California health officials are urging vaccinations as flu cases rise, driven by the H3N2 subclade K strain, with a focus on protecting vulnerable populations.
Influenza cases and related hospitalizations are on the rise across California, prompting the California Department of Public Health (CDPH) to issue a strong recommendation for vaccinations. The emergence of a new influenza A strain, known as H3N2 subclade K, has been detected in the state and is circulating globally.
In a statement released on January 14, the CDPH alerted health care providers and the public about the increasing flu activity and hospital admissions. Dr. Erica Pan, CDPH Director and State Public Health Officer, emphasized the importance of vaccination, stating, “Current seasonal flu vaccines remain effective at reducing severe illness and hospitalization, including the currently circulating viruses.”
Dr. Pan further noted that it is crucial for families to understand that flu vaccines, tests, and treatments are widely available for all Californians. “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,” she added.
The CDPH has also confirmed the state’s second pediatric flu-associated death of the season, highlighting the vulnerability of young children and older adults to severe complications from the virus. This underscores the importance of proactive measures families can take to safeguard their health.
Health officials are urging everyone aged six months and older who has not yet received the 2025–26 influenza vaccine to get vaccinated as soon as possible. Vaccination is recognized as the most effective means of protection against severe illness and hospitalization. Individuals can schedule appointments through their health care provider, local pharmacies, or by visiting myturn.ca.gov.
In addition to vaccination, the CDPH recommends that individuals exhibiting flu symptoms, particularly those at risk for serious illness, should promptly contact their healthcare provider to determine whether testing is necessary and if they could benefit from antiviral treatment. At-home combined influenza and COVID-19 tests may also be used when available.
For high-risk individuals and hospitalized patients with suspected influenza, it is advised to begin antiviral treatment immediately, without waiting for test confirmation. Options such as oseltamivir and the single-dose baloxavir have been shown to reduce the risk of severe illness and hospitalization.
Despite recent changes to federal recommendations, vaccines endorsed by the CDPH will continue to be covered at no cost by state-regulated health insurers. These vaccines are accessible through local pharmacies, healthcare providers, and other authorized vaccinators. Appointments can be arranged via health care providers, local pharmacies, or the state’s vaccination website, myturn.ca.gov.
For ongoing updates on influenza and other respiratory viruses, the CDPH provides a Respiratory Virus Dashboard. Healthcare providers can access clinical guidance and resources through the CDPH Influenza Update. Additionally, educational materials about the benefits of the flu vaccine are available in the CDPH Flu Vaccine Toolkit.
For more information regarding flu prevention and vaccine eligibility, visit the CDPH Influenza page.
According to California Department of Public Health, taking these steps is essential to protect yourself and your loved ones during this flu season.