6 questions about the flu you need answered right now

Literally millions of people get the flu every year, according to the Centers for Disease Control and Prevention. So you'd think we'd all know pretty much everything there is to know about the disease, right?

Wrong. There are plenty of flu misconceptions floating around out there. In fact, if you've ever neglected to get a flu shot because "sometimes it causes the flu," you're among those walking around with some serious misinformation.

That's why we asked Philip Tierno, M.D., a professor of microbiology & pathology at the NYU Langone Medical Center and author of , to set the record straight on the questions you need answered ASAP:

Let’s start with what’s the same. Both are respiratory illnesses that can cause a stuffy nose, and sore throat. Where they differ: “Colds are mostly relegated to the head, whereas the flu effects the entire body,” says Tierno. So if you’ve got a fever, the chills, a headache, and bone-tiredness, you’ve probably got influenza. BTW: If you’re vomiting, that’s an intestinal flu. The name is similar (confusing much?) but it’s a completely different viral infection.

Nope. In fact, “the flu shot is the best way to prevent the flu and it’s the safest vaccine in the world,” says Tierno. The jab contains inactive—not live—viruses, so it can’t pass along bad bugs. That said, your body can launch an immune-system response in reaction to the jab, so you might feel flu-y (achy muscles or a mild fever) for a day or two after the needle prick.

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No! Antibiotics are only useful in fighting bacterial infections, not viruses, and taking the meds when you don't need them can contribute to resistance to the drugs. Prescription antiviral drugs like Tamiflu or Rilenza can shorten a bout of influenza A (a swab test at the doctor’s office can diagnose which type you have) by about a day, but there’s a catch—you have to start taking them within two days of symptoms appearing for them to have any effect, according to the Centers for Disease Control and Prevention. Any longer and you’ll just have to let things run their course, says Tierno.

Brush up on your body knowledge with these fascinating anatomy facts:

While they won’t cure the flu, OTC drugs can minimize suffering while you’re under the weather. If you just have a stuffy nose, take a decongestant—they can shrink swollen mucus membranes in the nose, helping you breathe easier. “They can also lower the risk of getting a secondary bacterial infections like pneumonia,” says Tierno. A runny nose, on the other hand, can benefit from an antihistamine. If your chest is also congested, add an expectorant like guaigenesin, which will thin and loosen mucus. Cough suppressants (look for dextromethorphan on the label) can quieten hacking; nonsteroidal anti-inflammatory drugs (like ibuprofen) can help with headaches and fever.

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As long as you’re up to eating, it’s a great way to boost your immune system. Skip the tacos and slurp down some chicken noodle soup or bone broth—research suggests they contain immune-boosting vitamins and minerals that can reduce symptoms. (Learn how bone broth can help you lose weight with Rodale's .)

If you’re symptomatic at all, stay home. If your fever breaks (usually after four to six days), you can return to your office, but be extra vigilant with hand washing and throwing away dirty tissues. “You can still shed the virus a day or two after symptoms are mostly gone, so it’s possible to pass on to others,” warns Tierno.

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