Federico Martinón-Torres1. 1. Translational Pediatrics and Infectious Diseases Section, Pediatrics Department, Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, Spain; Genetics, Vaccines, Infections, and Pediatrics Research Group (GENVIP), Healthcare Research Institute of Santiago de Compostela, Santiago de Compostela, 15706, Spain. Electronic address: federico.martinon.torres@sergas.es.