FRESNO, Calif. (KFSN) -- California has yet to be hit with the flu outbreak that's already swept through 43 states, but medical experts worry the virus is ready to hit the West Coast hard.
The long Christmas break is winding down, and kids are beginning to head back to school after spending time with family, friends and holiday visitors. It's a big reason why doctors are worried the flu could quickly spread.
"Influenza B is at 15 percent across Northern California in our patients and a lot of that is in the school-age children, so we expect those kids who don't have it yet will get it and then they'll bring it home," said Dr. Dee Lacy, an infectious disease physician for Kaiser Permanente.
Dr. Lacy has noticed a recent rise in flu cases. She says parents can help limit the spread of the virus by making sure sick kids are well enough to go back to school.
"When they're no longer having fevers. We would like them to teach their kids to cough in their sleeves, cover their coughs and wash their hands frequently, wipe down common-touch surfaces," said Dr. Lacy.
Early government data shows we could be headed for a severe flu season. This year's vaccine has not been very effective.
"The flu vaccine, it's a bad match for this strain of H3N2," ABC News medical consultant Dr. Richard Besser said.
Still, Dr. Lacy urges everyone to get a flu shot because it can provide partial protection.
The flu has already claimed the lives of 21 children this season. Typically, the flu season peaks in January or February.
Flu ready to hit West Coast hard, doctors say
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