SAN FRANCISCO (KGO) -- The first cases of influenza have been detected in Marin County pointing to the start of flu season which typically kills thousands of people each year.
On average influenza kills between 20,000 - 50,000 Americans each year, and now experts are concerned we might be entering a "twindemic" with cases of the COVID-19 variant omicron likely to rise.
"We don't know whether Omicron will add substantially to that or not. But, Delta is enough of a problem as it is. We don't want people ending up at the hospital with Delta and people winding in the hospital with the influenza and hospital beds getting filled and the ICU beds getting with both of these patients," said Dr. John Swartzberg, UC Berkeley Clinical Professor Emeritus & Infectious Disease Expert.
Dr. Swartzberg says we are about two weeks from seeing how fast influenza will spread this year.
That's about the same time scientists say we'll have more data on omicron's transmission rate. Based on this data, experts says the flu shot is necessary.
"These vaccines have been well known and well established. This year we have all the vaccines being what we call quadrivalent meaning they cover the four types of influenza," said Dr. Swartzberg.
Dr. Swartzberg pointed to an outbreak of influenza at the University of Michigan with more than 500 cases.
Marin County's Health Officer, Dr. Matt Willis reported the first influenza cases of the season.
"It's looking like it may be a challenging winter for us," said Dr. Willis and added, "Our surveillance has shown that influenza is starting to ramp up in Marin county and that is true across the region. Typically mid-December is when we start seeing a spike in influenza cases."
Nationwide, the CDC reported an increase of Influenza cases in recent weeks with 80% of cases among children and young adult's ages 5 to 24 years old.
"We are more concerned that we would see a surge in COVID-19 related illness due to omicron. The last thing we need is people coming in with Influenza at the same time," said Dr. Willis.
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