Both are viruses and cause fever, cough, body aches, fatigue and sometimes vomiting and diarrhea.
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They can range from mild to severe, and both diseases are potentially deadly.
Neither virus is treatable with antibiotics, but the flu can be treated with anti-viral drugs that can help lessen symptoms and the duration.
One big difference is there is there is no vaccine for coronavirus, although several options are being studied.
Experts say your best bet to avoid the flu is to get a flu shot, and it's still not too late.
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