by Edward Paredez, MD, Scripps Memorial Hospital La Jolla
What do spinach, ground beef, cilantro, frosting, peanut butter, instant oatmeal and chocolate chip cookie dough have in common? Of course they’re all foods, but they’ve also all been making the news lately as potential sources of illness-causing bacteria. From salmonella in peanuts to E. coli in hamburger meat, a variety of bacteria have been finding their way into our food supply, leaving behind a long list of symptoms ranging from abdominal pain, vomiting, and watery or bloody diarrhea to more serious, or even fatal, complications.
Microbial foodborne illness, more commonly known as food poisoning, affects more than 75 million people every year in the United States and causes approximately 5,000 deaths. We’re not the only country with this problem; foodborne illness is seen all over the world, and our global food supply means that food grown or processed in other countries, for example, could infect people in the United States and vice versa.
We know of more than 200 different microbes known to cause food poisoning. Here are a few of the most common and the symptoms usually associated with them:
- Salmonella is the main cause of foodborne illness in the United States. Infection usually occurs after eating food contaminated with animal feces, usually caused by meat or poultry that has not been thoroughly cooked or has been cross-contaminated with bacteria from other foods.
- E. coli O157:H7 is another major food poisoning culprit. E. coli infection can occur when food or water becomes contaminated with fecal bacteria. A small percentage of infected people, especially children and those with weakened immune systems, develop a serious type of kidney failure called hemolytic uremic syndrome as a result of the infection; symptoms can include fever, headache, and confusion.
- Campylobacter bacteria are commonly found in poultry and may contaminate 70 to 80 percent of raw chicken. It can be passed on to people by handling contaminated poultry or consuming undercooked meat, milk, eggs or untreated water. The most common symptoms include abdominal cramping and profuse diarrhea, which may be bloody. In some cases, these symptoms may be preceded by a high fever, body aches, delirium, and chills.
- Cyclospora cayetanensis, a parasite, has been linked with food poisoning outbreaks associated with imported fresh fruits and vegetables imported to the U.S.; most likely, the parasite spread to the produce through a contaminated water source.
- Clostridium dificile or “C Diff” colitis is an increasingly common and possibly severe infectious colitis from the environment that typically affects persons who have recently taken antibiotics for other infections such as urinary tract infections
In most cases, foodborne illnesses last only a few days, and most people recover without complications. Staying hydrated is extremely important, since so much fluid is lost through diarrhea and, in some cases, vomiting. Instead of drinking sports drinks or soda, which contain high amounts of sugar that can worsen diarrhea, consider oral rehydration solutions available from your pharmacy. In addition to drinking plenty of fluids, eat small, low-fat meals and get adequate rest to help your body recover. Anti-diarrheal medications may be used for mild to moderate symptoms but may prolong certain infections such as salmonella.
If your symptoms are severe or do not improve in a few days, you develop a fever or bleeding, or have other concerns, consult your doctor. It’s also a good idea to notify a doctor if the infected person is a child, elderly or has a weakened immune system or underlying medical condition. In some cases, prescription medications or IV fluids may be recommended.
In many cases, you can greatly reduce the risk of food poisoning by following these basic preventive measures:
- Wash raw fruits and vegetables thoroughly before eating.
- Keep the refrigerator temperature below 40ºF (4.4ºC) and the freezer at 0ºF (-17.8ºC) or lower.
- Use precooked, perishable, or ready-to-eat food as soon as possible.
- Wash hands, knives, and cutting boards after handling uncooked food, including meat, fruits, vegetables and eggs. Keep raw meat, fish, and poultry separate from other food.
- Thoroughly cook raw meat to a safe internal temperature: ground beef 160ºF (71ºC); chicken 170ºF (77ºC); turkey 180ºF (82ºC); pork 160ºF (71ºC).
- Cook seafood thoroughly. Raw fish that is labeled “sushi-grade” or “sashimi-grade” has been frozen, which kills some (but not all) harmful microorganisms.
- Cook eggs until the yolk is firm.
- Refrigerate foods promptly. Never leave cooked foods at room temperature for more than two hours.
- Sign up for e-mail notices about food recalls from the FDA
If you are infected, wash your hands frequently and stay home from work or school until you have recovered—as long as diarrhea or vomiting continues, you may still be able to spread the infection.
Edward Paredez is a gastroenterologist at Scripps Memorial Hospital La Jolla. “To Your Health” is brought to you by the physicians and health care professionals at Scripps La Jolla. For more information or to make an appointment, call 1-800-SCRIPPS.
Media Contact: Lisa Ohmstede