Impact of the COVID-19 pandemic on infectious disease hospitalizations of neonates at a tertiary academic hospital: a cross-sectional study

Background To investigate the impact of the coronavirus disease 2019 (COVID-19) pandemic on hospitalizations for neonatal infectious diseases. Methods We analyzed data for neonatal inpatients admitted at a tertiary academic hospital with a principal diagnosis of an infectious disease during January 2015 to December 2020. We compared hospitalizations in 2020 (COVID-19 cohort), corresponding with the impact of COVID-19 pandemic and associated containment measures, and the comparable 2015 to 2019 (pre-COVID-19 cohort). Results 14,468 cases admitted for neonatal infectious diseases were included in our study, with 1201 cases in the COVID-19 cohort and 13,267 cases in the pre-COVID-19 cohort. The leading causes of hospitalizations for neonatal infectious diseases remain being respiratory tract infections (median ratio = 0.461, 95% CI 0.335-0.551), sepsis (median ratio = 0.292, 95% CI 0.263-0.361), gastric intestinal infections (median ratio = 0.095, 95% CI 0.078-0.118) and dermatologic infections (median ratio = 0.058, 95% CI 0.047-0.083). The seasonality of neonatal infectious disease hospitalizations could be obviously observed, with the total number and the overall rate of hospitalizations for neonatal infectious diseases in the first and fourth quarters greater than that of hospitalizations for neonatal infectious diseases in the second and third quarters in each year (1362.67 +/- 360.54 vs 1048.67 +/- 279.23, P = 0.001; 8176/20020 vs 6292/19369, P < 0.001, respectively). Both the numbers and the proportions of hospitalizations for neonatal infectious diseases in different quarters of the COVID-19 cohort significantly decreased as compared with those forecasted with the data from the pre-COVID-19 cohort: the numbers per quarter (300.25 +/- 57.33 vs 546.64 +/- 100.43, P-value = 0.006), the first quarter (0.34 vs 0.40, P = 0.002), the second quarter (0.24 vs 0.30, P = 0.001), the third quarter (0.24 vs 0.28, P = 0.024), and the fourth quarter (0.29 vs 0.35, P = 0.003). Conclusions Despite the outbreak of the COVID-19 pandemic, the leading causes of hospitalizations for neonatal infectious diseases remain unchanged. The seasonality of neonatal infectious disease hospitalizations could be obviously observed. The numbers as well as the overall rates of hospitalizations for neonatal infectious diseases in the COVID-19 cohort dramatically declined with the impact of the COVID-19 pandemic and its mitigation measures.