Characteristics of rotavirus infections in the region of Silesia between June 2019 and August 2022, in terms of mandatory vaccination

Introduction
The aim of this study was to evaluate the impact of mandatory rotavirus vaccination introduced in 2021 and COVID-19 pandemic-related restrictions on the incidence, severity, and clinical characteristics of rotavirus-induced acute gastroenteritis in children hospitalised at the Department of Paediatrics, Medical University of Silesia, between June 2019 and October 2022.

Material and methods
A total of 324 paediatric patients diagnosed with rotavirus infection were included in the analysis. The study compared clinical data before and after the introduction of mandatory vaccination in 2021 in children aged under 6 months and during the COVID-19 pandemic.

Results
The results indicated a significant decrease in non-vaccinated hospitalisations (non-vaccinated/vaccinated patients) from 98.77% before to 79.84% after the introduction of mandatory vaccination. Post-vaccination, the average age of hospitalised patients increased significantly (mean age: 3 years 7 months, compared to the period before vaccination introduction mean age: 1 year 7 months) and the length of hospital stay was reduced. The study also observed a seasonal peak in rotavirus infections from December 2021 to March 2022, contrasting with the absence of seasonality in previous years, likely due to COVID-19 restrictions. Laboratory findings showed no significant differences in blood pH, C-reactive protein, and alanine aminotransferase levels between the pre- and post-vaccination periods, but there was a significant reduction in base excess, suggesting a milder disease course after vaccination.

Conclusions
Mandatory rotavirus vaccination and pandemic restrictions are also known to greatly mitigate the severity of the disease and reduce hospital stay in children. Not only do these measures reduce the incidence of severe rotavirus infection in young patients, but they also decrease the economic burden on healthcare systems and alleviate the suffering of young patients. This leads to health benefits for children as well as the reduction in hospitalisation costs. As a result, children’s overall well-being is improved and healthcare resources are more effectively allocated.