The U.S. is seeing a "quad-demic" as cases of COVID-19, flu, RSV and norovirus spread at the same time. Experts said this is what you need to know.

While there is a whole host of viruses going around, there are thankfully no new viruses to fret about—the ones we have are bad enough.

— The flu, caused by influenza viruses that are always changing, leads to fever, chills, cough, sore throat, runny nose, body aches, headaches and feeling tired. Flu symptoms tend to hit more quickly than cold symptoms, and can last anywhere from a few days to two weeks.

Bon Secours and Prisma Health are implementing new visitor restrictions as cases of influenza and respiratory illnesses rise across the country.

Here are some ways to prepare for this cold and flu season as four illnesses circulate the country at one time.