SAN FRANCISCO (KRON) — Fever, cough, sore throat, stuffy noses and head and body aches associated with the flu have already started taking hold of adults and children across the United States.

While much of the U.S. is seeing red or heavy flu activity, it remains yellow or moderate in California, still physicians are concerned.

“We’re having an earlier flu season and it may last for longer, don’t know where its going but it could be getting much more serious,” said Dr. Vincent Tamariz, pediatric ER medical director at California Pacific Medical Center. 

Tamariz is the medical director of CPMC pediatric emergency room.  

He says peak flu season in California is typically hits in January and February and he says parents should be on the lookout for flu symptoms in their kids, especially those under the age of 5.

“What you are looking for is something not drinking well  or eating well,” Tamariz said. “Someone very lethargic, they are breathing harder and faster, they may be panting, and when breathing you may see their ribs and they look like they are in some distress.”

In addition to children, pregnant women, seniors and those with long term health issues are most vulnerable. 

That’s why Tamariz advises those six months and older get the vaccine, which he says is proving to be more effective this year than last.

“It’s about 50 percent effective, which is very good compared to other years and even if you get the flu you will get a lesser form of it.”

In terms of reducing your risk of getting the flu in addition to the vaccine, doctors recommend a lot of hand washing.

To reduce the spread, they advise if you have the flu don’t go into work and if your kids have the flu don’t let them go to school.