(HealthDay News) — Foodborne illness outbreaks most commonly involve norovirus, according to research published in the June 2 issue of the US Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.

Erin D. Moritz, PhD, from the CDC in Atlanta, and colleagues summarized environmental health data collected during foodborne illness outbreak investigations and reported to the National Environmental Assessment Reporting System (NEARS) during 2017 to 2019.

A total of 800 foodborne illness outbreaks associated with 875 retail food establishments were reported to NEARS during 2017 to 2019 by 25 state and local health departments. The researchers found that 69.4% of the outbreaks with a confirmed or suspected agent involved norovirus and Salmonella, accounting for 47.0 and 18.6%, respectively. Of the outbreaks with identified contributing factors, about 40 percent had at least one factor associated with food contamination by an ill or infectious food worker. In 679 outbreaks, an establishment manager was interviewed; 91.7% of those said that their establishment had a policy requiring food workers to notify the manager when they were ill; 66.0 percent of these policies were written. Only 23.0% said that all five illness symptoms workers needed to notify managers about were listed (vomiting, diarrhea, jaundice, sore throat with fever, and lesion with pus).

“The findings in this report can help public health authorities and the retail food establishment industry develop data-driven, effective approaches to preventing foodborne illness outbreaks,” the authors write.

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