Health Alert

Chicago Flu Season 2025-2026: H3N2 Strain Dominates

Influenza A H3N2 is the dominant flu strain in Chicago this season. Learn about symptoms, treatment, and when to get vaccinated.

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Ickly Editorial
January 20266 min read
#Chicago

Flu Activity Increasing Across Chicago

The 2025-2026 flu season is ramping up in Chicago, with test positivity rising from 3.7% to 4.7% in recent weeks. The Chicago Department of Public Health reports that Influenza A accounts for 98% of typed specimens, with H3N2 being the dominant subtype.

Why H3N2 Matters

According to the CDC's flu surveillance data, H3N2 strains are historically associated with:

  • More severe illness in young children and elderly
  • Higher hospitalization rates compared to other flu types
  • More complications like pneumonia and ear infections

Flu Symptoms in Children

The American Academy of Pediatrics notes that flu comes on suddenly and hits hard:

Common Symptoms

  • High fever (often 102-104°F)
  • Severe body aches
  • Headache
  • Extreme fatigue
  • Dry cough
  • Sore throat
  • Runny or stuffy nose

How Flu Differs from a Cold

SymptomColdFlu
OnsetGradualSudden
FeverRareCommon, high
Body achesMildSevere
FatigueMildExtreme

Flu Vaccine: It's Not Too Late

According to the CDC's vaccination guidelines, if your child hasn't been vaccinated yet, now is the time:

  • Who should get it: Everyone 6 months and older
  • Where to go: Pediatrician, pharmacy, or CDPH immunization clinics
  • Cost: Free through many insurance plans and city clinics

Chicago Free Vaccine Locations

  • CDPH standing immunization clinics
  • All 7 City Colleges of Chicago (pop-up events)
  • Community health centers throughout the city

Treatment Options

If your child gets the flu:

Antiviral Medications

  • Tamiflu (oseltamivir) can shorten illness duration
  • Most effective when started within 48 hours of symptoms
  • Ask your pediatrician if antivirals are appropriate

Home Care

  • Rest and fluids are essential
  • Fever reducers for comfort (not aspirin—see Reye's Syndrome warning)
  • Humidifier for congestion
  • Isolation from other family members

Flu Reports from Chicago Schools

Parents on Ickly are reporting flu outbreaks at schools across Chicago, with clusters in:

  • North Side neighborhoods
  • Northwest Side daycares
  • Loop-area preschools

Track what's circulating at your child's school by following it on Ickly.

When to Seek Medical Care

The CDC recommends calling your pediatrician or seeking emergency care if your child has:

  • Difficulty breathing or rapid breathing
  • Bluish skin color
  • Not drinking enough fluids
  • Severe or persistent vomiting
  • Flu symptoms that improve then return with fever and worse cough
  • Fever with a rash


Sources:

Is the flu going around your child's school? Report it on Ick to help other families prepare.

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Written by Ickly Editorial

Curated for parents and school directors

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