Investigating Foodborne Outbreaks
In the United States, millions of foodborne illnesses occur each year. A foodborne illness is caused by eating or drinking a contaminated food or beverage. When two or more people get the same illness from the same contaminated food or drink, the event is called a foodborne outbreak. Illnesses that are not part of outbreaks are called "sporadic." Public health officials investigate outbreaks to control them, so more people do not get sick in the outbreak, and to learn how to prevent similar outbreaks from happening in the future. Here, we explain how the public health community detects, investigates, and controls foodborne outbreaks.
Foodborne illnesses are caused by pathogens and toxins (chemicals). Pathogens are germs, such as bacteria, viruses, and parasites, that can cause illness. More than 250 pathogens and toxins are known to cause foodborne illness. Nearly all of them can cause an outbreak.
Many types of foods can become contaminated. Some of the foods that have been linked to outbreaks are eggs, fish and shellfish, meat, nuts, poultry, raw (unpasteurized) milk, and raw fruits and vegetables.
The Food Production Chain
It takes several steps to get food from the farm or fishery to the dining table. We call these steps the food production chain. Contamination can occur at any point along the chain—during production, processing, distribution, or preparation.
Size and Extent of Foodborne Outbreaks
Like any fresh produce that is consumed raw or lightly cooked, sprouts carry a risk of foodborne illness. Unlike other fresh produce, seeds and beans need warm and humid conditions to sprout and grow. These conditions are also ideal for the growth of bacteria, including Salmonella, Listeria, and E. coli.
Key Players in Foodborne Outbreak Response
Public health agencies that identify and investigate foodborne illnesses operate on several levels. Which agency or agencies participate in an investigation depends on the size and scope of the outbreak. Sometimes one agency starts an investigation and then calls on other agencies as more illnesses are reported across county or state lines.
Step-by-Step Guide to Investigating Foodborne Outbreaks
Preventing Future Outbreaks
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