Norovirus
Norovirus (also known as Norwalk virus) is the name of a group of viruses that can cause gastroenteritis (inflammation of the GI tract, commonly called stomach flu). Because it so often causes vomiting, norovirus is sometimes called the winter vomiting disease.
What You Need to Know
- Alcohol-based hand sanitizers do not work against norovirus particles. Instead, wash your hands thoroughly (at least 20 seconds) with soap and water.
- Norovirus symptoms typically last two to three days.
- If you’ve had norovirus, you can still be contagious 48 hours after symptoms have resolved.
What is norovirus?
Norovirus is a contagious virus that typically causes nausea, vomiting and abdominal cramping. In the United States, norovirus is the leading cause of foodborne illness as well as vomiting and diarrhea.
You can catch norovirus at any time of year, but it peaks between November and April.
Norovirus Symptoms
After exposure, symptoms of norovirus typically begin within one to two days. Symptoms (listed in order of frequency, starting with the most common) include:
- Nausea and vomiting, often very frequently
- Abdominal pain/cramping
- Diarrhea
- Fever
- Fatigue
- Headache
These symptoms can come on quite suddenly.
How long do norovirus symptoms last?
Norovirus symptoms can last two to three days. Keep in mind that you can still be contagious up to 48 hours after your symptoms subside.
People with underlying conditions may experience longer or more severe symptoms.
How does norovirus spread?
The disease is spread through virus particles in vomit and feces. When you’re sick, you spread billions of these tiny virus particles. Unfortunately, norovirus particles are very hardy: They can last several days on solid surfaces, endure a wide range of hot and cold temperatures and withstand alcohol-based hand sanitizers.
There are several different ways you can catch norovirus:
- Touching your mouth or nose after your hand has come in contact with a contaminated surface.
- Spending time in close proximity to those infected with norovirus.
- Eating food contaminated with norovirus.
- Leafy greens, fresh fruits and shellfish are the foods most often linked to norovirus outbreaks.
How to Prevent Norovirus
Take the following precautions to prevent norovirus:
- Frequently wash your hands with soap and water for 20 seconds or more. Note that alcohol-based hand sanitizers are not effective at killing norovirus particles.
- Avoid contact with anyone who has experienced vomiting or diarrhea within 48 hours. Likewise, do not eat food handled by someone who has had vomiting or diarrhea within 48 hours.
- Isolate from other family members if you are experiencing norovirus symptoms. If possible, use a separate bathroom.
- Thoroughly wash frequently touched surfaces, such as handles, doorknobs and countertops.
- Avoid eating uncooked shellfish (like oysters), which can be contaminated with norovirus in the wild. Seafood should be heated to at least 145 degrees Fahrenheit to kill norovirus.
- Wash fruits and vegetables before consuming.
The CDC has more tips to prevent norovirus and properly disinfect.
Norovirus Diagnosis
Typically, your doctor can diagnose norovirus based on your symptoms alone. If not, norovirus can be diagnosed with a stool sample, which is examined at a lab.
Norovirus Treatment
There’s no treatment for norovirus, but there are things you can do to manage your symptoms:
- Drink plenty of fluids to prevent dehydration. Vomiting and diarrhea can very quickly dehydrate you.
- Eat bland foods. When you have norovirus, your stomach and the rest of your digestive system are irritated and very sensitive.
- Stay close to a bathroom. Vomiting and diarrhea can become quite frequent.
- Rest. Norovirus symptoms are often exhausting, leaving you feeling tired and weak.
Keep in mind that you can be contagious 48 hours after your symptoms have ended. Try to continue isolating from others during that time.