Purpose: Describe the frequency and characteristics of multistate foodborne disease outbreaks.
Methods: We reviewed outbreaks reported to CDC’s Foodborne Disease Outbreak Surveillance System from 1973 through 2010. Multistate foodborne disease outbreaks were defined as ≥2 persons in multiple states with similar illnesses after exposure to a common food. We analyzed the number of illnesses, hospitalizations, and deaths; pathogens; and implicated foods.
Results: From 1973 through 2010, multistate foodborne disease outbreaks accounted for 234 (0.8%) of 27,989 total outbreaks and resulted in 3% of all outbreak-associated illnesses, 10% of hospitalizations, and 16% of deaths. On average, 2.9 multistate outbreaks occurred annually during 1973–1980, 1.4 during 1981–1990, 6.3 during 1991–2000, and 13.4 during 2001–2010. Among 230 outbreaks with a pathogen reported, most were caused by Salmonella (109; 47%) and Shiga toxin-producing Escherichia coli (60; 26%). In 174 outbreaks (74%), a food was reported and could be classified into one of 18 single food commodities; the commodities most commonly implicated were beef (39, 22%), fruits (23, 13%), and leafy vegetables (22, 13%).
Significance: From 1973 through 2010, multistate outbreaks accounted for an increasing number of foodborne disease outbreaks. Although multistate outbreaks represent only a small proportion of all outbreaks, they are responsible for a greater share of outbreak-associated hospitalizations and deaths than single state outbreaks. Knowing the pathogens and foods responsible for multistate outbreaks can help to identify important sources of food contamination and inform regulatory agencies and food industry partners to improve the safety of the food supply.