More than half of Salmonella outbreaks caused by single serotype
From 1998 to 2008, more than 80% of Salmonella outbreaks were attributed to eggs or poultry and more than 50% of outbreaks were attributed to plant commodities, according to study results published recently.
“Salmonella enterica is estimated to cause 1.2 million illnesses each year in the United States and to be the leading cause of hospitalizations and deaths from foodborne disease,” researchers wrote in Emerging Infectious Diseases. “Because of the major public health role of Salmonella infections, the US Department of Health and Human Services has made decreasing the nationwide incidence of these infections by 25%, a Healthy People 2020 national goal.”
Researchers reviewed all reported of foodborne outbreaks from Salmonella infections to the Foodborne Disease Outbreak Surveillance System (FDOSS) from 1998 to 2009.
During the time period, 1,491 outbreaks of Salmonella infections were reported to FDOSS, 80% of which were caused by a single serotype. Of the single-serotype outbreaks, 50% had an implicated food and 34% were attributed to a single food commodity.
Among the 34%, 47 serotypes were reported, the four most common caused 66% of the outbreaks: Enteritidis (36%), Typhimurium (14%), Newport (10%), and Heidelburg (6%). Eggs were the most common food commodity (28%), following by chicken (16%); pork (9%); beef (8%); fruit (8%); and turkey (7%).
“The results of our analysis can provide guidance to investigators when forming hypotheses about contaminated food sources during outbreak investigations, and in suggesting the likely contaminated ingredient in outbreaks associated with foods containing ingredients from multiple commodities,” researchers wrote. “Investigators should also remain alert to uncommon or novel food vehicles, which are regularly being identified. Armed with knowledge of serotype-food commodity associations, public health officials may be able to more quickly form hypotheses, identify likely sources of contamination, and prevent illnesses.”
Disclosure: The researchers report no relevant financial disclosures.