Gastroenteritis Fact Sheet
What is gastroenteritis?
Inflammation of the stomach and intestines that often results in diarrhea and/or vomiting. Diarrhea is usually mild and brief and occurs when bowel movements are less formed and more watery.
When diarrhea or vomiting is caused by an infection it is often called "acute gastroenteritis", or "stomach flu".
Infection is usually caused by viruses (e.g. rotavirus or norovirus). It can also be caused by bacteria (e.g. shigella, E.coli, salmonella, campylobacter and yersinia) or parasites (e.g. giardia).
Diarrhea or vomiting may also be caused by dietary changes, medications, or other causes.
How is gastroenteritis spread?
Germs can be found in the stool or vomit of infected people and spread easily to others:
- by eating food or drinking liquid that is contaminated
- if they touch their mouth after touching contaminated surfaces or objects
- when in direct contact with an infected person who has symptoms
Contact with animals (e.g. pets, farm animals, reptiles) can also spread germs.
What are the symptoms of gastroenteritis?
More bowel movements than usual and stools that are less formed and more watery.
Other symptoms may include fever, chills, loss of appetite, nausea, vomiting, stomach cramps, muscle aches, fatigue, blood and/or mucous in the stool.
Symptom onset and length of time it is considered contagious varies, depending on the cause.
How is gastroenteritis treated?
Drink plenty of fluids to avoid dehydration.
Seek medical attention if any concerns.
How is gastroenteritis prevented?
Those with diarrhea and/or vomiting should not prepare meals or feed others.
Clean and disinfect washrooms and common touched surfaces (e.g. doorknobs, taps, counter and tabletops, light switches, etc.) more frequently.
Hand washing is the most important way to stop the spread of infectious gastroenteritis. Wash hands often with soap and water for at least 15-20 seconds or use alcohol-based hand sanitizer, especially:
- after diaper changes, toileting or using the bathroom
- after handling pets, animals, their food or treats, or their waste
- for children who have diarrhea, especially if they are still in diapers
Safe food handling:
- Wash fruits and vegetables, especially if eating raw.
- Separate raw food from cooked food.
- Wash hands, utensils, chopping boards, and surfaces carefully after handling raw meat to prevent cross-contamination.
- Cook meat, poultry, and eggs thoroughly. See Health Canada's website for Safe cooking temperatures for more information on food safety and safe internal cooking temperatures.
- Eat foods soon after they are cooked.
- Keep hot foods hot and cold foods cold.
- Reheat cooked foods adequately.
- Store cooked foods appropriately and store foods in closed containers in a safe place.
- Always use water that has been treated or tested.
Where can I get more information about gastroenteritis?
Contact the Communicable Disease Control (CDC) Program at 705-474-1400, or toll-free at 1-800-563-2808, ext. 5229 or email us at cdc@healthunit.ca.
References:
- Canadian Paediatric Society. Caring for Kids. (2018). Dehydration and diarrhea in children: Prevention and treatment.
- American Academy of Pediatrics (2023). Managing Infectious Diseases in Child Care and Schools: A Quick Reference Guide, 6th edition. Shope, T. R. and Hashikawa, A.N.
- Public Health Agency of Canada. (2022). Norovirus: Symptoms and treatment.
- American Academy of Pediatrics. Child care settings. Kimberlin, D.W., Banerjee, R., Barnett, E.D., Lynfield, R., Sawyer, M.H., EDs. Red Book: 2024-2027 Report of the Committee on Infectious Diseases, 33rd ed. Itasca, IL: Amercian Academy of Pediatrics: 2024, pp.145-157
Created: May 2026, by CDC