×

Please Remove Adblock
Adverts are the main source of Revenue for DoveMed. Please remove adblock to help us create the best medical content found on the Internet.

Viral Gastroenteritis

Last updated Jan. 9, 2019

Approved by: Maulik P. Purohit MD MPH

Viral Gastroenteritis, also commonly referred to as Stomach Flu, is an infection of the gastrointestinal tract, which is caused by contaminated food and water.


What are the other Names for this Condition? (Also known as/Synonyms)

  • Gastric Flu due to a Virus
  • Norwalk Virus Infection
  • Stomach Flu due to a Virus

What is Viral Gastroenteritis? (Definition/Background Information)

  • Viral Gastroenteritis, also commonly referred to as Stomach Flu, is an infection of the gastrointestinal tract, which is caused by contaminated food and water
  • Severe abdominal cramps, nausea, vomiting, and diarrhea, are characteristics of this viral infection. Occasionally, mild to moderate fevers may also occur
  • Individuals, who ingest contaminated food or water, acquire Viral Gastroenteritis. It can also be contracted from someone, who is infected, through direct contact
  • There are very few complications resulting from Viral Gastroenteritis and a full recovery is generally observed

Who gets Viral Gastroenteritis? (Age and Sex Distribution)

Viral Gastroenteritis is observed in males and females of all age groups. Different types of Viral Gastroenteritis may occur in certain specific people demographics and this is based on the virus type. The virus types include:

  • Adenovirus
  • Astrovirus
  • Norovirus
  • Norwalk virus
  • Rotavirus

Adenovirus and Astrovirus are types of viruses that predominantly affect younger individuals, even though older individuals may occasionally contract the virus. Norovirus and Norwalk virus are types of viruses that usually affect young adults. Rotavirus causes a type of Viral Gastroenteritis that mainly affects infants and children, who are less than 5 years old.

What are the Risk Factors for Viral Gastroenteritis? (Predisposing Factors)

Viral Gastroenteritis general risk factors include:

  • Young children
  • Elderly adults
  • Overcrowded living conditions
  • Individuals with weak immune system, such as those with AIDS, individuals who have undergone chemotherapy for malignancies, or any clinical condition resulting in decreased immunity

Some risk factors are specific to particular virus types.The time of the year is also important, because certain virus types are seasonally active. For example, infections from rotavirus and norovirus are more commonly seen between October and April.

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Viral Gastroenteritis? (Etiology)

Viral Gastroenteritis is usually acquired through contaminated food or water. Sharing of utensils and towels used by infected individuals can also result in transmission of the infection.

There are a number of virus types can cause Viral Gastroenteritis, which include:

  • Adenovirus
  • Astrovirus
  • Norovirus
  • Norwalk virus
  • Rotavirus

Occasionally, the stomach condition can also be caused by poliovirus.

What are the Signs and Symptoms of Viral Gastroenteritis?

The signs of Viral Gastroenteritis include:

  • Watery diarrhea containing blood
  • Cramping pain in the abdominal region
  • Nausea, vomiting
  • Mild to moderate fevers
  • Non-specific body aches, headache
  • Change in bowel habits

The symptoms of Viral Gastroenteritis usually last for 72 hours. Rarely, do the symptoms prolong for more than a week. It is important to note this type of gastroenteritis, will usually not cause blood in the vomit.

The signs and symptoms of Viral Gastroenteritis may sometimes be similar to a more severe infection called Bacterial Gastroenteritis. It is important to seek prompt medical attention, if the symptoms do not improve, or if the following scenario is observed:

  • Severe vomiting for 24 hours
  • Blood in vomit
  • Signs of dehydration are noted, which may include:
    • Dry mouth
    • Extreme tiredness
    • Excessive thirst
    • Lack of urine production; a marked decrease in urine production
  • Blood in stools
  • Severe fever over 104°F, with chills and shivering/shaking

In infants and children, it is very important to seek medical attention, if the following symptoms occur:

  • Fever greater than 102°F
  • Excessive crying, crying without tears
  • Blood in vomit
  • Blood in stools
  • Decreased urine output; the child has not wet a diaper within a time frame of 6 hours
  • A decreased or complete loss of alertness
  • Increased irritability
  • Increased sleepiness or drowsiness

How is Viral Gastroenteritis Diagnosed?

  • A case of Gastroenteritis can usually be diagnosed by a thorough medical examination that includes evaluating a patient’s clinical history and physical examination
  • A laboratory test called ‘rapid stools’ can help detect rotavirus or norovirus infection
  • In case of severe dehydration, a complete blood count with a complete metabolic panel analysis, can reveal electrolyte imbalances

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Viral Gastroenteritis?

A majority of Viral Gastroenteritis cases are mild. Individuals with this infection will usually have a full recovery, without any kind of complications. However, the following may be observed, in severe cases:

  • Severe dehydration
  • Excessive vomiting and diarrhea can result in a loss of body fluids and salts, causing severe muscle cramps
  • Severe muscle cramping may even result in acute kidney failure

How is Viral Gastroenteritis Treated?

  • Normally, there is no specific treatment for Viral Gastroenteritis
  • The treatment is usually supportive, which includes fluid restoration and the use of over-the-counter medications, in order to reduce a fever
  • Antibiotics are not effective against viruses and should not be used in confirmed cases of Viral Gastroenteritis

How can Viral Gastroenteritis be Prevented?

There are various methods to decrease the chances of contracting Viral Gastroenteritis infection, which are:

  • Avoiding undercooked meat and fish products
  • Wash fruits and vegetables thoroughly before consuming them
  • Drink from safe water sources; avoid contaminated ice cubes
  • Wash hands regularly,especially if you are around an infected individual
  • Avoid sharing of any utensils and towels with affected individuals. This can help decrease the transmission of infection to a healthy individual
  • There are a variety of different vaccines that exist against various types of Viral Gastroenteritis. Vaccinations will help prevent specific types of Viral Gastroenteritis
  • If you are traveling to endemic areas with established cases of Viral Gastroenteritis; then, your physician may recommend suitable vaccination types

What is the Prognosis of Viral Gastroenteritis? (Outcomes/Resolutions)

  • Majority of Viral Gastroenteritis are mild and they resolve on their own. Most individuals recover from this infection, without any complications and have an excellent prognosis
  • If the symptoms are severe and prolonged, then it may result in permanent damage to various parts of the organs in the body. However, complications from Viral Gastroenteritis are generally rare

Additional and Relevant Useful Information for Viral Gastroenteritis:

  • In many geographical regions of the world (mainly the lesser industrialized nations), where the healthcare system lacks the kind of preparation and resources needed to treat dehydration, caused by vomiting and diarrhea; the mortality rates due to Gastroenteritis is substantial
  • Stomach Flu is not caused by the influenza (flu) virus

What are some Useful Resources for Additional Information?


References and Information Sources used for the Article:


Helpful Peer-Reviewed Medical Articles:


Reviewed and Approved by a member of the DoveMed Editorial Board
First uploaded: Sept. 20, 2013
Last updated: Jan. 9, 2019