What is stomach flu (viral gastroenteritis)?
Stomach flu is a viral infection that affects the stomach and small intestine. It is also called viral gastroenteritis. Viral gastroenteritis is a common infection of the stomach and intestines that results in vomiting and diarrhoea. It can be caused by a number of different viruses, such as Rotavirus and Norovirus (previously known as Norwalk-like virus). There are many
other causes of non-viral gastroenteritis including bacteria, toxins, parasites, and some non-infectious diseases.
Viral gastroenteritis is a highly contagious leading cause of illness, but it seldom lasts for longer than 72 hours. It is characterized by a sudden onset of loose, watery bowel movements, which may or may not be accompanied by fever, chills, weakness, muscles aching, stomach or abdominal pain, nausea, vomiting or gas.
Many types of viruses can cause gastroenteritis but the most common are Rotavirus and Norwalk virus. Rotavirus is the leading cause of gastroenteritis in children and can also occur in adults exposed to children with the virus. Norwalk virus causes group-related or institutional diarrhea with peak frequency during the winter. Norwalk-like viruses are common in school-age children. These viruses are often found in contaminated food or drinking water. The viruses cause about 40% of group-related diarrheal illnesses. They affect older children and adults and are more frequent during the winter months. Symptoms appear within 4 to 48 hours after exposure to the contaminated food or water. The viruses are usually spread by the fecal-oral route. Rotavirus causes severe gastroenteritis in infants and young children. Severe dehydration and death can occur in the young age group. It is responsible for up to 50% of the hospitalizations of children with diarrhea. Outbreaks may also occur in geriatric settings such as nursing homes. Usually, by the age of 3, most children have acquired an antibody to the virus.
The main symptoms of viral gastroenteritis are vomiting and watery diarrhoea. Other symptoms may include nausea, fever, abdominal pain, headache, and muscle aches. Dehydration can follow. Symptoms can take between one and three days to develop and usually last between one and two days, sometimes longer.
The objective of treatment is to replace fluids and electrolytes (salt and minerals) lost by diarrhea. Antibiotic therapy is not effective in viral illness. Antidiarrheal medications are generally not given, as they may prolong the infectious process. Self-care measures to avoid dehydration include drinking electrolyte solutions (available over-the-counter) to replace fluids lost by diarrhea. People with diarrhea who are unable to take fluids by mouth because of nausea may need intravenous fluids, especially in small children. People taking diuretics need to be cautious with diarrhea, and may need to stop taking the diuretic during the acute episode. (Always consult with the health care provider before stopping a prescribed medication!)
Do not give anti-diarrheal medications to children unless directed to do so by a health care provider. Since the risk of dehydration is greater in infants and young children, parents should closely monitor the number of wet diapers changed per day when the child is sick. Electrolyte and fluid replacement solutions for children are available in food and drug stores. Jell-O water, soda and plain water do not replace electrolytes the child needs when dehydrated from vomiting or diarrhea. Children with diarrhea often benefit from dietary modifications until the diarrhea subsides.
More information on gastroenteritis
What is gastroenteritis? - Gastroenteritis is an inflammation of the stomach and intestine resulting in diarrhea, with vomiting and cramps when irritation is excessive.
What causes gastroenteritis? - The most common cause of gastroenteritis is viral infection. Gastroenteritis arises from ingestion of viruses, certain bacteria, or parasites.
What is stomach flu (viral gastroenteritis)? - Stomach flu (viral gastroenteritis) is a viral infection that affects the stomach and small intestine. It is also called viral gastroenteritis.
What is bacterial gastroenteritis? - Bacterial gastroenteritis is an inflammation of the stomach and intestines caused by bacteria or bacterial toxins.
What is eosinophilic gastroenteritis? - Eosinophilic gastroenteritis is a rare disease in which the lining of the stomach, small intestines and large intestines become inflitrated with eosinophilis.
What are the symptoms of gastroenteritis? - The main symptoms of gastroenteritis include poor feeding in infants, vomiting and fever, usually rapidly followed by diarrhoea.
How is gastroenteritis diagnosed? - The symptoms of gastroenteritis are usually enough to identify the illness. However, if identification of the infectious agent is required.
What're the treatments for gastroenteritis? - Symptoms of uncomplicated gastroenteritis can be relieved with adjustments in diet, herbal remedies, and homeopathy.
How is gastroenteritis prevented? - If the gastroenteritis is caused by a virus, it probably cannot be prevented. There are few steps that can be taken to avoid gastroenteritis.