An Unwelcome Dinner Guest:
Avoiding Foodborne Illnesses
"Something I ate,"
or "food poisoning," or maybe just "stomach flu,"
is how we sometimes describe foodborne diseases. While symptoms
vary, nausea, vomiting, diarrhea, and fever are typical; these symptoms
usually begin several hours to a day or more after eating tainted
food. Foodborne illnesses are common. The Centers for Disease Control
and Prevention (CDC) has estimated that at least 6 million cases
occur annually in the United States; the true number may be much
larger. While most of these distressing illnesses are not life threatening,
an estimated 9,000 do lead to death each year. Some people are especially
vulnerable, including people with immune disorders (such as HIV
infection), cancer, and the elderly. Fortunately, nearly all foodborne
diseases are preventable.
There are many agents
that cause foodborne illness. The majority are bacteria, with names
like Salmonella, the E. coli O157:H7 strain, Listeria, Campylobacter,
and Vibrio. Some are viruses, including hepatitis A. Some cases
result from bacterial and other toxins, like Staphylococcus enterotoxin
or the toxin of botulism. And a small number of cases result from
parasites. Bacterial contamination in animal products accounts for
most cases of foodborne illness in the United States. Animal products
that carry a risk of illness include undercooked or raw meat, seafood,
and eggs, as well as unpasteurized milk and other dairy products.
Vegetables and fruit usually carry a much smaller risk of causing
illness, unless they are contaminated with uncooked animal products
or have been washed with unsanitary water.
Several simple measures
can greatly reduce your risk of foodborne illness:
Refrigerate or freeze poultry, meat, fish, eggs, and dairy products
products right away after purchase and keep cold until ready for
In the kitchen, keep everything clean--including the cooks
hands! Washing hands thoroughly with soap and warm water before
preparing food does make a difference. To avoid contaminating other
foods, carefully wash hands, knives, utensils, and cutting boards
immediately after handling any raw poultry, meat, or fish. Never
prepare salads or fresh produce on a cutting board that has not been
cleaned. And be sure to keep dishcloths, sponges, and kitchen towels
Thoroughly wash and rinse fresh fruits and vegetables in warm
Do not put cooked meat on an unwashed plate or platter that has
held raw meat.
Keep hot foods hot and cold foods cold. After cooking, do not let
food stand more than one or two hours before the leftovers are
refrigerated. Refrigerated leftovers should be used within three days.
And never taste food to see if it might be spoiled. This applies to
leftovers or any food in swollen, or leaky cans. If in doubt, throw it
Unfortunately, it is popular to serve some foods without adequate
cooking. We recommend special precautions with the following:
Avoid rare hamburger. With proper refrigeration, bacterial
contamination usually does not penetrate far into steaks or other
large pieces of meat. Cooking the outer part of the steak kills these
bacteria, even if the deeper, uncontaminated parts are still rare. But
with ground meat such as hamburger it is different. Hamburger can be
contaminated with bacteria mixed throughout meat, and if the hamburger
is served rare, bacteria in the center may survive to cause disease. A
number of fatal illnesses from the E. coli O157:H7 strain have been
attributed to contaminated hamburger served rare.
Avoid raw oysters. Restricting raw oyster consumption to those
harvested from state-inspected and approved oyster beds may reduce the
risk of foodborne illness, but does not eliminate that risk. Oysters
that are sautééed, baked or boiled until plump are much safer.
Avoid raw fish or fish served rare. In addition to bacterial
illness, fish may occasionally transmit parasites. Seafood should be
Eggs should be cooked until the white is firm and the yolk begins
to harden. Avoid foods containing raw eggs, such as homemade ice
cream, cookie dough, cake batter, mayonnaise, and eggnog, because they
carry a Salmonella risk. Commercial products are usually safer because
the eggs have been pasteurized.
Finally, avoid unpasteurized milk and dairy products.
We have a few parting tips:
Outbreaks of severe, sometimes fatal illness from E. coli O157 have
increased in recent years. While usually associated with undercooked
meat, especially rare hamburger, some cases of this illness have also
been traced to unpasteurized apple cider and to contaminated alfalfa
Don't thaw meat and other frozen foods at room temperature.
Instead, move them from the freezer to the refrigerator for a day or
When it comes to food safety, remember that the saying "rules are
made to be broken" does not apply!