Listeria account for less than 1 percent of reported
cases of bacterial foodborne infection. Most identified cases can be traced
back to contaminated food and the attack rate can be 50-100%. The lucky victims
have subclinical infections.
Common symptoms include
fever, watery diarrhea, nausea, vomiting, headache, and pains in joints and
muscles.The typical duration of symptoms is two days or less, and recovery is
generally complete. Invasive infection seems to be rare, with the risk being
greatest in immunocompromised, pregnant, or older adult patients. Listerial
infection in pregnant women can lead to fetal death, premature birth, or
infected newborns.
The
following represents a compilation of the precautions recommended by the
Centers for Disease Control and Prevention:
●Do not drink raw (unpasteurized) milk or eat foods
that contain unpasteurized milk.
●Wash raw vegetables thoroughly before eating.
●Keep the refrigerator temperature at 40ºF (4.4ºC)
or lower; the freezer at 0ºF (-17.8ºC) or lower.
●Eat precooked, perishable, or ready-to-eat food as
soon as possible.
●Keep raw meat, fish, and poultry separate from
other food that will not be cooked and from cooked foods and ready-to-eat
foods.
●Wash hands, knives, and cutting boards after
handling uncooked food.
●Thoroughly cook raw food from animal sources to a
safe internal temperature: ground beef 160ºF (71ºC), chicken 170ºF (77ºC),
turkey 180ºF (82ºC), and pork 160ºF (71ºC).
The following
additional recommendations were made for individuals at high risk such as
pregnant women and those who are immunocompromised:
●Do not eat hot dogs, luncheon
meats, bologna, or other delicatessen meats unless they are reheated until
steaming hot; avoid the use of microwave ovens for reheating such meats since
uneven cooking may occur.
●Avoid contamination of utensils
and food preparation surfaces with fluid from packages containing hot dogs,
luncheon meats, delicatessen meats, raw meat, chicken, turkey, or seafood.
Handwashing is also important immediately after handling of any of these
products.
●Do not eat prepackaged salads
containing ham, chicken, egg, tuna, or seafood.
●Do not eat soft cheeses such as
feta, Brie, and Camembert, blue-veined cheeses, or Mexican-style cheeses such
as queso blanco, queso fresco, and Panela, unless they have labels that clearly
state they are made from pasteurized milk.
●Do not eat refrigerated pâtés or
meat spreads. However, canned or shelf-stable products are safe and can be
eaten by pregnant women.
●Do not eat refrigerated smoked
seafood, unless it is cooked as in a casserole. Refrigerated smoked seafood,
such as salmon, trout, whitefish, cod, tuna, or mackerel, is most often labeled
as "nova-style," "lox," "kippered,"
"smoked," or "jerky." Such fish products are typically
found in the refrigerator section or sold at deli counters of grocery stores
and delicatessens. However, canned or shelf-stable smoked seafood may be eaten.
The
CDC has a comprehensive discussion.
