The absence of respiratory syncytial virus (RSV) in the winter of 2020- 2021 has likely resulted in a group of children with no natural immunity to the virus, increasing RSV incidence and out-of-season activity as COVID-19 safety precautions are relaxed or lifted, according to findings published in The Lancet Infectious Diseases. Conall Watson, PhD, and colleagues examined surveillance data on RSV infections from December 29, 2014 through March 13, 2022 among children younger than 5. RSV-related activity decreased for all indicators during winter 2020-2021, with 10,280 fewer laboratory-confirmed cases, 92,530 fewer hospital admissions, 2,924 fewer after-hours general practitioner contacts, and 27,486 fewer ED visits compared with predicted values based on winter seasons before COVID-19. An “unprecedented” summer surge of RSV activity occurred in 2021, including 11,255 extra laboratory confirmed cases, 7,604 additional hospital admissions, and 9,789 more ED visits compared with predicted values. Most indicators were also lower than anticipated in winter 2021-2022, though to a lesser extent than winter 2020-2021.
