health
US measles outbreaks spread across counties as vaccination patterns shift, preprint finds
An analysis of US county data from 2011 to 2025 found that measles outbreaks have become more closely associated with local vaccination coverage and have spread more often across county borders. A spatial model identified counties at higher risk, and projected that a five-percentage-point coverage increase in the highest-risk counties could reduce long-term national measles risk by more than 90%.