In the Bay Area, there's an increase in cases of COVID, the flu, and a respiratory virus known as RSV, which doctors call a "triple threat."
All three viruses are hitting the east coast and cases are now starting to climb in the Bay Area.
Doctors say the flu is already circulating and they expect more cases in the coming weeks, so they recommend people to get a flu shot.
Hundreds of people have showed up to a Kaiser clinic in Santa Clara to get their shot, including 74-year-old David Senesac.
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"I've gotten one every year and if you work in a big office, then you'll be around a lot of sick people and I rarely get sick. It's because I get the flu shot" he said.
Dr. Darvin Smith, Chief of Infectious Disease at Kaiser Redwood City said there is reason to believe this could be a bad flu season.
"A lot of people haven't been vaccinated here or exposed to flu, so that makes us more susceptible to flu not having immunity from exposure or as many vaccines as usual," he said.
He also said cases of RSV or Respiratory Syncytial Virus is on the rise, and is showing up earlier in the season than usual.
"It's an upper respiratory viral infection similar to colds, and can be quite serious especially if you are immunocompromised or very young," he explained.
Experts at UCSF Benioff Children's Hospital Oakland said they have seen a recent surge in RSV cases in children under age 3.
All while this happening, COVID remains a threat as subvariants circulate.
Doctors are urging people to wear masks in crowded areas, get the bivalent COVID booster shot and the flu shot as well.
Editor's Note: A previous version of this story incorrectly stated that doctors called the threats as "tripledemic." It has since been corrected to "triple threat."
