Public Health Agency of Catalonia, Sub Directorate of Surveillance and Response to Public Health Emergencies, Roc Boronat 81-95, 08005 Barcelona, Spain.
CIBER Epidemiology and Pubic Health CIBERESP, Instituto Carlos III, Av. Monforte de Lemos, 3-5, Pabellón 11, 28029 Madrid, Spain.