Scientists are decoding the DNA of listeria in a pilot program to improve the identification and understanding of food borne illnesses. DNA decoding has long been used to diagnose rare diseases, to predict your risks of cancer, and to tell of your ancestry. But is has never been used in food safety before. DNA sequencing is now cheaper and faster than before making this a viable option.

The initial target is listeria, the third leading cause of death from food poisonining.

Listeria can be found in soil, which can lead to vegetable contamination. Animals can also be carriers. Listeria has been found in uncooked meats, uncooked vegetables, fruit such as cantaloupes,pasteurized or unpasteurized milk, foods made from milk, and processed foods. Pasteurization and sufficient cooking kill Listeria; however, contamination may occur after cooking and before packaging.

For example, meat-processing plants producing ready-to-eat foods, such as hot dogs and deli meats, must follow extensive sanitation policies and procedures to prevent Listeria contamination. Listeria monocytogenes is commonly found in soil, stream water, sewage, plants, and food. Listeria is responsible for listeriosis, a rare but potentially lethal food-borne infection. The case fatality rate for those with a severe form of infection may approach 25%. (Salmonella, in comparison, has a mortality rate estimated at less than 1%. Although Listeria monocytogenes has low infectivity, it is hardy and can grow in temperatures from 4 °C (39.2 °F) (the temperature of a refrigerator), to 37 °C (98.6 °F), (the body’s internal temperature). Listeriosis is a serious illness, and the disease may manifest as meningitis, or affect newborns due to its ability to penetrate the endothelial layer of the placenta.

This is really a new way to find and fight infections. One way to think of it is identifying a suspect by lineup or fingerprint.