Flu toll mounts in California, with 42 deaths so far

California's flu season has just begun to ramp up, but 42 people in the state have already died of influenza, according to officials.

The death tally began in October, the official start of the flu season nationwide. The season runs through May and typically reaches its height in February.

Older people are more likely to develop serious complications, such as pneumonia, after catching the flu. Half the deaths in California this season are among people over 65, according to state data.

In California and nationwide, the flu strain going around is H1N1, a kind of Influenza A known as “swine flu.” Nationally, 77 percent of flu cases so far have tested positive for H1N1, according to the U.S. Centers for Disease Control and Prevention.

H1N1 tends to be most dangerous for children and pregnant women, said Los Angeles County chief medical officer Dr. Jeffrey Gunzenhauser. So far this season, 10 people in L.A. County have died of the flu, he said.

Nationwide, there have already been two high-profile flu deaths this season.

On Dec. 24, an 8-year-old boy who was being held in U.S. custody in New Mexico after being apprehended at the border died of the flu. Later that same week, Bre Payton, a 26-year-old writer for online magazine the Federalist, died of encephalitis caused by the flu, according to her employer.

In general, however, health officials say this year's flu season will probably be milder than the last, when the deadly H3N2 strain was the most prevalent across the country. Then, so many people fell ill that hospitals overflowed with patients and ran out of medicines. The season led to one of the country's highest flu death tolls ever, second only to the 1918 Spanish flu pandemic that killed thousands, according to Gunzenhauser.

Although H1N1 tends to be a less harmful strain, Gunzenhauser still encourages everyone older than 6 months of age to get vaccinated, especially as cases pick up on the West Coast. The vaccine takes about two weeks to take effect.

“We don't want to discourage anyone from being vaccinated,” he said. “Right now we're early - we're starting to see that rise.”

The flu shot reduces a pregnant woman's chance of catching the flu by 40 percent and provides immunity for her baby, he said. People who receive the shot and then still catch the flu typically experience less severe symptoms.

Last year's flu season killed 185 children, 80 percent of whom were not vaccinated, according to the CDC.