By Kate Griesmann

Food-borne illnesses are a common malady that effect one in six Americans each year.

Salmonella bacteria are the second leading cause of food-borne illness (norovirus is the first), and an outbreak can set off a firestorm of recalls and reminders about safe food handling practices.

Duke physicians Christopher Woods, MD, MPH, and Nancy McGreal, MD, explain what salmonella is and what you can do to prevent these bacteria from wreaking havoc on your digestive system.

Bacteria Among Us

“Salmonella bacteria are a frequent cause of food-borne disease outbreaks because they colonize animals and can contaminate both animal products and other agricultural products,” says Woods, a Duke physician specializing in infectious diseases.

While children are most likely to get salmonella infection -- also called salmonellosis -- the elderly, infants, individuals with sickle cell disease, and those with compromised immune systems are also at high risk of infection.

People often contract salmonellosis by eating something contaminated by a strain of salmonella bacteria. Contaminated foods (usually meat or poultry) look and smell normal, making it difficult to know there is a problem until it’s too late.

Though salmonella bacteria are often grouped together under one name, there are about 2,000 different strains, or serotypes. “The most common situation we consider is egg-associated salmonellosis, caused by Salmonella enterica serotype Enteritidis,” says Woods. “But, there are a number of other important serotypes.”

Some strains of salmonella are associated with enteric (typhoid) fever, a potentially lethal disease that is rarely seen in the United States, but common in many places worldwide.

In addition to ingesting the bacteria, people can be exposed by touching young birds and some reptiles (such as lizards, turtles, and snakes) that may have the bacteria on them.

Getting the Best of a Stomach Bug

The symptoms of salmonellosis -- abdominal pain or cramping, diarrhea, and fever -- resemble those of many gastrointestinal illnesses. Symptoms will normally begin 12 to 72 hours after being exposed to the bacteria and last for several days.

Though a recent CDC study found that salmonella was the leading cause of food-borne illness-related deaths, most people will recover fully after four to seven days without any medical treatment.

Staying well hydrated is a vital part of the recovery, as dehydration is common during salmonellosis. For some people with severe dehydration, intravenous fluids may be recommended.

“Anti-diarrheal therapies are not recommended in cases of a bacterial intestinal infection, as they may make things worse,” says McGreal, a Duke gastroenterologist.

In serious cases, the infection may enter the bloodstream, making antibiotics necessary. “Salmonella infection during pregnancy is taken seriously because it can have significant consequences for a growing fetus, including death,” McGreal says.

Keeping Illness at Bay

Good hand washing is key to prevention when it comes to salmonella. People should wash their hands:

• Anytime they may have contact with feces, such as changing a diaper or cleaning up pet waste
• After touching turtles, lizards, snakes, birds, or their environment
• After handling raw eggs or meat or unpasteurized milk

Particular care should be taken in homes with susceptible individuals such as infants, elderly, and immunocompromised individuals.

Several widespread salmonella outbreaks have taken place in recent years, causing recalls of foods ranging from eggs to tomatoes to peanut butter. These recalls should not be taken lightly both physicians agree.

“People should stay abreast of the news and heed the advice of the CDC, FDA, and Department of Agriculture when such warnings are issued,” McGreal says.

A useful site for keeping track of food-related alerts is Foodsafety.gov, which posts food recall information as well as numerous safety tips.