Epidemiology of foodborne illnesses

Humans are the ultimate bioassay for low-level or sporadic contamination of our food supply. Epidemiologic methods of foodborne disease surveillance are powerful tools because they take advantage of events that are occurring throughout the population. This population-based lens, focused by advances in molecular subtyping and information technology available to public health laboratories, is particularly well suited to dealing with foodborne diseases associated with mass-produced and widely distributed food products. Whole-genome sequencing (WGS) is becoming the standard for public health surveillance. It offers greater sensitivity for outbreak detection and greater specificity for outbreak investigation than previous methods of analysis. WGS links between cases and foods or environmental samples will require exposure assessment. Public health officials will be challenged to provide the epidemiologic resources to investigate and solve the anticipated growth in small outbreaks. Better outbreak investigation methods, including environmental assessments, will provide more useful data to evaluate the effectiveness of food safety policies and improve food attribution models. Improving the science base for policy development should lead to more effective food control activities. Since national food supplies are rapidly becoming global in origin, the need for an international system for foodborne disease surveillance exists as well. Because foodborne disease problems imported into one country may represent disease problems endemic to the food-producing country, growing awareness of these problems could stimulate investment in interventions that improve public health in both countries.