Top food-poisoning culprits
Every year, about one in six Americans contracts a foodborne illness, according to the Centers for Disease Control and Prevention. Food-poisoning symptoms are severe enough to send 128,000 people to the hospital and to kill 3,000 annually. Bacteria, viruses, chemicals and parasites can all be the culprits.
Foodborne illness happens year-round. In summer, hot days and picnics pose extra hazards. In fall and winter, holiday potlucks combine food-handling mysteries with temperature-control issues. “Most bacteria can multiply in 30 minutes,” says Marlene Janes, associate professor at the Louisiana State University Food Science Department. Bacteria love heat, whether from summer sun or your cozy house in winter. If you suddenly have abdominal pain, chills, vomiting, diarrhea and/or fever, it could be that potluck cole slaw or an undercooked Thanksgiving turkey.
Fortunately, consumers can do a lot to minimize their chance of coming down with a foodborne illness, Janes says.
-- By Teresa Bergen for MSN Healthy Living
Nearly half of foodborne illnesses stem from produce, especially leafy greens, according to the CDC. This is bad news for Monica Theis and other dietitians trying to promote healthful eating.
“I strongly support more consumption of fresh fruits and vegetables,” says Theis, a food-safety specialist at the University of Wisconsin at Madison. “A challenge with fresh produce is we don’t always cook it. So we don’t have the advantage of that kill step.” She recommends buying from a reputable source, keeping produce refrigerated and rinsing it in cold water before eating. If you buy pre-washed spinach, don’t wash it again at home, because you might introduce new contaminants.
Pathogens often enter the produce from untreated water supplies. Many small farmers use water from wells, rivers and creeks to irrigate their crops, Janes says. The Food and Drug Administration’s 2013 Food Safety Modernization Act will impose higher standards for water, soil and sanitation on farms.
Milk took a huge leap in safety when chemist Louis Pasteur developed the pasteurization process in the 1880s. But dairy products still manage to be the runner-up in transmitting the most cases of foodborne illnesses. Despite more than 100 years of science behind pasteurization, some natural-food proponents tout the superiority of raw milk. Raw, unpasteurized dairy products are more likely to contain E. coli, listeria and salmonella than pasteurized products. Young children, pregnant women, elderly people and those with compromised immune systems are especially at risk.
Listeria has shown up recently in artisanal cheese from Wisconsin, as well as in cantaloupe and processed meat. “One challenge with listeria is it grows at refrigerated temperatures,” Theis says, “so it’s a pretty scary bug.” Listeria is one of the more severe foodborne illnesses and may result in death.
Contaminated poultry causes about 19 percent of deaths from foodborne illnesses, more than any other food product, according to the CDC. Listeria and salmonella are the most frequent causes. Campylobacter, a diarrhea-causing bacteria that lives in the intestines of birds, can make many people sick with fever and cramping but is seldom serious.
Getting sick from poultry is almost entirely preventable. Theis, who consults on food safety in institutional settings, says checking the temperature of chicken with a kitchen thermometer is standard practice. “It seems a little perhaps clinical to do it in the home, but if you want to be sure, there you go,” she says. Cook your poultry to 165 degrees and you’ll kill the micro-organisms.
To avoid cross-contamination, wash your cutting board with dish detergent and rinse in hot water before switching from chopping poultry to vegetables. To be extra careful, sanitize with a diluted chlorine solution.
Some types of salmonella infect hen ovaries, so that even an egg that appears normal may not be. “One in 20,000 eggs is contaminated with salmonella,” Theis says. “But you don’t want to be the one that gets it.”
The 1976 movie “Rocky” inspired fans to copy the young boxer’s raw-egg smoothie. That’s a no-no, Janes says, adding that eating raw cookie dough made with eggs is also contraindicated for people wanting to remain healthy.
Avoiding salmonella from eggs is simple. Choose eggs with intact shells. Refrigerate them as soon as possible. Cook eggs – and foods containing eggs – thoroughly.
Fish and shellfish
Shellfish are filter feeders, meaning they eat by straining food particles from the water. Over time, they accumulate whatever pathogens are in the sea. Fish and shellfish account for about 6 percent of foodborne illnesses and 6 percent of deaths from foodborne illnesses, according to the CDC. Grouper, tuna, salmon, shrimp and lobster are especially likely to convey illnesses to diners. In some cases, the water was contaminated by norovirus or Vibrio bacteria. In others, naturally occuring toxins in the fish cause illness. For the safest dinner, buy fresh fish that’s clear-eyed and not too fishy-smelling. Take frozen fish straight from the store to your home freezer. The FDA recommends cooking fish and shellfish to an internal temperature of 145 degrees.
Oysters are also filter feeders. Janes, who lives in Louisiana, gets a firsthand look at the local oyster-fishing industry and its battles with norovirus. “My lab is trying to better understand how the oysters get contaminated,” she says. Improper sewage dumping and lack of sufficient sanitation are the likeliest culprits. Oysters also concentrate Vibrio bacteria from sea water. Some types of Vibrio bacteria are particularly harmful to people with liver damage.
“As long as they’re cooked, it’s OK,” Janes says. “If you eat them raw, you’re taking a chance.” What about the famous aphrodisiacal properties of oysters? Don’t be fooled. “That’s just a way to promote them,” she says.
Clostridium botulinum grows in soil and other places where there’s no oxygen, forming heat-resistant spores. Potatoes, which grow underground, can come into contact with these spores. So be careful when baking potatoes. “If they’re wrapped in tin foil, it creates a nice environment for spores to survive,” Janes says. Botulism is one of the less common types of foodborne illness, but it’s one of the most lethal toxins known to people, Janes says.
To avoid spore growth, don’t leave foil-wrapped baked potatoes sitting out at room temperature. Eat the potatoes within two hours of cooking. If you need to save them for later, keep them at 140 degrees or hotter, or refrigerate the baked potatoes within two hours of cooking.
In the early 1900s, insufficiently cooked canned foods led to big botulism outbreaks. Government regulators cracked down on the canning industry and the botulism problem was mostly eliminated. However, home canning still results in occasional cases of botulism.
Symptoms of botulism appear 18 hours to 10 days after eating the bad food. They include blurred vision, slurred speech, drooping eyelids and weak muscles. Untreated, victims may be paralyzed or die. If caught early enough, doctors can treat botulism with an anti-toxin made from horses.
“I would not ever discourage someone from home canning,” Theis says, “but I would definitely encourage them to know that they’re doing. Contact a local expert if you’ve never canned before.”
Raw meat may contain salmonella, listeria, E. coli or parasites. Cooking destroys these organisms, but you must handle and store meat properly to avoid recontamination. Foods that combine parts of many animals are especially hazardous, as one contaminated animal can ruin the whole batch. For example, hundreds of different cows might contribute to one hamburger.
Cook hamburgers and meatloaf to 160 degrees, and whole cuts to 145. If you’re grilling, allow meat to rest for five minutes after removing it from the grill. This lets the meat finish cooking.
Bovine spongiform encephalopathy, also known as mad-cow disease, has killed more than 200 people in the U.K. but only four in the United States, as of 2012. People who eat cows that were fed the brains and spinal cords of other cows can develop a lethal variant of the disease. Cooking does not help.