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NAPA (BCN) -- A Napa County resident under 65 years old died Thursday from the flu, which has become widespread in the San Francisco Bay Area, officials with the Napa County Public Health Division said today.
The officials said they are investigating the death and are not releasing any more information to protect the individual's privacy.
"This unfortunate case demonstrates that flu can be deadly," Napa County Health Officer Dr. Karen Relucio said.
California Department of Public Health officials said as of Dec. 30 there have been three flu deaths in the state.
Throughout the Bay Area, public health officials are urging everyone over six months of age to get vaccinated.
The officials have said this year's vaccine is effective since it protects against the season's most active strains.
In Napa County, public health officials are seeing a rapid increase in the percentage of patients seen in emergency departments with influenza like-illness, Relucio said.
The flu has reached "widespread levels" in California and areas with the most flu activity in the state include in the Bay Area, North Bay public health officers said.
Solano County public health officials on Wednesday confirmed the county's first flu death of the 2016-2017 flu season occurred last week.
The victim was under 65 years old and had a medical condition that put the victim at risk of severe illness, Solano County Deputy Public Health Officer Dr. Michael Stacey said.
In Marin County, flu transmission began the week of Dec. 11 and significantly increased the week of Dec. 25, Marin County public health officials said.
Flu cases peak in December through February and may continue into May in the U.S., according to public health officials.
"It's not too late to get vaccinated," Marin County deputy public health officer Dr. Lisa Santora said in a statement.
Vaccinations are available at pharmacies, doctor's offices and some employers offer vaccinations.
The people most vulnerable are those 65 years old and older, children five years old and younger, pregnant women and people with some medical conditions such as asthma, heart disease and weakened immune systems.