The laboratory at Hospital Clínic de Barcelona was the first in Spain to detect a new coronavirus that ultimately caused the worst health crisis in modern times. It was February 25, 2020, as the head of the center's Microbiology Service, Climent Casals, recalls, and the date is etched in memory. The outbreak of COVID-19 paralyzed the world with serious health, economic, and social consequences, but it also had a major impact on the other pathogens that had been circulating in our country until then; it displaced them and practically achieved a monopoly on infections. Five years later, pre-pandemic normality has returned, and the map of bacteria and viruses has also changed. Therefore, professionals insist on the importance of having a surveillance system capable of detecting and anticipating any emergency. so that what happened in 2020 does not happen again.