Foodborne Illness Surveillance
Foodborne illnesses are one of the most commonly reported infectious diseases. Foodborne illnesses are monitored through several surveillance systems including reportable disease surveillance, syndromic surveillance, and consumer complaints.
In addition to investigating sporadic cases of foodborne illness, the Bureau of Infectious Disease Control investigates several foodborne outbreaks (when it is determined that 2 or more people have a similar illness from eating a common food) each year. These outbreaks are most commonly caused by Salmonella or Norovirus and are often related to poor food preparation or storage practices.
What is a Foodborne Disease?
A foodborne illness or disease is a gastrointestinal illness caused by eating contaminated food.
Foodborne diseases generally fall into one of the following three categories:
- foodborne intoxications in which a food is contaminated with a toxin-producing bacteria and the toxin causes illness when eaten or after being produced in the gastrointestinal tract. Contamination from toxin-producing fish, shellfish, and plants can cause intoxications as well.
- foodborne infection in which the bacteria itself is ingested and causes illness or infection with a virus or parasite causes illness.
- foodborne poisoning in which the food is contaminated with a chemical such as a heavy metal or organic compound.
Symptoms generally involve vomiting or diarrhea and depend on the specific organism, toxin, or poison that caused the illness. The amount of time that passes between eating the food and getting sick also depends on the specific organism, toxin or poison and can range from a couple hours (i.e. Staphylococcus aureus toxin) to weeks (i.e. hepatitis A virus).
Food Safety Tips
In general, foodborne illnesses are preventable if safe food handling practices are followed. Below are some facts and tips to teach you the basics of food safety (adapted from the North Carolina Department of Agriculture and Consumer Services).
1. Keep hot foods hot.
If a food is cooked and put out to serve, food should be kept hot if it is not going to be eaten right away. If food is cooled in the refrigerator, it should be cooled quickly in a shallow container. Perishable food should not be kept at temperatures between 40°F and 140°F for more than 2 hours. Bacteria can grow well at these temperatures and may grow to levels that could cause illness.
2. Keep cold foods cold.
Cold salads, lunchmeats, dairy products and other foods that require refrigeration should be kept cold (below 40°F). Bacteria may be able to grow to dangerous levels at warmer temperatures.
3. Wash hands properly.
Our hands naturally carry bacteria on them. If we transfer those bacteria to food, the food is a good place for those bacteria to grow. Foods contain a certain amount of bacteria on them as well, especially raw foods. It is important not to let the bacteria from raw foods stay on your hands where you may transfer them to your mouth or other foods. Be sure to wash your hands using the technique below:
- Wet your hands with warm water. Add soap and rub your hands to a soapy lather.
- Wash the front and back of your hands, between your fingers and under your nails. Count to 20, or sing "Happy Birthday" twice will take about 20 seconds).
- Rinse well.
- Dry hands with a clean paper towel.
- Turn off faucet with a new clean paper towel.
4. Don't cross contaminate.
Don't allow juices associated with raw meat and poultry to contaminate other areas of your kitchen where they can be transferred to other foods and to your hands. Use separate cutting boards for meats and vegetables and never place cooked food on a plate that was used to hold raw meat, poultry, eggs, or seafood.
5. Thaw foods safely.
Frozen raw meat and poultry should not be thawed by leaving them on the counter at room temperature. The proper way to thaw such products is to thaw them in the refrigerator, in a microwave oven, or sitting in cold water.
6. Wash fresh fruits and vegetables thoroughly.
Because fresh fruits and vegetable are grown outside, they may come in contact with a wide range of bacteria. Most of these bacteria are harmless, but it is important to realize that fresh fruits and vegetables should be washed thoroughly under running water before eating them.
7. Keep eggs refrigerated and don't eat raw eggs
Eggs may contain the bacteria Salmonella. It is important not to leave eggs at room temperature or the Salmonella can multiply and grow. Eggs should also be cooked thoroughly before eating. This means no eating runny yolks or cookie or cake batters made with raw eggs.
8. Cook ground beef thoroughly.
E. coli O157:H7, Salmonella and other harmful bacteria may be present in raw ground meat. Hamburgers and other ground meat products should be cooked thoroughly to kill bacteria. Ground beef must reach an internal temperature of 160°F to ensure that bacteria have been killed. The interior of the meat may turn brown before this temperature is reached, making it look like the hamburger is done, but you cannot assure it's safety until the temperature reaches 160°F.
9. When in doubt, throw it out.
Don't taste food you think may be spoiled. If you are uncertain whether food is still safe to eat, do not eat it. Even reheating foods cannot destroy the toxins of some bacteria if a food has been handled incorrectly. Don't eat canned food if the can is bulging or looks like it has had a leak.