EP04.05: Impact of the COVID‐19 pandemic on parvovirus B19 infection rates in pregnancy: is there a post‐pandemic epidemic?

Public health measures during the COVID-19 pandemic affected the incidence of various viral infections, including parvovirus B19. Notably, parvovirus B19 infections can cause serious complications in pregnancy such as fetal anemia. Due to low viral infection rates during the pandemic, this study assumes a rise of parvovirus B19 infection numbers after the pandemic and associated hygienic measures. This was a retrospective cohort-study analysing the prevalence of parvovirus B19 among pregnant women who had PCR testing due to suspicion of parvovirus infection at the Department of Obstetrics and Fetomaternal Medicine at the Medical University of Vienna, Austria from January 2013 to September 2023. Study groups were defined in concordance with Austrian public health measures: a pre-pandemic group (January 2013 to February 2020), a pandemic group (March 2020 to April 2023) and a post-pandemic group (May 2023 to September 2023). During the study period, a total of 256 pregnant women who had PCR testing for parvovirus B19 were identified, comprising 27 women with a positive test result. The annual number of cases ranged from 0 to 11 infections per year. In the pre-pandemic group (n = 149) 14 women had a positive test result, in the pandemic group (n = 87) 3 women tested positive and in the post-pandemic group (n = 20) 10 women tested positive. The overall prevalence for parvovirus B19 was 0.11, annually ranging from 0.00 in 2021 to 0.46 in 2023. Considering the predefined study groups, the highest prevalence was demonstrated in the post-pandemic group (0.50), whereas the lowest prevalence was shown in the pandemic group (0.04). In the pre-pandemic group the prevalence was 0.09. Prevalence of the predefined study groups differed significantly (p ≤ 0.001). This study indicates a significant rise of parvovirus infections among pregnant women after the COVID-19 pandemic suggesting an impact of public health measures on parvovirus B19 infection rates.