Market Overview
ABOUT FOODBORNE ILLNESS
An outbreak of foodborne illness occurs when a group of people eat or drink the same contaminated food and two or more of them develop the same illness. Many outbreaks of foodborne illness tend to be localized. A group of people may become sick after eating together at a reception or from the same local restaurant on the same day. But increasingly, outbreaks of foodborne illness are becoming more widespread, and they are affecting people in many different—and distant—locations over several weeks. As the world’s food supply becomes increasingly interconnected, the need for innovative technologies to identify foodborne pathogens before they cause illness is becoming evermore urgent.
Opportunities for Microbial Contamination
There is tremendous opportunity for foods to become contaminated while being produced and prepared because even healthy animals that are raised for food carry foodborne microbes in their intestines. The potential for meat and poultry carcasses to become contaminated during slaughter, if they come in contact with even small amounts of the animals’ intestinal contents, is significant. What’s more, a hen's ovary can be infected with some types of Salmonella, which means that a normal-looking egg may have become contaminated even before the shell formed.
Fresh fruits and vegetables also are vulnerable to foodborne microbes. If the water used for irrigation or washing is contaminated with animal manure or human sewage, fresh produce can become contaminated. Oysters and other filter-feeding shellfish can concentrate bacteria that are naturally present in sea water or other microbes that are present in human sewage dumped into the sea.
Food processing also can be a window for contamination. Foodborne microbes can be introduced from infected humans who handle the food, or by cross-contamination from another raw agricultural product. Microbes can be transferred from one food to another when using the same knife, cutting board, or other utensil to prepare both without washing the surface or utensil in between. And contact with raw foods or drippings from raw foods that contain pathogens can re-contaminate fully cooked foods.
Food storage practices also can diminish or exacerbate the chances of an outbreak. Many bacterial microbes need to multiply to a larger number before enough are present in food to cause disease. Warm moist conditions and an ample supply of nutrients can create conditions wherein a lightly contaminated food left out too long can become highly infectious.
About E. coli O157:H7, Listeria monocytogenes, Campylobacter jejuni, and Salmonella enterica
The four bacterial strains that cause the majority of non-viral foodborne illnesses are E. coli O157:H7, Listeria monocytogenes, Campylobacter jejuni, and Salmonella enterica.
E. coli O157:H7 is a bacterial pathogen that has a reservoir in cattle and other similar animals. Human illness typically follows consumption of food or water that has been contaminated with microscopic amounts of cow feces. The illness it causes is often a severe and bloody diarrhea and painful abdominal cramps, without much fever. In 3% to 5% of cases, a complication called hemolytic uremic syndrome (HUS) can occur several weeks after the initial symptoms. This severe complication includes temporary anemia, profuse bleeding, and kidney failure.
Listeria monocytogenes is found in soil and water. Animals can carry the bacterium without appearing ill and can contaminate foods of animal origin, such as meats and dairy products. When Listeria bacteria get into a food processing factory, they can live there for years, sometimes contaminating food products. The bacterium has been found in a variety of raw foods. A person with listeriosis usually has fever and muscle aches, often preceded by diarrhea or other gastrointestinal symptoms. Almost everyone who is diagnosed with listeriosis has "invasive" infection, in which the bacteria spread beyond the gastrointestinal tract. This is particularly concerning for pregnant women where infection with the bacterium can lead to miscarriage.
Campylobacter is a bacterial pathogen that causes fever, diarrhea, and abdominal cramps. It is the most commonly identified bacterial cause of diarrheal illness in the world. These bacteria live in the intestines of healthy birds, and most raw poultry meat has Campylobacter on it. Eating undercooked chicken, or other food that has been contaminated with juices dripping from raw chicken is the most frequent source of this infection.
Salmonella is also a bacterium that is widespread in the intestines of birds, reptiles and mammals. It can spread to humans via a variety of different foods of animal origin. The illness it causes, salmonellosis, typically includes fever, diarrhea and abdominal cramps. In persons with poor underlying health or weakened immune systems, it can invade the bloodstream and cause life-threatening infections.
