MI Flu Cases Rising As New Variant Spreads

Michigan health officials warned Tuesday that flu cases are rising across the state. The warning comes just as holiday travel and activities begin.

State data shows as of the week ending Nov. 22, there were 55 hospital admissions for the flu, a significant increase from just seven at the start of the month.

State health officials are also worried about a new flu variant called subclade K, which they believe is driving up cases across the nation and other countries, including the U.K. and Canada. Positive flu tests reached 13.3 percent the week of Nov. 9, which is higher than the roughly 4 percent it was at this time in 2024, they said.

State health officials said the flu vaccine remains the most effective way to avoid serious influenza illness, preventing 70 to 75 percent of flu-related hospital visits for children and 30-40 percent for adults. They also said tests show it's effective against the new variant.

"The flu vaccine may not prevent mild illness, but data shows it reduces severe complications of influenza, including hospitalization," Michigan’s Chief Medical Executive Natasha Bagdasarian said. "Getting a flu vaccine now is a great way to boost your immunity against influenza through the winter months, when we tend to see even more cases."

So far this season, just 20 percent of Michiganders have received the flu vaccine, raising serious concerns about the potential for high levels of illness, emergency department visits and hospitalizations, especially with the new influenza strain spreading quickly, according to state data.

The flu hit Michigan hard last season. Between October 2024 and May 2025, there were more than 33,000 hospitalizations, with weekly hospitalizations peaking at more than 3,100 in February, according to state data.

Emergency departments saw nearly 8,600 influenza-related visits at the height of the season, almost double from the previous year, health officials said.

There were also 14 pediatric influenza deaths during last season, the highest number recorded since the state began tracking pediatric flu deaths in 2004. That number jumped from eight deaths in each of the previous two seasons, according to state data.

Health officials continue to stress the basics to protect yourself against the flu:

• Get a flu shot (anyone 6 months and older)
• Stay home when sick
• Properly covering coughs and sneezes
• Washing hands frequently and improving indoor ventilation

For more information about statewide influenza trends, vaccine coverage and how to stay protected throughout the season, visit Michigan.gov/COVIDFLURSV.