Tens of thousands of students will be returning to Wisconsin schools without being vaccinated against measles.
State officials say that nearly 50,000 children have vaccination waivers, allowing them to attend school without getting all their shots.
So far this year, there have been over 1,200 cases of measles across the country.
Although none of those cases were recorded in Wisconsin, health officials are sounding the alarm.
The most recent data shows that most counties in Wisconsin have twice the amount of unvaccinated people necessary to spread the disease.