How Long Does the Stomach Flu Last?


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Summary
  • Stomach flu causes inflammation, irritation, and swelling in the stomach region
  • The stomach flu typically only lasts a few days
  • It is most commonly caused by a viral infection
  • The virus is incredibly easy to spread and can survive on surfaces for days or even weeks
  • Stomach flu can cause serious dehydration
  • Some common home remedies can help treat the stomach flu

Stomach flu, medically known as gastroenteritis, is a condition characterized by inflammation, irritation, and swelling in the gastrointestinal (GI) tract.

According to the CDC, a main culprit is the norovirus, a virus that causes stomach flu. Most outbreaks happen between November and April. The stomach flu typically lasts only a few days and can in many cases be treated with home remedies.

This article will explore the causes of viral stomach flu, its symptoms, how to treat it, and when you should consider reaching out to a doctor.

What is Stomach Flu?

Stomach flu (gastroenteritis) is a gastrointestinal infection (GI) that can be picked up through food contaminated with bacteria, or more commonly through close contact with a person infected by a stomach flu virus.

Viral stomach flu has a 1-3 day period during which no symptoms appear. Symptoms normally last one to two days after they start, and can last up to 10 days.

Common symptoms of stomach flu include:

  • Diarrhea

  • Vomiting

  • Stomach cramps

  • Loss of appetite

  • Mild fever (in some cases)

The vomiting produced by gastroenteritis stomach flu usually stops within a day or two, but the diarrhea can last for several days.

Vomiting in toddlers and children normally stops within 24 hours after the symptoms start, but the diarrhea can last for another day or two. These symptoms can last for up to ten days in certain cases.

A person’s age and the type of infection can play a role in how long gastroenteritis lasts and how severe the symptoms are.

For most people with healthy immune systems, stomach flu isn't dangerous. However, if it causes dehydration and isn't treated, it can be very dangerous for newborns, toddlers, children, the sick, and the elderly.

What are the Symptoms of Stomach Flu?

Stomach flu is most commonly caused by a viral infection. There are three main viruses that are responsible for causing stomach flu.

Norovirus: this virus is the most common cause of viral gastroenteritis in adults.

Rotavirus: this type of infection is most prevalent in infants aged three to 15 months.

Adenovirus: Adenoviruses commonly affect children under two years of age.

Each of these viral infections has similar symptoms, such as:

  • Vomiting

  • Watery diarrhea

  • Nausea

  • Cramping or pain in the abdomen

  • Fever

However, there are slight differences in how long they last.

Norovirus

Norovirus is the most likely cause of gastroenteritis stomach flu, according to the Centers for Disease Control and Prevention (CDC), producing 19 to 21 million cases in the U.S. each year.

Norovirus symptoms generally last for about one to two days.

The virus is incredibly easy to spread and can survive on surfaces for days or even weeks. It can easily spread in shared enclosed places like childcare centers and nursing homes.

According to the CDC, the virus is transmissible from the day a person begins to experience symptoms until a few days after their viral gastroenteritis symptoms have eased.

This means that once a person has recognized that they have norovirus symptoms, it’s critical that they avoid close contact with people for several days.

To avoid contracting the stomach flu or to help prevent its spread, people should take the following precautions:

  • Wash hands thoroughly after using the bathroom or handling diapers, and before eating

  • Clean and disinfect surfaces that come into contact with vomit or diarrhea

  • Wash all fruits and vegetables, and cook seafood to a safe temperature

  • Wash laundry thoroughly

  • Refrain from preparing food or caring for other people when you’re sick

Rotavirus

The people most at risk of getting rotavirus include:

  • Children aged three months to three years

  • Older adults

  • Adults who work with children

  • People with a weakened immune system

Fever, stomachache, vomiting, and severe/watery diarrhea are all symptoms of the rotavirus. Symptoms usually appear two days after a person has been exposed to the virus.

It may take three to eight days for the symptoms to ease. Rotavirus is spread by fecal matter and is passed on when people don’t wash their hands after visiting the bathroom, and then touch shared objects or food.

There is a rotavirus vaccine, and doctors typically give two to three doses of the vaccine to babies between the ages of two and six months.

Adenovirus

Adenoviruses are a group of viruses that cause several illnesses, including viral gastroenteritis. They can cause upper and lower respiratory infections, brain and eye issues, and GI symptoms.

Once a person has been exposed, symptoms can occur between two days and two weeks. The typical recovery window for adults and children in good health is five to seven days, and most physicians will recommend fluid replacement and symptomatic relief as treatment.

Even if the virus no longer causes symptoms, it might still be transmissible. Adenoviruses can survive on hard surfaces for up to 30 days.

Key Point: What’s the Difference Between Viral Stomach Flu, Food Poisoning, and Seasonal Flu?

