Study Findings Using NEARS Data

Read food safety study findings and recommendations related to outbreaks reported to the National Environmental Assessment Reporting System (NEARS).

Preventing Outbreaks
Clostridium Perfringens

African Guy Suffering From Abdominal Pain Lying On Sofa Indoor

Outbreak investigators reported three underlying root causes that precede C. perfringens outbreaks. These causes are linked with people, processes, and equipment.

Root Causes of Clostridium perfringens Outbreaks


restaurant store front

Understanding practices linked with smaller and shorter outbreaks helps restaurants take steps to help control and prevent norovirus outbreaks.

Norovirus Outbreaks and Restaurant Practices

Improving Outbreak Investigations
Contributing Factors

African Guy Suffering From Abdominal Pain Lying On Sofa Indoor

Timely and complete outbreak assessments are important to identifying contributing factors.

Factors that Contribute to Outbreaks of Foodborne Illness

Environmental Assessments

Female investigator is speaking with a chef in a kitchen.

An environmental assessment provides information that can stop ongoing outbreaks and prevent them in the future. But health department investigators do not always conduct environmental assessments of outbreaks.

Why Investigators Did or Did Not Do Environmental Assessments for Restaurant Outbreaks

Outbreak Investigations

Waiter serving a table in busy restaurant

Learn about the outbreaks and gaps we found in retail food safety practices and outbreak investigations. 

Outbreak Investigations of Restaurants, 2014-2016

Successful Investigations

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Foodborne outbreak investigations are more often successful when they include data collected through environmental health assessment, epidemiologic investigation, and laboratory testing.

Traits of Successful Foodborne Outbreak Investigations

More Findings

Explore more food safety outbreak findings using other data.

Restaurant Inspections

Sign with the letter A

Studies found posting health department restaurant inspection scores at restaurants and using letter grades for restaurant inspection results are linked with fewer foodborne outbreaks and could lead to safer restaurants.

Outbreak Rates and Restaurant Inspection Practices