This year's flu season hit a grim milestone with deaths tied to the virus surpassing the number of COVID-related deaths in California for the first time in five years.
The noteworthy milestone has the attention of health leaders.
"The glass is half-full and half-empty, and the half-empty part is we’re seeing the biggest increase in flu cases for the first time in more than 15 years," said Dr. Peter Chin-Hong, an infectious disease specialist with the University of California, San Francisco.
While the numbers show a turning point with COVID getting weaker and killing fewer people, there is another side of the story. Some health leaders said California's flu season is shaping up to be one of the worst of this century.
The state also notes only a small percentage of eligible Californians have received the appropriate respiratory virus vaccines.
In fact, CDC data shows the percentage of kids getting vaccinated for the flu in California is nearly 10% lower than it was before the pandemic.
"Another infection is really vaccine hesitancy because that has spread from the COVID vaccine hesitancy to questions people have on all vaccines in all regards, including flu and child immunizations," Chin-Hong said.
The CDC estimates at least 24 million flu cases so far this season, with 310,000 hospitalizations and 13,000 deaths, including 57 children.
"During COVID we got used to the idea that only the very old are very vulnerable," Chin-Hong said. "But the flu is a very different beast all together."
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Local health officials said it is not too late to protect yourself.
"Flu viruses from year to year can cause more or less disease, but the recommendations from year to year remain the same -- stay up to date with your vaccinations," said Dr. Krishna Surasi, Santa Clara County's assistant public health officer. "For flu and COVID, that’s everybody six months and older. And then for RSV, it’s a little more complicated. Talk to your doctor, but it’s generally people that are very young or older."