Minnesota has confirmed its first measles case since April, a development that is prompting contact tracing and a special vaccination clinic in the southeastern part of the state.

The Minnesota Department of Health laboratory confirmed the infection in an unvaccinated adult from Fillmore County, according to a county notice. The county said the case was domestically transmitted and was added to state statistics on Sept. 16. County and state public-health workers are identifying people who may have been exposed and checking for additional illnesses.

The infection is Minnesota's 18th measles case of 2026 and the first reported since April, according to MPR News. State health officials told the outlet that the adult had traveled across state lines, but the case appeared unrelated to the outbreak in neighboring Wisconsin. Those details make the investigation important beyond the individual patient: officials must establish where exposure occurred and whether the virus reached other susceptible people.

Measles often begins with high fever, cough, runny nose and red or watery eyes before a rash appears. The CDC says symptoms generally begin seven to 14 days after contact, and complications can include pneumonia and brain swelling. About one in five unvaccinated people in the United States who contract measles requires hospitalization.

The virus spreads through the air when an infected person breathes, coughs or sneezes. It can remain in an indoor airspace for as long as two hours after that person leaves, and an infected person can spread it from four days before through four days after the rash appears, the CDC reports. Up to 90% of susceptible people close to an infected person can become infected.

Fillmore County advises anyone with possible symptoms to remain home and call a medical provider before arriving, allowing the clinic to protect other patients. Residents may also call Fillmore County Public Health at 507-765-2642. People with private insurance should contact their regular provider about vaccination; those who are uninsured, underinsured or enrolled in a Minnesota Health Care Program may contact the county.

The county will hold a vaccine clinic from 4 to 6 p.m. Thursday, Sept. 24, in Room 108 on the lower level of the Fillmore County Office Building, 902 Houston St. NW in Preston. The clinic is open to uninsured and underinsured people ages 6 months and older. The fee is $5, with no charge for people covered by a Minnesota Health Care Program.

Because of the local case, the county has authorized measles, mumps and rubella vaccination for infants ages 6 through 12 months at the clinic. Pregnant patients are not eligible for the live vaccine, and staff will screen attendees for symptoms. The county says one MMR dose is about 93% effective against measles and two doses are about 97% effective. Federal safety guidance says most side effects are mild, while serious reactions are rare.

For families outside Fillmore County, the immediate practical step is to review vaccination records and contact a provider or local public-health agency if a dose is missing. Anyone who may have been exposed should call ahead before seeking in-person care.