patients more frequently required hospital ad-mittance. Conclusions. Influenza type B has a higher incidence in the paediatric population and type A affects more the adult population. Only 28.8% of patients with Influenza B that pre-sented with some underlying condition or risk factor were vaccinated. This shows the need to increase coverage with tetravalent vaccines in order to reduce the burden of disease associated with the Influenza B virus.