Gastroenteritis

Diagnosis

Gastroenteritis can usually be diagnosed based on symptoms, a history of exposure, and a physical exam. Your physician will suspect gastroenteritis if you have had a few days of gastrointestinal upset. Information about exposure to people with similar symptoms at home or in the workplace, having recently eaten unusual-tasting or otherwise suspicious food, or having recently been on a camping trip or having traveled outside of the U.S. can help with the diagnosis. The physician will perform a physical exam to rule out urgent problems such as appendicitis, and will check for signs of dehydration.

Laboratory testing is only occasionally needed. If symptoms are unusually severe or last more than a week, the physician may order lab tests. Stools can be directly examined under the microscope and cultured for various bacteria and parasites.

Prevention and Screening

Hand washing is the best protection against spreading viral gastroenteritis. Food handlers, health care personnel, and child care workers should be especially thorough in washing hands after using the bathroom, diapering, or handling bedpans. Promptly disinfecting contaminated surfaces using household chlorine bleach—based cleaners is essential in institutional settings. In households where someone is sick, avoid sharing hand towels, and promptly launder any soiled linens.

Observe safe food-handling procedures to avoid food poisoning, both at home and in group settings. With reasonable care, most food-borne cases of gastroenteritis can be avoided. Take particular precautions with foods that have the greatest danger of spoiling, including meat, seafood, mayonnaise, eggs, and milk products, especially when preparing picnics or large events.

• Wash hands before handling food and after touching meat, fish, or eggs.
• Keep work areas clean. Never use cutting surfaces, plates, or utensils that have touched raw meat for anything else until thoroughly washed.
• Cook meat thoroughly. Never partially cook meat, then leave to reheat later.
• Keep food in coolers for as long as possible at picnics. Foods kept out at room temperature for longer than two hours should be discarded.
• Throw out any food that you are unsure about.

For further information about the safe cooking and handling of foods, call USDA's Meat and Poultry Hotline at (800) 535-4555.

Take precautions when going to a less-developed country or on a camping trip. Before traveling to another country, find out if the water is safe to drink. If not, drink only bottled or boiled water. While hot foods should be safe, avoid uncooked vegetables or fruits that you have not peeled yourself. High-risk individuals who travel to underdeveloped countries may wish to take antibiotics as a precaution against gastroenteritis. These include people with AIDS, inflammatory bowel disease, or those who regularly use insulin (to control diabetes, for example) or a medication like cimetidine (Tagamet), which alters the acid environment of the stomach.

Before wilderness camping, learn about various water-purification methods that are available. These include filtration devices or tablets that can be added to water. Do not assume that clear mountain streams are safe.