Stomach Flu Symptoms


Stomach flu is also known as viral gastroenteritis, which refers to the inflammation of the gastrointestinal tract. Viral gastroenteritis may affect both the stomach and the intestine. It mainly damages the internal lining of the stomach and the intestine. However, viral gastroenteritis is not caused by the influenza virus, though it is commonly called stomach flu.

Apart from viral infections, gastroenteritis can be caused by bacterial infections, excessive intake of certain medications like antibiotics and non-steroidal anti-inflammatory drugs, and food-borne illnesses. The bacterial infections of the intestine can be caused by SalmonellaShigellaStaphylococcusCampylobacter jejuniClostridiumEscherichia coliYersinia pestisVibrio cholerae, etc.


It is primarily caused by five types of viruses – rotavirus, adenovirus, astrovirus, norovirus, and calicivirus. Caliciviruses can cause intestinal infection in people of any age group, while rotavirus is the most important cause of stomach flu in infants, especially those in the age group of 3 to 15 months. In general, children under the age 5 years can get infected by this virus.

Adenoviruses can also be an important cause of gastroenteritis in children under the age of 2 years. In adults, viral gastroenteritis is more commonly caused by norovirus, while the astrovirus mainly affects the elderly and the children. People usually contract this viral infection by eating or drinking contaminated food and water. The consumption of raw or undercooked food can also cause gastroenteritis.

Signs of Stomach Flu

The signs and symptoms of viral gastroenteritis can be mild or severe, and they usually appear within 1 to 3 days following the infection. The symptoms of viral gastroenteritis are more or less similar in both adults and children. These symptoms can last for about 1 to 10 days. The most common symptoms of this condition are:

  • Watery diarrhea
  • Low-grade fever
  • Nausea
  • Vomiting
  • Abdominal pain and cramps
  • Bloating
  • Loss of appetite
  • Headaches
  • Weakness and fatigue
  • Lethargy

If the infection is not treated on time, it can worsen and produce some serious symptoms. For example, diarrhea and vomiting can cause a significant loss of body fluid, which can result in dehydration. Dehydration can cause increased thirst, sunken eyes, dry mouth, decreased urine output, and lightheadedness. In addition to these, some other serious symptoms of gastroenteritis are:

  • Persistent vomiting
  • Presence of blood in stool and vomit
  • High-grade fever
  • Abdominal swelling

The symptoms of viral gastroenteritis that are more commonly observed in children are:

  • Diarrhea
  • Low-grade fever with chills
  • Vomiting
  • Dehydration
  • Loss of appetite or poor feeding
  • Pale or cold and clammy skin
  • Sunken eyeballs
  • Sunken fontanelle in infants

Stomach Flu Treatment

Gastroenteritis caused by bacteria can be treated with antibiotics, but antibiotics are ineffective in treating viral gastroenteritis. There is no specific treatment plan for this condition. Certain medications are available that can control the symptoms like diarrhea and vomiting. Dehydration can be prevented by drinking plenty of fluid and electrolyte solutions.

Children affected by this condition should be given oral rehydration solutions. During an episode of gastroenteritis, certain foods like dairy products, sugary foods, caffeine, alcohol, and fatty and greasy foods should be avoided. Bland and easily digestible foods, such as rice, bananas, potatoes, and toast can be consumed during this period.

If the symptoms persist for more than a day or two, then consider to seek medical help. To prevent this condition, it is essential to practice good personal hygiene. Washing the hands with soap and water before eating a meal, and after visiting the toilet, can help avoid this viral infection to a great extent. Alcohol-based hand sanitizers can also be used for disinfecting the hands. On the other hand, sharing food and utensils with others, and eating undercooked food, especially undercooked meat and fish, should be avoided. Gastroenteritis caused by rotavirus can be prevented to a great extent with vaccinations.