Flu cases in Pima County are climbing above recent seasonal averages, with more than 2,700 confirmed infections reported so far this respiratory season, according to local health officials.

Statewide totals have also continued to rise, as Arizona records more than 20,000 cases and the Centers for Disease Control and Prevention classifies this year’s flu activity as moderate in severity. Health experts say children ages 5 to 17 are currently the most affected group in the county.

The Pima County Health Department defines flu season as running from late September through late September of the following year.

The department has confirmed 2,723 cases for the 2025-26 season, compared with 7,344 reported during the 2024-25 season.

Experts warn that cases in the county and across the state will continue to rise, noting high levels of activity compared with the five-season average.

“Our total flu cases this 2025-2026 respiratory season is slightly higher than our 5-season average total flu cases within a similar timeframe,” said a Pima County Health Department spokesperson. “Nationally, the CDC is classifying this flu season as ‘Moderate Severity’ across all ages.”

Symptoms of the flu include sore throat, cough, runny nose, body or muscle aches, headaches, tiredness and vomiting or diarrhea.

The health department said children ages 5 through 17 have been most affected by the flu, followed by people ages 18 through 49, then adults 65 and older.

Children ages 5 through 17 account for 33% of flu cases in Pima County, with adults 65 and older following at 18% of cases.

The Health Department is encouraging schools and child care programs to alert the Epidemiology Division if they suspect an outbreak has occurred.

“As we move through cold and flu season, our teams are fully prepared for any increase in cases,” said El Rio Health Center spokesman Nathan Holaway. “We encourage all patients and community members to stay up to date on recommended vaccinations to help reduce the spread of illness.”

Thirty-seven percent of adults reported receiving a flu vaccine in Arizona in 2024, according to America’s Health Rankings. Vaccination data for the most recent season is not yet available.

Nationwide, there have been approximately 12,000 flu-related deaths, according to the Centers for Disease Control and Prevention, with about 66 of those deaths occurring in children under the age of 18.

During the 2024-2025 season, 18,400 deaths in the country listed “influenza” as a contributing or underlying cause of death. Local data has not been released.

“While the Epidemiology Division constantly investigates reportable diseases to the local Health Department, they work closely with the Emergency Management and Preparedness Division to plan for large-scale outbreak response where mitigation efforts, logistics and communications are coordinated,” according to the Pima County Health Department.

Zoey Oberstein is a University of Arizona student majoring in journalism and a Tucson Spotlight intern. Contact her at zoeyoberstein@arizona.edu.

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