Minnesota health officials warned the public after an unvaccinated child with measles visited the Mall of America’s theme park on May 24 from 5–9 p.m. “Thousands may have been exposed,” as measles spreads easily through the air and can linger for hours. Jessica Hancock-Allen called it “worrying” that the infection source is unknown, indicating possible community spread.

Officials urge exposed individuals to monitor symptoms until June 14, especially the unvaccinated, who face the greatest risk. Two more cases were confirmed in early June, raising the state’s 2025 total to four. Nationwide, the U.S. has seen 1,168 measles cases this year—quadruple last year’s—with three deaths reported, all among unvaccinated individuals.

Vaccination rates have dropped since the pandemic. Minnesota’s MMR rate fell from 92% in 2019 to 87% in 2024, below the 95% needed for herd immunity. “Even small additional declines…could make measles endemic,” warn Stanford researchers.

Measles causes high fever, rash, cough, and can lead to pneumonia, brain damage, or death. Infants, pregnant women, and immunocompromised individuals are most vulnerable.

The MMR vaccine is 97% effective with two doses. Officials stress that boosting vaccination rates and fighting misinformation is key to preventing future outbreaks.