Bacterial gastroenteritis can affect one person or a group of people who all ate the same food. It is commonly called food poisoning. It often occurs after eating at picnics, school cafeterias, large social gatherings, or restaurants.
The germs may get into your food (called contamination) in many ways:
Meat or poultry may come into contact with bacteria when the animal is processed.
Water that is used during growing or shipping may contain animal or human waste.
Improper food handling or preparation may occur in grocery stores, restaurants, or homes.
Food poisoning often occurs from eating or drinking:
Food prepared by someone who did not wash their hands properly
Food prepared using unclean cooking utensils, cutting boards, or other tools
Dairy products or food containing mayonnaise (such as coleslaw or potato salad) that have been out of the refrigerator too long
Frozen or refrigerated foods that are not stored at the proper temperature or are not reheated properly
Raw fish or oysters
Raw fruits or vegetables that have not been washed well
Raw vegetable or fruit juices and dairy products (look for the word "pasteurized" to make sure the food is safe to eat or drink)
Undercooked meats or eggs
Water from a well or stream, or city or town water that has not been treated
Many different types of bacteria can cause bacterial gastroenteritis, including:
If you have diarrhea and are unable to drink or keep down fluids because of nausea or vomiting, you may need fluids through a vein (IV). Young children may be at extra risk from getting dehydrated.
If you take diuretics ("water pills"), talk to your health care provider. You may need to stop taking the diuretic while you have diarrhea. Never stop or change your medicines without first talking to your health care provider.
Antibiotics are not prescribed very often for most common types of bacterial gastroenteritis. If diarrhea is very severe or you have a weakened immune system, antibiotics may be needed.
You can buy medicines at the drugstore that can help stop or slow diarrhea.
Do not use these medicines without talking to your health care provider if you have bloody diarrhea, a fever, or the diarrhea is severe.
Do not give these medicines to children.
Most people get better in a few days without treatment.
Certain rare types of E. coli can cause severe anemia, gastrointestinal bleeding or even kidney failure.
When to Contact a Medical Professional
Call your health care provider if you have:
Blood or pus in your stools, or your stool is black
Diarrhea with a fever above 101°F (100.4°F in children)
Recently traveled to a foreign country and developed diarrhea
Stomach pain that does not go away after a bowel movement
Symptoms of dehydration (thirst, dizziness, light-headedness)
Also call your doctor if:
The diarrhea gets worse or does not get better in 2 days for an infant or child, or 5 days for adults
A child over 3 months old has been vomiting for more than 12 hours; in younger babies, call as soon as vomiting or diarrhea begins
Sodha SV, Griffin PM, Hughes JM. Foodborne Diseases. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2009:chap 99.
Craig SA. Gastroenteritis. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Mosby Elsevier; 2013:chap 94.
Bhutta ZA. Acute Gastroenteritis in Children. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 332.
Todd Eisner, MD, Private practice specializing in Gastroenterology, Boca Raton, FL. Affiliate Assistant Professor, Florida Atlantic University School of Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.