"Super flu" causing a spike in Indiana flu cases
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Flu cases are rising in Indiana this winter, mirroring a national surge tied to the so-called super flu.
Why it matters: An unprecedented rise in flu cases comes as other sicknesses, such as the "norovirus," COVID and whooping cough, are slamming the country.
Driving the news: New data shows that there have been at least 7.5 million illnesses, 81,000 hospitalizations and 3,100 deaths from the flu so far this season.
Zoom in: Indiana is one of 30 states with "very high" flu activity, per the latest CDC update.
- According to the Indiana Department of Health, Indiana has recorded 17 flu deaths this season, including three during the week ending Dec. 27.
- Six of those deaths were recorded in Marion County, the most of any county.
- The final week of 2025 also saw emergency room visits for the flu increase by 37% in Marion County when compared to the previous week, and 7% of all emergency room visits had flu symptoms.
State of play: The surge has led to visitation restrictions at facilities within the Community Health Network, Indiana University Health, Ascension St. Vincent and Franciscan Health systems.
The big picture: The dominant flu strain right now, a version of H3N2, emerged over the summer. In the fall, health officials in the U.K. and Canada warned that the new strain was causing a rise in hospitalizations in their countries.
Reality check: There isn't an official "super flu."
- The term emerges every so often, typically when there's a more severe-than-usual strain of the flu circulating, experts say.
- This time around, subclade K is being associated with the term.
- The most recent CDC tracking data shows that nearly 90% of new flu cases in the country were from subclade K, which appears to be the super flu this time around.
Symptoms associated with H3N2 aren't different from those of the common flu and include sore throat, runny nose, fever, cough, muscle aches, tiredness and chills.