Comparison of methicillin-resistant Staphylococcus aureus carriage in a neonatal intensive care unit between pre- and post-COVID-19 pandemic periods, following the introduction of strengthened infection control measures: a retrospective study.

BACKGROUND

Infants hospitalized in the neonatal intensive care unit (NICU) often carry methicillin-resistant Staphylococcus aureus (MRSA). During the coronavirus disease 2019 (COVID-19) pandemic, infection control measures were strengthened in the NICU, primarily restrictions on visits and strict infection control measures for visitors. This study investigated the impact of strengthening infection control measures in the NICU during the COVID-19 pandemic on the frequency of MRSA colonization in infants.

METHODS

This retrospective study included 1066 infants hospitalized in our NICU between 2017 and 2022. In response to the spread of COVID-19, the bundle of infection control measures in the NICU was strengthened since March 2020. We compared the MRSA carriage rate between the prepandemic (2017-2019) and postpandemic (2020-2022) periods.

RESULTS

Of the 1066 infants, 578 and 488 were hospitalized in the NICU during the pre- and post-COVID-19 pandemic periods, respectively. There was no significant difference in the proportion of infants with MRSA colonization in the NICU between the pre- and post-COVID-19 pandemic periods (7.8% vs 10.8%). A multivariate logistic regression analysis demonstrated that the post-COVID-19 pandemic period, during which infection control measures were strengthened, was not associated with MRSA carriage rates.

CONCLUSION

The proportion of infants with MRSA colonization in the NICU did not decrease during the post-COVID-19 pandemic period despite strengthened infection control measures. The transition to a stricter infection control bundle, including infection control measures for visitors, may not be the main factor contributing to a decrease in the frequency of MRSA carriage in the NICU setting.