Largest US Measles Outbreak in 30 Years Spreads Florida, New Jersey, North Dakota

The United States and parts of Canada are experiencing significant measles outbreaks in 2025, with the U.S. reporting its largest outbreak in over 30 years, totaling 1,288 confirmed cases as of early July. Florida has confirmed four cases, including two in South Florida, while North Dakota has 35 cases, all involving unvaccinated individuals, and health officials continue to emphasize the critical role of vaccination, particularly the two-dose MMR vaccine which is 97% effective. New Jersey and Ohio have reported potential measles exposures, prompting medical offices to take precautionary measures while awaiting test results. In Canada, New Brunswick confirmed its first case of the year, with officials warning of additional likely cases amid suboptimal vaccination rates in several provinces. Health authorities in all affected areas are urging increased vaccination efforts and caution due to the highly contagious nature of measles, especially with increased summer travel. The outbreaks highlight ongoing challenges related to vaccine hesitancy and the importance of maintaining high immunization coverage to prevent further spread.