Norovirus, often called “the winter vomiting bug,” is the cause of 19-21 million cases of inflammation of the gastrointestinal tract in the U.S. per year, according to the U.S. Centers for Disease Control (CDC), and more than 685 million cases worldwide according to the World Health Organization. It’s easily transmissible and very contagious.

“Viruses like norovirus are well equipped for staying alive outside of the host and can live outside the body for up to two weeks on surfaces,” said Jonathan Jacobi, an employee workplace health and safety expert at UL Environmental Health and Safety. “Assume everything is contaminated because you don’t know if it is or isn’t, and people can be spreading norovirus before they feel sick. Because of this, I think we need to live a bit differently and take important hygiene precautions, especially in the winter months.”

It only takes a few virus particles to make people sick, and an infected person can shed billions of particles while sick and before and after showing symptoms.

You can get sick by:

  • Having direct contact with an infected person
  • Eating/drinking contaminated food or water
  • Touching contaminated surfaces

Symptoms and treatment

If you come down with a norovirus, you can feel extremely ill and vomit or have diarrhea many times a day, according to the CDC. This can lead to dehydration, especially in young children, older adults, and people with other illnesses. You’ll want to prevent dehydration by drinking plenty of liquids to replace fluid lost from vomiting and diarrhea.

Watch for these symptoms of dehydration, and if you see them, seek medical care:
  • Decrease in urination
  • Dry mouth and throat
  • Dizziness when standing up
  • In children: crying with few or no tears and be unusually sleepiness or fussiness

How to tell norovirus apart from influenza

Influenza (the flu) infects the respiratory system, not the gastrointestinal tract like norovirus. Flu symptoms include fever or a feeling of chills/feverish, cough, sore throat, runny/stuffy nose, muscle/body aches, headaches and/or fatigue. The flu typically lasts longer, often up to two weeks, whereas the norovirus usually causes sickness for 24 hours to three days. Here’s what you need to know about influenza.

How to protect yourself and others

“By default, assume people are sick, so don’t touch a door handle and then rub your eyes, for instance. Overall, follow these six steps diligently, especially in the winter months,” Jacobi said.

1. Wash your hands often, especially before eating and while preparing food, and always after going to the bathroom, taking out the garbage, or petting an animal.

“Hand sanitizers are not completely effective. They don’t always kill the norovirus. You can use them, but also wash your hands, which may physically move the virus off of your hands,” Jacobi said.

To properly wash your hands, according to the CDC: Wet your hands with clean, running water, turn off the tap, and apply soap. Lather your hands by rubbing them together with the soap and include your hands, between your fingers and under your nails. Scrub your hands for at least 20 seconds. Rinse your hands well under clean, running water. Dry your hands using a clean towel or air dry them.

2. Wash fruits and vegetables thoroughly. Although this will not kill the norovirus, it will help to physically remove the virus from the fruits and veggies.

3. Stay home when sick and for another two days after symptoms stop, according to the CDC. This is because people are most contagious before getting sick, while sick and in the first 48 hours after symptoms subside.

“Rest while sick, and then try to work from home for that key 48 hours post-recovery where you’re still able to easily spread the virus,” Jacobi said.

4. Don’t prepare food or provide healthcare for others when you’re sick, advised the CDC. Wait to prepare food or provide healthcare for at least two days after symptoms stop.

5. Keep sick people separated.

If you’ve got a sick loved one, don’t mix them up with others, instead let them sleep in their own room and eat by themselves, and be extra careful with items they touch knowing that these are contaminated and spread the norovirus, Jacobi said.

6. Clean and disinfect surfaces after someone vomited or had diarrhea. The CDC goes into detail as to how to do this: Wear gloves, put on a disposable mask, wipe the area with paper towels, then disinfect the area using a bleach-based household cleaner. Leave the bleach disinfectant on the affected area for at least five minutes, then clean the entire area again with soap and hot water. Finish by putting soiled laundry into the washing machine, taking out the trash and washing your hands.

Jacobi added: “A sick person’s clothing and linens needs to be washed alone so that it doesn’t spread viruses onto anyone else’s clothing. Wash and dry on the hottest setting. Then run a sanitization cycle in the washer between the sick person’s and other people’s clothing.”

Following these tips will lower your risk of getting norovirus and other sicknesses this winter, and hopefully keep you healthy all year long.