On March 31, 2025, the Centers for Disease Control and Prevention (CDC) ordered staff not to release an expert assessment showing an increased risk of contracting measles in areas with lower vaccination rates. The analysis was also expected to emphasize the importance of vaccination as a preventive measure against the highly contagious virus.
A CDC spokesperson said that the agency did not release the assessment “because it does not say anything that the public doesn’t already know.” She also stated that the CDC continues to recommend vaccination against measles, adding that “[t]he decision to vaccinate is a personal one” that people should discuss with their medical providers in order to “be informed about the potential risks and benefits associated with vaccines.”
Jennifer Nuzzo, the director of the Pandemic Center at Brown University School of Public Health, called the shift in messaging and the cancellation of the assessment “alarming,” saying “I’m a bit stunned by that language… [which] makes it sound like it’s a very active coin toss of a decision.”
The risk assessment was compiled by the CDC Center for Forecasting and Outbreak Analytics, which uses data and expertise to predict the course of disease outbreaks.