Objective: To describe pre-COVID-19 pandemic current practices in virological investigations, including type, frequency of samplings, and documented viruses, in sudden unexpected death in infancy (SUDI) and to compare results according to the cause of death.
Study Design: Between May 2015 and December 2019, infants under 2 years of age included in the French SUDI registry were classified in one of 4 groups by causes of death according to the classification by Goldstein et al. : unexplained (SIDS), infectious, explained but noninfectious, and undetermined.