Wisconsin Baby Dies of Measles in First State Death in 36 Years

(Bloomberg) — Wisconsin reported its first measles death in more than three decades on Thursday, the latest state to suffer a fatality from a virus that was long eradicated in the US but recently surged back amid a wave of anti-vaccine sentiment.

The death occurred in an infant, the Wisconsin Department of Health Services said in a statement. It is the third US measles death within the last week — matching the number of deaths in all of 2025. In the preceding 25 years, the US typically had no deaths.

Across the US, measles has been spreading at an increasing rate as vaccination uptake has declined. That’s eroded the herd immunity that protects people who cannot be vaccinated like infants and the immunocompromised. At least 45 states have reported infections for a total of 4,852 people, according to the Centers for Disease Control and Prevention. 

The highly contagious virus has been spreading in the southwestern part of Wisconsin and nine people have been hospitalized in connection with the outbreak, according to the health department.

“Any death of a child is a tragedy and even more so when it is related to a vaccine-preventable disease,” Wisconsin State Health Secretary Kirsten Johnson said in a statement. 

With the US measles case count at its highest in decades, its long-held status as a measles eliminated country is under threat. An outside group of experts is scheduled to meet next week and review the data to determine whether the US has seen continued transmission of the disease for more than 12 months. 

This week, Pennsylvania confirmed a sixth death from measles and New York reported its first. Utah, South Carolina and Texas have also seen particularly bad flareups of measles over the last year.

Wisconsin said local healthcare providers and public health staff have delivered more than 42,000 doses of the measles, mumps and rubella vaccine since August. No vaccine is perfect, but the MMR is 97% effective after two doses. 

One to three people out of 1,000 are likely to die from measles, according to the CDC. The respiratory infection can cause flu-like symptoms and a distinct red rash across the body. Complications include brain swelling, pneumonia and death. 

The CDC has confirmed only four of the deaths this year. After Pennsylvania reported its first fatalities, Health and Human Services Secretary Robert F. Kennedy Jr. suggested the state’s governor Josh Shapiro may have fabricated them for political gain — sparking a verbal dispute. The CDC is working on a national measles death definition with an outside group of epidemiologists.

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