5 Norovirus Symptoms That Can Hit You Really, Really Hard

Just in case you haven’t heard this enough yet: You should really, really be washing your hands well and often. It’s one of the most important things you can do to avoid norovirus, a nasty stomach bug that’s making lots of people sick lately.

Reported cases of the gastrointestinal virus, which tends to cause horrible diarrhea and vomiting for roughly one to three hellish days, have steadily risen in the United States since August 2022, according to data from the Centers for Disease Control and Prevention (CDC). Confirmed infections are climbing across the country but were highest in the southern and northeastern regions as of late February.   

Norovirus, which is the most common cause of viral gastroenteritis (a.k.a. the stomach flu) spreads like wildfire, often through direct contact with someone who’s infected—say, by caring for a sick person, or by sharing food or eating utensils with them. You can also get norovirus by touching contaminated surfaces, like a door or toilet handle, and then touching your face with unwashed hands.

Experts aren’t totally sure why there’s such a noticeable uptick in cases, but it’s worth noting that norovirus is somewhat seasonal, Christopher Cao, MD, an assistant professor of gastroenterology at the Icahn School of Medicine at Mount Sinai in New York City, tells SELF. “It’s a year-round [virus], but we hear about it more in the winter,” Dr. Cao says. (Research suggests the virus fares better at lower temperatures. Per the CDC, cases tend to increase and persist in the late fall, winter, and early spring.)

Trust us, you don’t want to deal with this pathogen. The symptoms of norovirus are pretty intense—and chances are, you’ll quickly know something’s up once they hit. Here are the most common signs of norovirus to watch out for—and when it’s time to see a doctor if you’re feeling super sick.

1. Terrible stomach cramping or pain

It’s easy to write off an upset stomach, but the abdominal cramping and pain typically caused by norovirus will be hard to ignore. Many people also experience uncomfortable nausea, per the CDC.

2. Diarrhea, vomiting, or both

Norovirus often cause persistent diarrhea and vomiting—sometimes both at the same time, Rabia A. De Latour, MD, a gastroenterologist and assistant professor of medicine at NYU Langone, tells SELF. Per the CDC, it isn’t unusual to feel “extremely ill” and experience diarrhea or vomiting multiple times a day if you’re infected with norovirus. (That said, norovirus shouldn’t cause any blood in your stool.)

3. Body aches and other flu-like symptoms

Your GI tract may not be the only part of your body that’s in pain: Norovirus can also cause muscle aches (similar to those caused by the flu), fatigue, and headache, per the CDC. These are common symptoms of many infectious illnesses; when your immune system jumps into action to fight the harmful pathogen, your protective cells trigger inflammation, which can lead to soreness and make you feel really tired.  

4. Fever and chills

A low-grade fever—meaning your temperature is somewhere between 99.6 and 100.3 degrees Fahrenheit—is a normal symptom of norovirus, as are the chills. Like muscle aches, a fever can be a sign that your body is fighting an infection, and it can cause you to feel clammy or sweaty.

5. Signs of severe dehydration

Because norovirus can cause seemingly nonstop diarrhea and vomiting, it’s essential to be aware of your fluid intake once symptoms hit, Dr. Cao says: “One of the most frequent symptoms we see in patients is dehydration.” This, in turn, can lead to muscle cramps, headaches, dizziness or lightheadedness, dark-colored urine, dry mouth, exhaustion, or feeling confused, as SELF previously reported.

When to see a doctor about norovirus symptoms

If you have any of the potential norovirus symptoms above and they don’t settle down after 48 hours, it’s time to seek medical care, Dr. De Latour says. If you have a primary care doctor and you’re able to get an appointment with them, that’s a good place to start. (If not, consider visiting an urgent care center, especially if you can’t keep any food or fluids down.) If your health care provider suspects something else is causing your symptoms, they’ll be able to point you in the right direction.