Listeria bacteria can lead to serious health issues for vulnerable populations. (Getty Images)

Talk about unappetizing: In just the past month or so, I’ve seen news reports on disease outbreaks caused by tainted tomatoes, contaminated chicken, cilantro and nuts, and food-poisoned pastries — pastries, people!

Clearly, food-borne illness is a major problem in this country. In fact, this year alone, roughly one in six Americans will get sick from eating meat, poultry, produce or some other fare contaminated with a bad bug, according to the Centers for Disease Control and Prevention.

If you are slightly compulsive, as I am, perhaps you’ve been wondering where the biggest risks in the supermarket lie. Researchers at the Emerging Pathogens Institute at the University of Florida have ranked the top 10 microorganism-food combinations that raise the most concerns from a public-health standpoint.

The most troublesome combination is campylobacter-laden poultry, which sickens more than 600,000 people annually, resulting in nearly 7,000 hospitalizations. Next on the list, which was based on a decade’s worth of data about disease outbreaks, deaths and costs and a peer-reviewed survey of experts, were pork contaminated with toxoplasma and deli meats tainted with listeria.

The most problematic pathogen was salmonella, which appeared four times — in combination with poultry, complex foods (i.e., non-meat dishes composed of multiple ingredients), produce and eggs — and caused just over 250 deaths and nearly 16,000 hospitalizations.

“For the top 10, all together, we’re talking about $8 billion, just in cost of illness, each year,” says the institute’s director, Glenn Morris, an infectious-disease specialist. “People don’t need to be overly paranoid, but it’s important to be aware that the way our food is being produced leaves open the possibility of these serious food-borne illnesses. Everyone should know the risks, because they are very real.”

Indeed, many experts believe this new study is merely the tip of the iceberg. “In the majority of cases, people generally don’t go to the doctor; they just self-treat at home for a few days,” says Jessica Leibler, a research scientist at the George Washington University School of Public Health and Health Services who specializes in infectious diseases in food systems.

In fact, most food poisoning incidents are mild, perhaps causing a day or two of such symptoms as diarrhea or vomiting. “But they can make you absolutely miserable,” says pediatrician and epidemiologist Lynn Goldman, dean of the GWU public-health school. And there can be far more serious, even deadly complications, especially for vulnerable populations such as pregnant women, children, the elderly and those with compromised immune systems. For example, in rare cases campylobacter causes paralysis, and one particularly toxic type of E. coli bacteria can result in severe kidney damage; both toxoplasmosis and listeria can lead to serious health issues for expectant mothers, including miscarriage, premature labor, birth defects and stillbirth.

Experts say some simple steps can help reduce the likelihood of contracting a food-borne illness in your own kitchen, starting with a vigilant approach to food preparation. “I think you definitely need to consider that anything you buy at the grocery store today . . . could have a pathogen in it or on it,” says Goldman.

A few other tips:

- This one’s a bit of a no-brainer, but always wash your hands with soap and warm water before and after handling ingredients.

- Use a quality instant-read thermometer to ensure that meat is cooked thoroughly. Goldman suggests sticking to the USDA-recommended safe cooking temperatures for meat, fish and egg dishes (available at, “which are a little bit higher than a lot of cookbooks recommend.”

- Ban bloody burgers. “You really shouldn’t ever be eating hamburgers rare or medium rare” because of the risk that the toxic strain of E. coli, which “can contaminate the surface of meat,” might get mixed in throughout ground beef, says Morris. (On the other hand, he says it’s okay to eat a good steak rare, because searing it kills surface bacteria.)

- Use separate cutting boards — and also knives — for meat and produce. Otherwise, you might transfer harmful bacteria from raw meat, poultry or fish onto salad greens or other food that isn’t going to be cooked, says gastroenterologist Robynne Chutkan, an assistant professor at the Georgetown University Medical Center.

- Refrigerate or freeze leftovers as soon as possible, before microorganisms can multiply. This is especially important in picnic season, warns Goldman, who says that any grub that’s been outside for more than two hours on a warm day should be trashed.

- Finally, before dining out, consider checking an establishment’s health inspection history through local governments’ Web sites, many of which will have such information.

Still, there’s only so much that any of us can do to avoid food-borne illnesses. “Unfortunately, there are a lot of opportunities for contamination along the chain from farm to fork, for all foods,’ says Morris of the Emerging Pathogens Institute. He points out that all the good hygiene in the world won’t protect you from disease-causing microorganisms found in fare that’s already fully cooked when you buy it, such as deli meats or soft cheeses, or pathogens that get inside produce through tainted water or soil and can’t be washed away.

“The major problems are upstream — outside of the supermarket, outside of restaurants, outside of our own kitchens — and have to do with how meat and all our food is produced, in this country,” says GWU’s Leibler, who, along with Morris and all of the others I spoke with, stresses the need for better industry practices and more stringent government monitoring and regulation.

“At the end of the day, you can make sure you cook everything thoroughly and be ultra-careful about cross-contamination, but this issue won’t go away just by keeping your kitchen clean, or being vegetarian, or even purchasing local meat or vegetables and buying organics,” she says. “This is a problem for everyone who eats.”