Tracking Foodborne Disease
Routine monitoring of important diseases by public health departments is called disease surveillance. Each state decides which diseases are to be under surveillance in that state.
- In most states, diagnosed cases of salmonellosis, E coli O157: H7 and other serious infections are routinely reported to the health department.
- The county reports them to the state health department, which reports them to CDC. Tens of thousands of cases of these "notifiable diseases" are reported every year.
- However, most foodborne infections go undiagnosed and unreported, either because the ill person does not see a doctor, or the doctor does not make a specific diagnosis. Also, infections with some microbes, such as norovirus, are not reportable in the first place, unless they are associated with a recognized outbreak.
Special Surveillance System
To get more information about infections that might be diagnosed but not reported, the Centers for Disease Control and Prevention (CDC) developed a special surveillance system called FoodNet.
- FoodNet is a collaborative program among CDC, 10 state health departments, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA-FSIS), and the Food and Drug Administration (FDA).
- It provides the best available information about specific foodborne infections in the United States, and summarizes them in an annual report.
- FoodNet has conducted active, population-based surveillance for laboratory-confirmed infections caused by Campylobacter, Listeria, Salmonella, STEC O157, Shigella, Vibrio, and Yersinia since 1996; Cryptosporidium and Cyclospora since 1997; and STEC non-O157 since 2000.
- The surveillance area includes 15% of the United States population (46 million persons).
In addition to tracking the number of reported cases of individual infections, states also collect information about foodborne outbreaks, and report a summary of that information to CDC. More than 1,000 foodborne outbreaks investigated by local and state health departments are reported each year. This includes information about many diseases that are not notifiable and thus are not under individual surveillance, so it provides some useful general information about foodborne diseases.