SAN FRANCISCO (KPIX/KCBS) — Health officials are warning of a widespread flu outbreak in the San Francisco Bay Area, in the wake of three recent flu-related deaths.

The three deaths occurred in Monterey, Solano and Napa counties.

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Cara Hoover, with the San Francisco Health Department, says we are now right in the middle of peak flu season, which typically runs December through February and sometimes carries through May.

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Officials are urging people to get flu shots, saying the shot is expected to provide good protection against the virus this year.

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People at highest risk include adults over 65, children under age 5, pregnant women and people with asthma, heart disease, or medical conditions that can weaken the immune system.