Southwestern Wisconsin is in the midst of a measles outbreak. As of Nov. 11, there have been more than 550 cases recorded and nine people hospitalized.
Last week, health officials announced that an infant in Grant County died of measles. The health department has not released more specific information about the infant’s location or age to protect their family’s privacy.
Health officials and doctors agree that the best way to prevent measles is by receiving two doses of the Measles, Mumps and Rubella (MMR) vaccine, which was released in 1963.
Under normal circumstances, children receive the first dose of the MMR vaccine between the ages of 12 and 15 months. They receive the second dose between four and six years old.
But last week, the Wisconsin Department of Health Services issued guidance that recommended earlier MMR vaccinations for children as young as six months if they are members of a family or community likely to be exposed to measles.
Measles is an incredibly contagious disease: If one person has it, up to nine out of 10 people who come into close contact with that person will become infected if they are not protected, according to the CDC.
Measles can cause a trademark red rash, fever, cough, red and watery eyes or a runny nose. It carries the risk of serious complications, especially for children under five years old. Complications include pneumonia, encephalitis or swelling of the brain and in some cases, death.
In response to the measles outbreak in Wisconsin, The Wisconsin Policy Forum released a report that looked at statewide levels of immunizations for kids in K-12 schools, including all public school districts and some private schools.
Researcher Don Cramer found that 87.4% of students across the state meet minimum immunization requirements — much lower than the benchmark of 95% widely thought to lead to "herd immunity" against contagious diseases.
Milwaukee Public Schools, the largest district in the state, was one of 18 to report that more than 20% of the student population is not meeting minimum immunization requirements. In 2026, 22% of MPS students did not meet those requirements.
Wisconsin's immunization law mandates that children are vaccinated against 10 diseases: Polio, diphtheria, tetanus, pertussis, measles, mumps, rubella, hepatitis B, varicella, and the meningococcal disease, which causes meningitis. But the law allows for families to file exemptions for health reasons, religious reasons or personal conviction reasons.
Not familiar with the vaccination statuses of your household? You can check online here using the Wisconsin Immunization Registry.
Cramer, the researcher behind the report, spoke with WUWM education reporter Katherine Kokal.
Here's their conversation, which has been edited for length and clarity.
Katherine Kokal: The overall immunization rate of 87.4% is quite a bit lower than this benchmark of 95%. What can you tell us about this benchmark and where we fall?
So 95% is a benchmark that the Department of Health Services uses. It's not really a target, but it is the herd immunity amount for measles, the most contagious of the diseases. So I've been using that as a good benchmark myself as I'm going through the research. But even looking historically, when we look back in the 1980s, there was a high point of 97.5% of students meeting all the minimum requirements for vaccinations. That happened back in 1988. So the current rate of 87.4% is significantly lower than that high rate from 40 years ago.
What did you find about the reasons that are driving people's choices to exempt from vaccinations and how that changed over time?
Yeah, so looking at those three waiver categories, when you look at the the health waivers, they've stayed about the same for the last 40 years. So they hover around 0.3 or 0.4% of students. So that's a very small amount. And then the religious waivers, they've increased slightly. They are at about 1.2% of our students in 2026.
The personal conviction waivers, that's where we're seeing the biggest increase over the last four decades. Back in the '90s, they were below 2%. And then slowly they've been creeping up. And in the last five years, they've reached 6.5% finally in 2026. But they've really ramped up in the last five years.
There are many reasons behind the personal conviction waiver, right?
Correct. Even when we talk to health officials, they list various reasons why someone might sign off on a personal conviction waiver. It might actually be masking, like, an access issue. For a family to try to figure out how to get their child vaccinated, to take time off from work, get the child out of school, get them to the doctors, get the doctor's appointment, it might just be easier for some parents to sign off on that personal conviction waiver than it is to actually get the vaccine. So there is some concern that the personal conviction waivers might be masking more issues than just misconceptions about vaccines or misconceptions about the side effects of vaccines. It might also be an access issue.
When a parent or guardian fills out an exemption form, they have to acknowledge that incompletely immunized students may be excluded from school if there's an outbreak of a disease. What does this mean for education as our immunization rates are fluctuating?
That's a really good question because I think it really brings home the point that we haven't seen outbreaks of these diseases in a long time. And I don't think parents and schools are really thinking about what happens if there's an outbreak and how disruptive that will be for a child's education if they can't go to school because they're not fully vaccinated.
I think that just goes along with the idea that so many of us aren't familiar with how serious these diseases are. Also, there's just so many other effects of having outbreaks and having diseases that could really upset our health, but also upset the education of children and just how families operate.
Not familiar with the vaccination statuses of your household? You can check online here using the Wisconsin Immunization Registry.
