In a photo from Thursday, Feb. 4, 2021, provided by the Michigan Office of the Governor, Elizabeth Hertel, director of the state health department addresses the state. (Michigan Office of the Governor via AP)

LANSING, Mich. (AP) — Michigan, where COVID-19 is surging more than in any state, on Thursday reported its first confirmed case of a coronavirus variant that was initially identified in Brazil.

There are concerns it might affect re-infect people who have already had COVID-19. The variant was found in a resident in Bay County, where the local health officials were investigating the person’s exposure history.

State Health and Human Services Director Elizabeth Hertel expressed concern. Michigan has the second-most cases of another variant — first identified in the U.K. — that is more contagious than the original strain that drove the U.S. outbreak last year.

“It is now even more important that Michiganders continue to do what works to slow the spread of the virus by wearing their masks properly, socially distancing, avoiding crowds, washing their hands often and making a plan to get the safe and effective COVID-19 vaccine once it is their turn,” she said in a statement.

As of Thursday, the state had the country’s highest new case rate in the past week, according to the Centers for Disease Control and Prevention. It added 6,000 cases for the second day in a row.

The seven-day average, 5,061, has grown six-fold over nearly six weeks. It is below the 6,825 average from mid-November, when the state closed high schools to in-person instruction, stopped organized sports, prohibited indoor restaurant dining and closed various entertainment businesses such as movie theaters and bowling alleys. On Thursday, hospitals had about 2,500 adult patients with confirmed cases. That number stood at roughly 3,100 when Democratic Gov. Gretchen Whitmer announced the restrictions more than four months ago.

The seven-day daily average of deaths, 22, is well below past peaks.

Whitmer has said variants are a factor in the state’s spiking cases and hospitalizations. She does not want to tighten restrictions that her administration gradually loosened in recent months. But the rising case rate and hospitalization totals are similar to what they were less than a week before the last restrictions were ordered.

A mask requirement remains in effect, unlike in several states with Republican governors. Starting Friday, Michigan will require teen athletes to undergo regular coronavirus testing. The governor has been emphasizing vaccinations.

More than a third of people in Michigan ages 16 and older have received at least one shot.

Dr. Adnan Munkarah, executive vice president and chief clinical officer at Henry Ford Health System, said this week that patients with COVID-19 are younger, showing that vaccinating seniors has worked.

“This is why we believe that we have a way out of this,” he said. “Please continue to keep your guard up.”