A new measles case in Minnesota, reported just as the recent outbreak seemed to be winding down, has state health officials on alert because it involved a white adult who had visited public places in Hennepin, Ramsey and Carver counties while infectious and who had circulated among several people known to be unvaccinated.

Reported Thursday by the Minnesota Department of Health, the case brings the total for the current measles outbreak to 79. Most of the previous cases involved Somali-American children.

The infected person was "likely exposed to measles at locations frequented by the last identified case" and had not been vaccinated, the Health Department said in a news release. The agency is monitoring unvaccinated people who had been around the infected individual; the patient is recovering and has been asked to stay at home.

While the latest infected person is not related to the prior measles patient, the individual lived in the same area and had frequented the same grocery store and other locations, said Kris Ehresmann, the Health Department's director of infectious diseases. She declined to identify specific locations where transmission might have occurred because she said that would be misleading.

"We can't be sure we've identified all of the locations, and that could give a false sense of security," she said. "If you're someone who's not vaccinated, you're at risk for measles."

Minnesota's largest previous outbreak had been 26 cases in 2011.

The latest outbreak emerged among Somali-American children attending the same child care facilities.

A new case hadn't been reported in weeks, and state officials had hoped they would reach the 42-day window at which they could declare the outbreak over. "We do reset the clock and now we have to go an additional 42 days," Ehresmann said.

Twenty-two of the measles victims in the latest outbreak needed hospital care. None died.

The latest case involved a younger adult who was never vaccinated for the measles due to parental objections. Health officials in Hennepin County interviewed the individual to identify relatives, friends and others who are also unvaccinated and might be at risk.

Roughly 90 percent of Minnesotans are unlikely to get sick from the measles because they were vaccinated as children. Doctors have been alerted to be watchful for the infection, though, and its classic symptoms of cough, runny nose, fever and rash.

Jeremy Olson • 612-673-7744