Chickenpox in Poland in 2024

Background Chickenpox (Varicella) is a highly contagious viral disease caused by the Varicella-zoster virus (VZV), a member of the Herpesviridae family. While it most commonly affects children and typically follows a mild course, it can lead to severe complications in infants, pregnant women adults, and individuals with immune deficiencies. Following the initial infection, the virus remains latent and may reactivate later in the form of shingles (herpes zoster). Infection during pregnancy or the perinatal period poses a particular risk. Objective The objective of this study is to assess the epidemiological situation of chickenpox in Poland in 2024, in comparison to previous years. Material and methods The assessment of the epidemiological situation of chickenpox in Poland is based on data submitted to the National Institute of Public Health NIH – National Research Institute (NIPH NIH – NRI) by District Sanitary-Epidemiological Stations. These data are published in the annual bulletin "Infectious Diseases and Poisonings in Poland in 2024", alongside information from the annual bulletin "Vaccinations in Poland in 2024". Results In 2024, 153,719 cases of chickenpox (varicella) were registered in Poland (409.2 per 100,000 population), representing a 19.45% decrease compared to 2023 and a return of the incidence rate to a level similar to the median for the years 2018-2022. A total of 912 patients (0.59% of cases) required hospitalisation. The highest incidence rates were recorded in the Śląskie and Pomorskie voivodeships, as well as among children under 9 years of age – most notably among 4-year-olds. In 2024, 79,122 vaccinations against chickenpox were administered, 99.2% of which were given to individuals under 19 years of age. Conclusions In 2024, the incidence of chickenpox in Poland was 409.2 cases per 100,000 population, a level comparable to the median for the 2018-2022 period. These findings underscore the importance of early vaccination and maintaining high vaccination coverage, especially within at-risk groups.