Comparative severity of COVID-19 cases caused by Alpha, Delta or Omicron SARS-CoV-2 variants and its association with vaccination Elena Varea-Jiménez; Esteban Aznar Cano; Lorena Vega-Piris; Elena Vanessa Martínez Sánchez; Clara Mazagatos; Lucía García San Miguel Rodríguez-Alarcón; Inmaculada Casas; María José Sierra Moros; Maria Iglesias-Caballero; Sonia Vazquez-Morón; Amparo Larrauri; Susana Monge;

Influence of the COVID-19 pandemic on the epidemiology of acute bronchiolitis Lorena Bermúdez Barrezueta; María Gutiérrez Zamorano; Pablo López-Casillas; Marta Brezmes-Raposo; Irene Sanz Fernández; María de la Asunción Pino Vázquez;

Acute bronchiolitis during the COVID-19 pandemic Patricia Flores-Pérez; Nathalia Gerig; Mª Isabel Cabrera-López; José L. de Unzueta-Roch; Teresa del Rosal; Cristina Calvo;