If you or your child get the stomach flu, it’s natural to wonder if everyone else in the family will get it too.
After all, many of us have caught an infection from a family member, friend, or coworker at some point in our lives.
However, the stomach flu is not actually a flu.
For one, the stomach flu is typically caused by norovirus, while influenza viruses cause the flu.
For another, the stomach flu (also called viral gastroenteritis) primarily affects the intestines and sometimes the stomach.
It does not cause upper-respiratory symptoms (like dry cough and nasal congestion) like the common flu does.
To help you and your loved ones stay healthy, in this article, we’ll explain if the stomach flu is contagious and how it spreads.
Then we’ll discuss symptoms and remedies for the stomach flu, followed by how to prevent viral gastroenteritis and when to see a doctor.
Is Stomach Flu Contagious?
The stomach flu is caused by norovirus or other similar viruses like rotavirus, adenovirus, or astrovirus.
These viruses are contagious and often lead to group or community-setting outbreaks such as in daycares, schools, nursing homes, or cruise ships.
How long does stomach flu last?
Most cases of viral gastroenteritis resolve on their own within a week.
People with weakened immune systems as well as young children and older adults are at greater risk of contracting stomach flu and may experience more severe symptoms.
How does stomach flu spread?
Most stomach flu is passed via a fecal-oral route of transmission.
As the name implies, this means that someone unknowingly ingested tiny particles of stool or vomit from an infected person. This can happen when:
- Someone touches the stool of a sick person and then touches their face without washing their hands.
- Someone touches the stool of an infected person and then touches a shared surface, such as a doorknob. If others touch that surface, they can pick up the germs and then touch their face without washing their hands.
- People consume contaminated food or water.
Stomach Flu Symptoms
Common symptoms of stomach flu include:
- Stomach cramps: Pain or discomfort in the abdomen is often the first sign of stomach flu. These cramps can be intense and are shortly followed by vomiting, diarrhea, or both.
- Vomiting: You may vomit only a few times, or feel nauseated and vomit for several days.
- Diarrhea: Diarrhea may occur after vomiting has stopped, or you may experience both symptoms together. Most people with the stomach flu go to the bathroom several times a day.
- Body aches: Not everyone experiences body aches, but they can be a sign of the stomach flu. Some people also experience headaches.
- Fever: A temperature up to 102.2° F (39°C) can occur as the body works to fight the virus.
- Dehydration: Because vomiting and diarrhea lead to fluid losses, and the loss of electrolytes naturally occurs during this process, you may experience dehydration. You can be dehydrated without feeling thirsty. Other signs of dehydration include urinating less often, darker color urine, and sometimes dizziness.
Stomach Flu Remedies
Although there is no way to speed healing from the stomach flu, you can do many things at home to ease your symptoms and find comfort while your body recovers.
What you should eat
Studies have mixed results about the best foods to eat for viral gastroenteritis.
However, erring on the side of caution and sticking to a bland diet may help ease further discomfort if you vomit and may make it easier on your intestines as they recover from the virus.
Many doctors recommend some version of a BRAT diet once you are ready to eat.
BRAT stands for:
- Bananas: In addition to being easy to digest, bananas contain potassium. Levels of this electrolyte may fall if you vomit often due to the stomach flu.
- Rice: White rice is an easy-to-digest grain with a mild flavor, so even people who feel nauseated can typically stomach it. Or try rice cakes or rice crackers. (Due to the higher fiber content, brown rice is harder to digest and may aggravate an upset stomach.)
- Apples: Apples and applesauce contain vitamins, are easy to digest, and take little time to prepare.
- Toast: Toasted white bread (either plain or with a little butter or fruit spread) is another easy-on-the-digestive-tract food since it’s low in fiber. And the carbohydrates will provide some energy. Whole-grain breads (including whole-wheat bread) have more fiber and may be harder to digest and less tolerable when you have an upset stomach.
Foods you should avoid
When you have the stomach flu, avoid any food that worsens your nausea, vomiting, diarrhea, or other symptoms. While everyone is different, you may find it best to stay away from the following foods until you feel better:
- Red meat: Although red meat contains beneficial nutrients (like iron and protein), leaner choices are easier for the digestive system to break down. Consider plain or lightly seasoned fish, chicken, or turkey instead.
- Spicy foods: Chili peppers, hot sauce, and other spicy foods can significantly worsen the pain and discomfort of vomiting or diarrhea. Stick to mild flavors until your symptoms fully resolve.
- Sugar: You may crave comfort foods like ice cream when you don’t feel well, but having sugary snacks and drinks (including sodas and sports drinks) may make diarrhea worse).
- Dairy: Avoiding dairy, even yogurt, should be until you feel that the symptoms are starting to resolve.
Recovery and How to Prevent Stomach Flu
Because it is caused by a highly contagious family of viruses, it’s not always possible to prevent stomach flu. However, you can reduce the risk of getting sick by practicing some simple habits:
- Wash your hands with warm soap and water on a regular basis, especially before eating, touching your face, or handling food.
- Disinfect shared surfaces or things that you frequently touch, like your smartphone, car keys, doorknobs, and faucet handles.
- Don’t share utensils, plates, or glasses.
- Wash vegetables and fruit thoroughly before preparing or eating them.
If you still get the stomach flu, recovery typically does not take longer than a week. Most people only need rest, proper hydration, and sometimes over-the-counter medication or a bland diet to cope with the illness.
When to See a Doctor
If you believe you have the stomach flu and do not feel better after 5-7 days, check in with your doctor. You may have a different virus or may have developed a secondary infection.
Also see a healthcare provider if you notice:
- A high fever
- Blood in your stool
- Symptoms of dehydration (such as dark urine, infrequent peeing, and lightheadedness
- Localizing stomach pains (pain that sits in one spot more than another)
- Hardness/swelling to one part of your abdomen
How K Health Can Help
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Frequently Asked Questions
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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Definition and Facts for Viral Gastroenteritis (Stomach Flu). (2018).
https://www.niddk.nih.gov/health-information/digestive-diseases/viral-gastroenteritis/definition-facts -
Norovirus. (2021).
https://www.cdc.gov/norovirus/index.html -
Viral Gastroenteritis. (2021).
https://www.ncbi.nlm.nih.gov/books/NBK518995/