ObjectiveTo clarify the infection control measures required in the event of a new infectious disease outbreak, we conducted a questionnaire survey on the infection control measures implemented against coronavirus disease 2019 (COVID-19). MethodsAn invitation to participate in this survey was sent to the heads of 2689 facilities affiliated with the members of the Japanese Society for Infection Prevention and Control in February 2023, requesting responses to the online survey using Google Forms by March 2023. ResultsSix hundred and forty-five facilities, including 20 clinics and 625 hospitals, participated in the survey. This survey revealed that various infection control measures were implemented, including universal masking in the non-COVID-19 ward (96.5 %), screening tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on scheduled admission (89.0 %), SARS-CoV-2 tests (98.7 %), and isolation in private rooms (76.5 %) for inpatients with fever. However, nosocomial infections and clusters of COVID-19 occurred in 94.4 % and 90.9 % of cases during the investigation period, respectively. One of the reasons for these results is that healthcare personnel (HCP) and patients were common index cases of nosocomial infections, and the most common cause of clusters was the work of symptomatic HCPs. These results suggest that HCPs should understand that they can be index cases or spreaders. On the other hand, the most common support from external facilities was healthcare centers, followed by physicians or nurses from other hospitals. ConclusionIn response to the emergence of infections, it is important to consider implementing infection control measures for HCPs and patients.