Analysis of COVID-19 nosocomial clusters in an Omicron strain epidemic: importance of patient education on infection control measures.

A cluster of 129 patients with coronavirus disease 2019 (COVID-19) nosocomial infections was analysed during the Omicron strain epidemic. The incubation period for nosocomial Omicron strain infections was found to be 3 days. The transmission route of the first patient with COVID-19 (FCP) in each room is a critical factor within these clusters. There have been few cases of healthcare-worker-to-patient transmission, and most FCPs maintained high levels of activity in daily living. The primary routes of nosocomial infection among FCPs likely involved patient visits or direct conversations between patients. Therefore, hospital clusters can potentially be mitigated by educating patients on infection control measures, such as proper mask-waring and hand hygiene.