This year’s flu season is coming on earlier than usual in Orange County, where dozens of people have already been sickened and at least two have died.
That’s more than in Los Angeles County, where doctors say they expect a spike, but few cases have been reported so far.
"The West Coast has seen less of the disease burden so far," said Dr. Matt Zahn, who heads medical epidemiology for Orange County Health Care Agency. "But the last couple of weeks at least in Orange County that has changed."
Zahn said that local laboratories are reporting a jump in cases of flu specifically – not just colds and illnesses that people may think are flu.
"We have had a big increase in the number of reported laboratory tests of Influenza A and Influenza B,” he said.
It is not clear how many people have died in Orange County, because public health laws only require doctors to report the death if the patient is younger than 65.
The two men who the county knows about, Zahn said, were both under that age, although one was weakened by another medical condition.
That younger people succumbed to flu is significant, he said, because it means that this year’s flu strains can cause severe illness in younger, presumably stronger, people.
In Los Angeles County, one person has died of the flu, said public health spokesman Allen Solomon. In San Diego county, two deaths – including one case involving an 89-year-old woman, have been reported.
Doctors say the flu vaccine can decrease your chances of getting sick almost tenfold, and the federal government recommends everyone 6 months and older get the vaccine. The antibodies kick in within two weeks, which is about when they predict the Southern California flu season will be at its peak.
"You really want to not end up in that crowd in the ER waiting four hours to be seen. The easiest way to avoid that is to get vaccinated ahead of time," said Dr. James Keany of Mission Hospital in Mission Viejo.
NBC4's Vikki Vargas contributed to this article.