Key Points

Monitoring of reports of nosocomial COVID-19, e-SIN, France, from March 1, 2020, to April 8, 2022

• 80% of reports received during Wave 5 corresponded to clusters (at least 3 linked cases) vs. 90% previously

• There has been a renewed increase in the median number of cases per episode since the start of Wave 5 26% of healthcare workers were involved in CGs during Wave 5 vs. 39% previously

• The source of the HC is less often a healthcare professional (19%) vs. 28% previously

• The most common transmission hypothesis (55%) remains the failure to identify a case upon admission during Wave 5 vs. 47% previously