Health Library

Health Library Explorer
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z Listings
Click a letter to see a list of conditions beginning with that letter.
Click 'Topic Index' to return to the index for the current topic.
Click 'Library Index' to return to the listing of all topics.

Bacterial Gastroenteritis

Gastroenteritis is often called the stomach flu. It's an inflammation of the GI (gastrointestinal) tract, which includes your stomach and intestines. Most cases of gastroenteritis are caused by viruses. Bacterial gastroenteritis (caused by bacteria) is less common but can cause more severe symptoms. It can even cause death. This sheet tells you more about bacterial gastroenteritis, how it can be prevented, and how to care for it.

How does bacterial gastroenteritis spread?

  • Contaminated food or water. You’re most likely to get gastroenteritis by having food or water containing harmful bacteria (such as salmonella, Campylobacter, and E. coli). Food can be contaminated when food handlers don’t wash their hands. Or when food isn’t stored, handled, or cooked correctly.

  • Fecal-oral route. People with bacterial gastroenteritis have harmful bacteria in their stool. When they don’t wash their hands well after using the bathroom, they can spread the germs to objects. If you touch the same objects, you can pick up the germs on your hands and transfer them to your mouth.

What are the symptoms of bacterial gastroenteritis?

Many kinds of bacteria cause gastroenteritis. So symptoms can vary. In some types of gastroenteritis, symptoms start quickly. In others, they don’t appear for 24 to 48 hours. Symptoms can range from mild to severe and may include:

  • Watery diarrhea

  • Upset stomach (nausea) and vomiting

  • Fever and chills

  • Belly (abdominal) pain

  • Blood in the stool (in severe cases)

How is bacterial gastroenteritis diagnosed?

Your healthcare provider will take a complete health history. Be sure to mention any recent trips and what you ate before you became ill. Keep in mind that symptoms may not appear for 1 or 2 days after you're infected. You may be asked to give a stool sample. This is sent to a lab for testing. Don’t forget to check with your provider or hospital emergency room to learn the test results. In some cases, you'll be asked to see your provider for follow-up care.

How is bacterial gastroenteritis treated?

  • Bacterial gastroenteritis often goes away without treatment. In some cases, symptoms are gone in 1or 2 days. In others, symptoms linger for weeks. In certain cases, it can take months for your bowels to return to normal.

  • Replacing fluids lost through diarrhea and vomiting is important for a full recovery. If you're very dehydrated, you may need fluids through an IV (intravenous) line in the hospital.

  • Medicines that slow diarrhea may be prescribed. It depends on what your provider thinks is causing your symptoms. But these medicines can make your illness last longer.

  • Your provider will prescribe antibiotics only if your symptoms are caused by certain types of bacteria or your symptoms are severe.

  • You may be admitted to the hospital if your symptoms are very bad.

Easing symptoms of bacterial gastroenteritis

In most cases, bacterial gastroenteritis is treated at home. To ease symptoms and prevent complications:

  • Get plenty of rest.

  • Drink lots of liquids to replace water lost through diarrhea and vomiting. Plain water, clear soups, and electrolyte solutions are best. (You can find electrolyte solutions in most pharmacies.) Don't have fizzy (carbonated) drinks, alcohol, coffee, tea, colas, milk, and fruit juice. These can make symptoms worse. If nausea and vomiting make it hard for you to drink, try sucking on ice chips.

  • Eat according to your healthcare provider’s instructions.

  • Until the diarrhea clears up, don't eat fruit or any dairy except yogurt. They can make diarrhea worse.

Preventing bacterial gastroenteritis at home

  • Use good hand hygiene. Always wash your hands well before and after making food, and after handling raw meat and poultry. Also wash them after using the bathroom, changing diapers, or caring for someone who's ill. See the "Tips for good handwashing" section below.

  • Wash all raw fruits and vegetables (even packaged ones) with a scrub brush or vegetable wash.

  • Have a cutting board that you only use for meat. Wash all cutting boards and utensils in hot, soapy water after each use. Clean kitchen counters with bleach or disinfectant after each use.

  • Cook meats to a safe temperature to kill bacteria that may be present in the meat. Use a food thermometer when cooking. Follow these temperature guidelines:

    • Cook ground meat (beef, veal, pork, lamb) and meat mixtures to at least 160°F (71°C).

    • Cook fresh beef, veal, lamb, and pork (steak, roasts, chops) to at least 145°F (63°C).

    • Cook poultry (including ground turkey and chicken) to an internal temperature of at least 165°F (74°C).

  • Wear gloves when handling a sick person's clothes, bed linens, diapers, or towels. Discard the gloves after each use. Then scrub your hands as described below in Tips for good handwashing. Wash bed linens and other personal items separately in hot water with detergent and liquid bleach.

Preventing gastroenteritis in healthcare settings

Many hospitals and nursing homes take these steps to help prevent the spread of gastroenteritis:

  • Handwashing. Healthcare workers wash their hands well with soap and water or use an alcohol-based hand cleaner before and after touching someone. They also wash their hands after touching any surface that may be contaminated.

  • Protective clothing. Healthcare workers wear gloves and sometimes gowns when working with people who have gastroenteritis. They remove these items before leaving the room.

  • Private rooms. People with bacterial gastroenteritis are placed in private rooms. This is to prevent the spread of infection.

  • Safe food handling. Kitchen workers wash their hands often, cook foods correctly, and disinfect all work surfaces.

Tips for good handwashing

Closeup of hands being washed with soap and water.
Washing your hands carefully and often is one of the best ways to prevent the spread of bacteria that cause gastroenteritis.

Wash your hands often. Always wash them after using the bathroom, playing with pets, and before eating or making food. Clean the whole hand, under your nails, between your fingers, and up the wrists:

  • Wash for at least 20 seconds with clean, running water. Don’t just wipe. Scrub well. Hum the Happy Birthday song twice if you need a timer.

  • Rinse. Let the water run down your fingers, not up your wrists.

  • Dry your hands well using a disposable paper towel. Use a paper towel to turn off the faucet and open the door.

Using alcohol-based hand gels

When soap and water are not readily available, an alcohol-based hand gel containing at least 60% alcohol is a good choice.

  • Squeeze about 1 tablespoon of gel into the palm of your hand.

  • Rub your hands together briskly. Clean the backs of your hands, the palms, between your fingers, and up the wrists.

  • Rub until the gel is gone and your hands are completely dry.

When to call your healthcare provider

Call your healthcare provider right away if you have any of these:

  • Your symptoms get worse

  • Blood in your stool or your stools look black

  • You have signs of dehydration, such as a dry mouth, intense thirst, confusion, and little or no urine

  • A fever of 100.4°F ( 38°C) or higher, or as advised by your provider

Online Medical Reviewer: Chris Southard RN
Online Medical Reviewer: Rita Sather RN
Online Medical Reviewer: Sabrina Felson MD
Date Last Reviewed: 3/1/2024
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Contact Our Health Professionals
Follow Us