Michigan is seeing an above-average spike in influenza hospitalizations despite lagging national data indicating the state was among the five lowest states just last week.

During the second week of December, Corewell Health East identified 760 flu patients, up from 344 such cases during the final week of November. During that time, the inpatient census for flu jumped from 43 patients to 79, according to Dr. Matthew Sims, the hospital’s director of infectious disease.

This week’s flu case count within the Southeast Michigan health system is more than nine times higher than the same week in 2019, and astronomically higher than the three total cases that had been identified by this time in 2018.

“There’s always variation year to year, but this is an extreme variation,” Sims said.

Dr. Paul Entler, a vice president at Sparrow Health System in Lansing, noted a similar drastic increase. Most concerning to him is the number of hospitalizations related to the flu. Sparrow had 38 inpatients with the flu as of Friday, Dec. 16, compared to one this time last year.

“Where other states have already been overwhelmed with flu, we’re starting to see those same trends here in Michigan,” Entler said. “Typically January, February is where we see a lot of the peaks but his is a steep up climb; much, much steeper than if we were to graph previous years, even pre-pandemic.”

Influenza is a contagious respiratory illness caused be viruses that infect the nose, throat, and sometimes lungs. Common symptoms include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches and fatigue.

Flu season in the U.S. can vary, but typically begins to ramp up in October, with the peak of cases somewhere between December and February, according to the U.S. Centers For Disease Control and Prevention. The overall health impact varies from year to year.

This year’s flu season has picked up earlier than usual, with much of the country reporting “high” or “very high” rates of flu-like illness. According to the latest CDC data, published Friday, Dec. 16, only five states had moderate or lower rates. They include Alaska, Delaware, Hawaii, Michigan, and New Hampshire.

But that data could be lagging current reality in Michigan, health systems have indicated. Michigan doesn’t report statewide flu case data like it does for COVID-19, making it difficult to assess the current surge beyond hospitalization data.

As of a week ago, Michigan had 2.8% of its outpatient visits to health systems identified as having influenza-like illness. That rate was up from 2.4% the week before, but still below the national average (7.2%).

Additionally, Wastewater surveillance systems tracking the virus in Ann Arbor, Jackson and Warren all identified increases in influenza in recent weeks, which could be a sign of things to come.

Among Corewell East’s 760 flu patients last week, 681 were seen in the emergency room. There were 362 adults and about 398 pediatric patients. At the same time, the system had 177 cases of respiratory syncytial virus (RSV) – down from 357 two weeks earlier – and 430 cases of COVID-19, which was on par with late November.

One of the biggest concerns for health care providers is the potential for joint surges this winter, resulting in an overwhelmed system. So far COVID-19 has remained steady and RSV looks to be declining, but it’s early in the season.

“We’ve talked about it in prior years, and fortunately it hasn’t emerged in prior years, about this triple-demic. So flu, RSV and COVID all at the same time,” Sims said. “This year, we’re having it.”

Flu activity during the 2020-21 season was the lowest since current reporting began in 1997. About 0.15% of the nearly 1.5 million samples sent to clinical labs to be tested for influenza came back positive, which was down substantially from nearly 17% the year prior.

Last flu season was also among the mildest in recent memory. Health officials credit the back-to-back low seasons to increased nonpharmaceutical interventions – like masking, social distancing and isolation when ill – introduced to slow the spread of coronavirus during the pandemic.

They expected the recent return of influenza after the Southern Hemisphere reported its worst season in at least five years. Making matters worse is the spike follows a recent surge of RSV, which stressed children’s hospitals, and alongside continued COVID-19 infections.

Hospitals have begun reporting shortages of antibiotics like Tamiflu, which is often used to reduce the strength and longevity of the flu. Dr. Entler said there are other medication options, but those could also be squeezed due to a national demand and existing supply chain issues.

While hospitals and their staffs brace for another potentially challenging winter, health officials like Sims and Entler are again asking residents to protect themselves by hand washing, isolating when unwell, and getting vaccinated to reduce the likelihood of severe illness.

The annual flu vaccine is recommended for anyone 6 months or older, and especially for adults 65 and older and people with certain chronic medical conditions.

Flu deaths in adults do not have to be reported to the CDC, so federal health officials can’t say what percentage of deaths are among those who weren’t vaccinated. However, reporting is required for children. Between 2010 and 2020, approximately 80% of flu-related deaths in children occurred in cases where the children were not vaccinated.

To find a vaccine near you, visit vaccines.gov or call the COVID-19 Hotline at 888-535-6136 (press 1) between the hours of 8 a.m. and 5 p.m. Monday through Friday, or 10 a.m. and 2 p.m. on the weekend.

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