Stomach flu is the name that people commonly use to describe viral gastroenteritis. Many factors affect how long it lasts, but it typically resolves within days.

The stomach flu causes inflammation, irritation, and swelling in the gastrointestinal (GI) tract. In most cases, it is relatively short lived and does not require treatment.

Several viral infections can be responsible for viral gastroenteritis, including:

  • Norovirus: This virus is the most common cause in adults.
  • Rotavirus: This type of infection tends to affect infants aged 3–15 months.
  • Adenovirus: Adenoviruses affect children under 2 years of age.

Despite its name, none of the viruses that cause the stomach flu are related to influenza. Different viruses affect the GI tract, causing symptoms such as nausea, vomiting, and diarrhea.

A person’s age and the type of viral infection can play a role in how long the stomach flu lasts.

In this article, we provide more information on the duration of stomach flu, including how long it remains contagious. We also offer some tips on recovery.

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Stomach flu typically does not last for a long period. However, different viruses may cause people to feel sick for different lengths of time.


According to the Centers for Disease Control and Prevention (CDC), norovirus is the most common cause of stomach flu, causing 19–21 million cases in the United States each year.

Norovirus symptoms generally last for about 1–2 days.

The virus spreads very easily and can stay on surfaces for several days or even weeks. Due to this, it can spread particularly easily in shared enclosed spaces, such as day care centers and nursing homes.

The CDC say that the virus becomes transmissible from the day a person starts feeling symptoms to a few days after the symptoms ease.

Therefore, it is important for a person with norovirus to avoid close contact with others for several days once they recognize that they have symptoms.

The best defense against norovirus is to avoid catching it.

The CDC recommend that people take the following steps to avoid catching the virus or prevent its transmission:

  • washing the hands thoroughly after using the bathroom or handling diapers and before eating
  • cleaning and disinfecting surfaces that come into contact with vomit or diarrhea
  • washing fruits and vegetables thoroughly and cooking seafood to a safe temperature
  • washing laundry thoroughly
  • refraining from preparing food or caring for other people when sick


According to the CDC, the people most at risk of getting rotavirus include:

  • children aged 3 months to 3 years
  • older adults
  • adults who work with children
  • people with a compromised immune system

A vaccination is available for rotavirus. Doctors typically give babies a dose of the vaccine two to three times between the ages of 2 and 6 months.

Rotavirus can cause fever, stomach pain, vomiting, and severe, watery diarrhea. A person normally develops symptoms about 2 days after exposure to the virus.

The symptoms can take 3–8 days to clear. A person may get rotavirus from touching contaminated stool, objects, or food.


The American Thoracic Society state that adenovirus actually comprises several different viruses.

They also note that once a person has had exposure to adenovirus, they may experience symptoms within 2 days to 2 weeks. In addition to GI symptoms, adenovirus can cause upper and lower respiratory symptoms, as well as neurological and eye disorders.

Adults and children who are otherwise in good health take about 5–7 days to recover from the viral infection.

However, even when the virus is no longer producing symptoms, it can spread to others. Adenovirus can also live for up to 30 days on hard surfaces.

Rotavirus and adenovirus are both common causes of stomach flu in young children. Rotavirus can last for about 3–8 days, and adenovirus can last for about 5–7 days.

Young children who are sick are most at risk of developing dehydration.

Parents and caregivers should look for signs of dehydration in children. These include:

  • urine that is darker in color
  • thirst
  • dizziness
  • less frequent urination
  • dry skin

Viruses responsible for the stomach flu remain contagious even after the infection passes.

Therefore, they are still transmissible from a person for several days after the symptoms pass.

These viruses can also live on surfaces for several days to weeks.

If someone in a household or other shared residence comes down with the stomach flu, people should clean all surfaces to remove the virus.

People can take a few basic steps at home to help boost their recovery.

Tips for children

Parents and caregivers can try the following to help speed up recovery in infants or children with the stomach flu:

  • continuing formula feeding or breastfeeding the infant as long as they can keep it down
  • starting solid foods slowly with easy-to-digest foods
  • avoiding giving too much water to older children
  • avoiding giving water to a baby with the stomach flu
  • asking a pediatrician about drinks to aid rehydration
  • providing light fluids in the form of diluted juices, broths, and ice chips

Tips for adults

People can help themselves recover by:

  • avoiding large meals
  • resting as much as possible
  • drinking sports drinks and plenty of water
  • eat softer, easy-to-digest foods, such as noodles, rice, and oatmeal

For most children and adults, the virus will run its course within a few days and will not require any special medical attention.

However, a person should look out for symptoms that might indicate a more serious issue. Parents and caregivers of infants and young children should watch for signs of dehydration.

A person should also call their doctor if:

  • the child or infant has blood in their stool
  • the stool is tar-like
  • symptoms do not improve within a few days
  • the child or infant develops signs of severe dehydration

Stomach flu does not last very long in children or adults.

It typically clears up within 2–8 days, depending on the virus that causes it.

There are no formal treatments, but rest, fluids, and easy-to-digest foods can help ease the symptoms.

After a person’s symptoms go away, the virus might still be contagious for several days.

People can reduce their risk of getting sick by avoiding close contact with those who have the illness. If someone in their household has the stomach flu, they should clean all surfaces thoroughly and wash any towels, bedding, and other materials that the person uses.