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What You Need to Know

Flu cases and related hospitalizations are increasing across California as a new influenza A strain, H3N2 subclade K, circulates in the state. The California Department of Public Health is urging everyone aged six months and older to get vaccinated, to test patients promptly when flu symptoms appear, and to begin antiviral treatment immediately for those at high risk.

In a statement issued on January 14, the California Department of Public Health (CDPH) is alerting health care providers and the public that influenza (flu) activity and hospital admissions are increasing across the state. A newly emerged influenza A strain, H3N2 subclade K, is circulating globally and has been detected in California.

“Current seasonal flu vaccines remain effective at reducing severe illness and hospitalization, including the currently circulating viruses,” said Dr. Erica Pan, CDPH Director and State Public Health Officer. “It is important for families to know that flu vaccines, tests, and treatments remain widely available for all Californians and that it is not too late to get a flu vaccine. As a pediatrician, parent, and daughter, I have made sure that my own family is protected with this season’s flu vaccine.”

The California Department of Public Health has also confirmed the state’s second pediatric flu-associated death of the season. Young children and older adults remain most vulnerable to severe complications, underscoring the importance of steps families can take to protect their health.

Take Action

  • Vaccinate Now: Health officials urge everyone aged six months and older who has not yet received the 2025–26 influenza vaccine to get vaccinated as soon as possible. Vaccination remains the most effective protection against severe illness and hospitalization. Appointments can be scheduled through a health care provider, a local pharmacy, or at myturn.ca.gov.
  • Test Promptly: People with flu symptoms who are at risk for serious illness should contact their doctor to determine whether testing is needed and whether they could benefit from treatment. When available, at-home combined influenza and COVID-19 tests may also be used.
  • Start Antivirals Immediately: High-risk individuals and hospitalized patients with suspected influenza should begin antiviral treatment immediately, without waiting for test confirmation. Recommended options, including oseltamivir and the single-dose baloxavir, can reduce the risk of severe illness and hospitalization.

Coverage and Availability

Despite changes to federal recommendations, vaccines recommended by the California Department of Public Health will continue to be covered at no cost by state-regulated health insurers. These vaccines remain available through local pharmacies, health care providers, and other authorized vaccinators. Appointments can be scheduled through a health care provider, a local pharmacy, or the state’s vaccination website: myturn.ca.gov.

Resources

For updates on influenza and other respiratory viruses: CDPH Respiratory Virus Dashboard 

For healthcare providers, clinical guidance and resources: CDPH Influenza Update 

For educational resources and downloadable materials about the benefits of the flu vaccine: CDPH Flu Vaccine Toolkit

For more information about flu prevention and vaccine eligibility: CDPH Influenza