Respiratory illness cases on the rise this holiday season: Here's what you need to know

SAN FRANCISCO (KGO) -- A warning from the Centers for Disease Control that the worst of the respiratory illness season is yet to come, and low vaccination rates are leaving the most vulnerable at risk.

"People went to Thanksgiving all over the country. There was a lot of flu in the southeast and gulf states, and then they came back home so it was just a matter of time before we caught up," said Peter Chin-Hong MD, UCSF.

UCSF's Dr. Chin-Hong is talking about the flu and the rapid rise in hospitalizations.

"In California, it's up 400% in the last month, and it's rising very quickly," he said. California is now one of the most impacted states in the country.

But the good news? Dr. Chin-Hong says there's still time to get protected.

"It's still enough time to get the flu shot, and the flu shot is really well matched with what's circulating," said Dr. Ching- Hong.

MORE: COVID-19, flu continue to increase but CDC director believes US has hit peak of RSV

But also circulating are the new variants of COVID-19.

"We have a couple of emerging variants around and you may need to bolster your immune system a little bit more for some of these variants," he said.

But so far, the numbers are low.

"More people are going for the flu shot, about 40% of the population are getting that. Including kids. Fewer people are going for COVID shots, about 17% of the population But most concerning. Only about 37% those over 65," Dr. Chin-Hong said.

MORE: RSV in winter 2023: Everything you need to know about symptoms, treatments, shots

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"I do worry about it. I already had three times COVID, so yes, I do worry," said Sue Mattos, 66, who says she's keeping up with the vaccines and taking precautions.

"Actually I'm going to tonight, a party. We are all trying to get a COVID test. I already had mine today," she said.

Meanwhile, the younger people we spoke to didn't seem to have a worry.

"I have noticed that people are wearing more masks than before, but that's it - I'm not really concerned about it," said Jose Chavez from Los Angeles.

MORE: 230,000 more doses of new RSV immunization for babies are on the way, White House says

More hard-to-find doses of Beyfortus, the new immunization against respiratory syncytial virus (RSV) for infants, will be available in January, the White House says.

"But for me, not really, it doesn't affect my plans...unless the situation gets more severe," said Grace Huang, a San Francisco resident.

And, it could get more severe with COVID cases expected to peak in the New Year.

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