Summary -- What is already known about this topic? - Parvovirus B19 (B19) is a respiratory virus that can cause adverse fetal outcomes in pregnant women and persons who are immunocompromised or have chronic hemolytic blood disorders . After relatively low rates during the COVID-19 pandemic years of 2021–2023, B19 activity in 2024 exceeded that of prepandemic years. -- What is added by this report? - Data from the National Syndromic Surveillance Program indicated that the proportion of sera specimens positive for B19 antibodies during January–May 10, 2025, was higher than during the same period in 2024 , suggesting a sustained increase in B19 transmission. -- What are the implications for public health practice? - Health care providers should have a heightened suspicion of and consider providing testing for B19 infection among groups at high risk for severe outcomes, including pregnant women with compatible symptoms or exposure to B19. Among pregnant women, health care providers should ...
Media Monitoring for Signals about Emerging Threats