Food poisoning is commonly caused by bacteria and usually occurs within hours of ingesting contaminated food, while viral stomach flu symptoms may develop over a period of days.

Food poisoning has similar symptoms to stomach flu, but will typically last one to two days.

Seasonal flu primarily causes respiratory symptoms like a runny nose, sore throat, and a cough, as well as muscle aches and fever, and may last one to two weeks.

Viral stomach flu mainly causes gastrointestinal symptoms and lasts between two days and up to two weeks.

Is Stomach Flu Contagious?

Stomach flu can be very contagious. The amount of time you’re contagious depends on the type of infection you have.

For example, gastroenteritis caused by norovirus can become contagious as soon as the individual starts to have symptoms and can remain contagious for several days afterward.

Even after the stomach flu has passed, the virus that caused your gastroenteritis can still be contagious.

After an individual has recovered, the infectious period can continue for up to two weeks. Some of these viruses can even survive for several days to weeks on contaminated surfaces.

If a member of a household or other shared residence contracts the stomach flu, everyone in the house should regularly wash their hands, take care when preparing food, and keep all surfaces clean for the best chance of avoiding the virus.

Key Point: Seeking Care if You’re Unsure

If you're experiencing some of the symptoms, you can meet with a board-certified doctor or nurse practitioner from your smartphone, computer, or tablet. Head over to LifeMD to make your first appointment.

How Can I Treat Symptoms of Stomach Flu?

Treatment for stomach flu often doesn't require prescription medication or a healthcare professional, but rather home remedies.

Time, rest, and drinking fluids (once your body can keep them down) are the best home cures for viral gastroenteritis.

If you're unable to keep fluids down, it’s important to avoid dehydration by sucking on ice chips or popsicles, or sipping little amounts of liquid.

Water, clear broth, and drinks with electrolytes (such as Gatorade) are all good options to rehydrate and revitalize your body until you’re ready to eat solid foods again.

Keep in mind: antibiotics will only help treat stomach flu if it’s not caused by a virus, but rather by bacteria.

Treatment for Children

To aid in the recovery of infants or children with viral gastroenteritis, here are some tips for parents and caregivers:

  • Continuing formula feeding or breastfeeding infants as long as they can keep it down

  • Starting solid foods slowly with easy-to-digest foods for children

  • Avoiding giving water to a baby with the stomach flu

  • Asking a pediatrician about drinks to help with rehydration

  • Providing light fluids in the form of diluted juices, broths, and ice chips

Treatment for Adults and Older Children

When adults and older children are sick with viral gastroenteritis, they usually lose their appetite.

Even if you're hungry, don't consume a lot of food too quickly and if you’re vomiting, you should avoid eating solid foods at all.

When you feel better and your nausea and vomiting have subsided, choose foods that are easy to digest such as toast, bananas, rice, avocado, and chicken. This may help you avoid more digestive tract discomfort.

Some recovery tips include:

  • Avoiding large meals

  • Resting as much as possible

  • Drinking sports drinks and plenty of water

  • Eat softer, easy-to-digest foods

When Should I See a Doctor?

You'll probably be able to recover from a stomach flu virus without visiting a doctor, but if you’re struggling with particular symptoms, it’s best to get medication to help.

If your baby has a fever or vomits for more than a few hours, or shows other signs of stomach flu, it's advised to consult a doctor right away to avoid severe dehydration.

Here are some scenarios when you should seek medical help:

If your baby has any of the following:

  • Sunken eyes

  • Lack of a wet diaper in six hours

  • Few or no tears while crying

  • Sunken soft spot (fontanel) on the top of the head

  • Dry skin

If your toddler or child experiences:

  • A distended stomach

  • Abdominal pain

  • Severe, explosive diarrhea

  • Severe vomiting

  • 24-hour fever that is over 103°F (39.4°C)

  • Dehydration or infrequent urination

  • Blood in vomit or stool

If symptoms are severe and linger longer than three days, adults and the elderly should seek medical attention.

A doctor should be seen if there is blood in the vomit or stool. If you can't rehydrate, you should seek medical attention right away.

Signs of dehydration in adults include:

  • No perspiration

  • Dry skin

  • Little or no urination

  • Dark urine

  • Sunken eyes

  • Confusion

  • Rapid heartbeat or breathing

Where Can I Learn More about Medical Issues and Treatments?

If you are currently experiencing some of the symptoms that we’ve covered, you can stay right where you are and make a video appointment with a board-certified doctor.

Dr. Jonathan Guirguis

Dr. Guirguis attended Nova Southeastern University for medical school and stayed in South Florida to train in Internal Medicine. Born outside Chicago, he slowly made his way down south, settling in Texas with his wife and three children.

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This article is intended for informational purposes only and should not be considered medical advice. Consult a healthcare professional or call a doctor in the case of a medical emergency.

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