• Mirjana Makević Đurić
  • Milivoje Đurić


respiratory syncytial virus, bronchiolitis, epidemiology, COVID-19 pandemic


Introduction. Respiratory syncytial virus (RSV) is the most significant cause of acute respiratory diseases, such as bronchiolitis, in children at the earliest age. The COVID-19 pandemic has significantly changed the epidemiology of other viral respiratory diseases, including RSV infections.

Aim. The aim of our study was to examine whether there was a statistically significant decrease in the number of infants and young children affected by viral bronchiolitis during the COVID-19 pandemic.

Methods. The criteria for participation in this retrospective study included subjects aged 1-24 months who, due to respiratory problems, were examined by the pediatrician in the period from 01.01.2019. until 31.12.2022. We classified the subjects into four groups by calendar year: 2019, 2020, 2021 and 2022, and in each year we separated children with symptoms of bronchiolitis from the total number of children with respiratory problems. The diagnosis of bronchiolitis was made clinically. The obtained data were processed by a computer program for statistical analysis of data (SPSS, version 20), and we used the Chi-square test for the significance level p≤0,001.

Results. The total number of subjects for four years was 3,645, and 687 infants were diagnosed with acute bronchiolitis. According to calendar years, in 2019 there were 214 cases, in 2020 there were 172 cases, in 2021 there were 45 cases, and in 2022 there were 256 cases. Using the Chi-square test for the level of significance p≤0,001, we compared the distribution of bronchiolitis patients in the investigated calendar years and found that during the year 2021 there was a statistically significant decrease in the number of patients compared to other years.

Conclusion. The COVID-19 pandemic has significantly changed the epidemiology of other viral respiratory diseases, including RSV infections. In the absence of successful and licensed vaccines, the only ways to reduce the number of children with RSV infection are early detection of patients and implementation of general hygiene measures with epidemiological surveillance and this happened during the COVID-19 pandemic.


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