What is gastroenteritis?

Gastroenteritis Definition

Gastroenteritis is an infectious disease that can be caused by a range of bacteria, viruses and other pathogens. The stomach and small intestine become inflamed and infected  Many people refer to this foodborne illness a the stomach flu or coming down with a stomach bug but it is not classified as a flu.

Gastroenteritis Symptoms

Symptoms of gastroenteritis typically show up 12 to 72 hours after the initial contact with infected substances. Symptoms usually last about a week if the cause is a virus. If the cause is a bacterial infection, the illness may last up to several weeks.

  • Diarrhea
  • Vomiting
  • Fever
  • Tiredness
  • Muscle aches
  • Abdominal pain
  • Dehydration
  • Dry mouth and skin
  • Bacterial infections may also cause bloody stools

Causes of Gastroenteritis

  • Viruses
      • Viruses such as norovirus among adults and rotavirus among children are two of the leading causes of foodborne illnesses in the U.S.
      • People may be carriers of these viruses even after symptoms have disappeared.
      • Small breakouts can occur when there is a high concentration of people in local areas such cruise ships and hospitals.
  • Bacteria
      • Campylobacter jejuni is the cause of most U.S. cases of bacterial gastroenteritis and half of those cases are linked to poultry.
      • Other common bacteria include E. Coli, Salmonella, and Listeria
  • Parasites
      • Gia Giardia, Entamoeba histolytica, and Cryptosporidium spp species of parasites are among the most common causes of gastroenteritis. However, in developed countries, the majority of cases are not caused by parasites.
  • Contamination
      • Each of the above foodborne illness sources can be transmitted through humans and some animals. Animal feces and intestines carry many bacteria and can contaminate produce that is nurtured with manure. Water can also carry bacteria that causes gastroenteritis.
  • Non-Infectious
    • Individuals who are lactose intolerant, have celiac disease, and Crohn’s disease may also exhibit gastroenteritis symptoms due to some foods not settling well. If you get food poisoning often, it may be beneficial to get tested by a doctor for potential allergies to certain foods.

Treatment for Gastroenteritis

Depending on the cause of the illness, treatment will vary. For example, most bacterial infections can be treated with antibiotics if necessary. However, doctors advise that patients who have gastrointestinal problems like diarrhea and vomiting should drink plenty of water and other fluids to avoid dehydration.

Prevention of Gastroenteritis

Most causes of foodborne illness are linked to poor hygiene or mishandling of food. Follow the simple checklist below to avoid becoming infected.

  • Wash hands properly when handling food
  • Know the minimum internal temperatures for poultry and meats
  • Avoid eating dairy products made with unpasteurized, raw milk
  • Wash hands thoroughly after being around animals
  • Properly store foods before prep and after cooking and cooling in appropriate temperatures


Gastroenteritis is a disease. For more information on the bacterial or viral causes of this foodborne illness, please visit our Food Poisoning page.