Evaluation and Investigation
Prompt and thorough laboratory evaluation of cases and suspected foods is essential. Single cases of foodborne disease are difficult to identify unless, as in botulism, there is a distinctive clinical syndrome. Although foodborne disease may be one of the most common causes of acute illness, many cases and outbreaks go unrecognized and unreported. The following links aid in the evaluation of potential foodborne disease outbreaks.
- Investigations Operations Manual. U.S. Food and Drug Administration (FDA).
- Foodborne Diseases Active Surveillance Network (FoodNet). Centers for Disease Control and Prevention (CDC). Provides a foundation for food safety policy and prevention efforts. It estimates the number of foodborne illnesses, monitors trends in incidence of specific foodborne illnesses over time, attributes illnesses to specific foods and settings, and disseminates this information.
- Food Protection Program. Massachusetts Health and Human Services.
Report foodborne disease epidemics to local health authorities. Take the following steps when conducting an epidemiological investigation:
- Review reported cases to determine the time and place of exposure and the population at risk.
- Obtain a complete list of foods served.
- Hold and refrigerate all food still available.
- Collect samples of vomit and feces for laboratory testing and inform the laboratory of suspected contaminants.
- Compare illness rates for specific foods eaten and those not eaten. The suspected food will usually have the highest associated illness rates. Most of the sick will have eaten the suspected food.
- Investigate the source of the suspected food and methods of preparation and storage.
- Look for possible sources of contamination and inadequate refrigeration or heating.
- Submit samples of suspected food for laboratory testing.
- Evaluate food handlers for sources of infections, including culture of lesions, nasal swabs, and feces where appropriate.