Michigan is currently dealing with a surge in influenza B, elevated stomach illness activity, and ongoing COVID-19 circulation. Flu-like illness visits across the state sit at 5.0% and are trending upward, with influenza B reaching “very high” levels in several regions. Norovirus cases in 2025 hit their highest total in at least five years.
Influenza B Is Driving the Current Flu Surge
While influenza A tends to dominate early flu season headlines, influenza B is the bigger concern in Michigan right now. The Southwest region is reporting high to very high influenza B activity, and the Central region is seeing moderate to very high levels. Even the Southeast region, which includes the Detroit metro area, has influenza B classified as “low to elevated” and climbing.
Influenza A, by contrast, is holding steady or declining in most parts of the state. The Central region shows moderate but decreasing influenza A activity, and the Southwest region’s elevated levels are also trending down. The North region remains low for both strains, though both are ticking upward.
Influenza B often hits later in the season and tends to cause more severe illness in children than influenza A. Symptoms are the same as any flu: fever, body aches, chills, cough, and fatigue. If you’re feeling run down with a sudden onset of these symptoms, flu is a strong possibility right now, especially if you’re in the western or central parts of the state.
Norovirus and Stomach Bugs at Record Levels
Michigan reported 2,953 confirmed norovirus cases in 2025, nearly double the previous year’s total of 1,508 and the highest count in at least five years. That’s a significant jump from 2023 (869 cases) and 2021 (592 cases). The spike isn’t just a Michigan story, as norovirus has been surging nationally, but the state’s numbers reflect a clear escalation.
Broader gastrointestinal illness reports tell a similar story. During the week ending December 20, 2025, Michigan logged over 5,000 gastrointestinal illness cases in a single week. That weekly peak dropped off heading into the holidays, but the year-end total of nearly 145,000 cases was the highest on record for the state over the past five years.
Norovirus spreads fast in close quarters: schools, daycares, nursing homes, restaurants. It causes sudden vomiting, diarrhea, and stomach cramps, and it typically lasts one to three days. The virus is notoriously hard to kill on surfaces. Alcohol-based hand sanitizer doesn’t work well against it. Soap and water is your best defense, along with thorough cleaning of any contaminated surfaces with bleach-based products.
COVID-19 Still Circulating
COVID-19 hasn’t disappeared from Michigan’s respiratory landscape. The state’s Chief Medical Executive maintains a standing recommendation that anyone over six months old who hasn’t received the 2025-2026 COVID-19 vaccine should be considered at high risk for severe outcomes. The Michigan Department of Health and Human Services has issued updated 2025-2026 respiratory vaccine recommendations that include COVID-19 alongside flu shots.
COVID symptoms now largely overlap with flu and other respiratory viruses: sore throat, congestion, cough, fatigue, and sometimes fever. Testing remains the only reliable way to tell them apart. If you’re experiencing respiratory symptoms and want to know what you’re dealing with, combination flu and COVID rapid tests are widely available at pharmacies.
No Active Measles or Whooping Cough Outbreaks
Despite national concern about measles resurgences, Michigan currently has zero confirmed measles cases and no active monitoring in place. A previously reported case in Ingham County was removed from the state’s count after further testing ruled out measles. There are no reported whooping cough outbreaks flagged by the state health department either.
How to Tell What You Have
With flu, COVID, norovirus, and common colds all circulating at the same time, symptoms can blur together. A few patterns can help you sort it out:
- Flu (especially influenza B right now): Sudden onset of fever, body aches, chills, and exhaustion. Cough is common but congestion may be mild. Tends to knock you flat quickly.
- COVID-19: Similar to flu but more likely to include sore throat and congestion early on. Loss of taste or smell is less common with current variants but still possible.
- Norovirus: Vomiting and diarrhea are the hallmarks, often starting suddenly. Fever may be mild or absent. Respiratory symptoms are not typical.
- Common cold: Gradual onset, mostly congestion and runny nose. Low or no fever. You feel lousy but functional.
If your symptoms are primarily gastrointestinal, norovirus is the most likely culprit given current activity levels. If they’re respiratory with a high fever and body aches, flu is the top suspect, particularly influenza B in the western and central parts of the state. Testing is the only way to confirm, and knowing your diagnosis matters because antiviral treatments for flu and COVID work best when started within the first 48 hours of symptoms.
Protecting Yourself Right Now
Handwashing is the single most effective measure against all of these illnesses, but especially norovirus, which resists hand sanitizer. For respiratory viruses, staying home when symptomatic prevents the most spread. Michigan’s health department is actively recommending updated flu and COVID vaccines for the 2025-2026 season, and getting vaccinated now still offers protection during the tail end of respiratory virus season.
If you’re caring for someone with a stomach bug, clean contaminated surfaces with a bleach solution rather than standard household cleaners. Norovirus can survive on countertops and doorknobs for days. Wash any soiled clothing or bedding on the hottest setting available and dry completely.