Most experts recommend kids over 6 months old get a flu vaccine.
The death occurred last month involving a child who had not received this year's flu shot, and county officials said they did not know if there were underlying health conditions in the case. It is the second flu-related death in San Mateo County this season.
Flu activity is continuing to climb across the U.S. as hospitalizations rise, updated data from the CDC shows.
Hospitals in the Bay Area are reporting more "influenza-like illness," pointing to a mutation in the strain. Medical experts are recommending to still get vaccinated to prevent severe illness, especially those over 60 years old or young children, and ask your doctor about an antiviral medication.
This flu season seems to be getting worse by the day, according to health officials. The bulk of this year's cases are being linked to a new variant known as subclade K.
New York City is seeing some of the highest levels in the country.