For more news on food safety and traceability, please see our new Special Section.

Twitter, Yelp could rival Sherlock in detecting outbreaksMany social media users share photos and comments when they have a great meal, but food safety researchers are reviewing practical applications of Twitter, Yelp and Facebook to help identify, track and issue warnings about foodborne illness outbreaks.

Foodservice operators in the Windy City are probably already aware of such an effort by the Chicago Department of Health.

The department is using an app dubbed “FoodborneChicago” to scan Twitter for key words related to foodborne illnesses, according to the department’s website.

When the app finds a tweet describing a foodborne illness incident, it generates a response from a health agency worker recommending that the person file an online report and providing a link.

The app launched in March 2013. It has catalogued more than 3,000 tweets since then, resulting in 193 reports.

When the Centers for Disease Control and Prevention reviewed the Chicago app it found those 193 reports resulted in 133 restaurants being inspected. Twenty-one were closed and 33 were ordered to resolve health violations.

The researcher, Jenine Harris of Washington University in St. Louis, reported health officials in Boston and New York City are considering similar Twitter taps.

Numbers add up

In September, researchers at Virginia Polytechnic Institute published results in the journal "Prevention Medicine" that showed a strong correlation between negative customer reviews on the website Yelp and foodborne illness outbreaks tracked by the CDC.

The study included more than 5,800 reviews of restaurants posted from 2005 through 2012.

Results showed that social media reviews could complement traditional outbreak surveillance methods by providing rapid information on suspected foodborne illnesses, the implicated foods and the restaurants involved, according to the research report.

The Virginia researchers looked at five categories of food and the rates at which Yelp reviewers reported an illness compared to the rates of CDC’s reported illness information and found very similar results:

  • Vegetables implicated in 22% of illnesses reported on Yelp, 25% from CDC;
  • Fruits and nuts implicated in 7% on Yelp, 7% from CDC;
  • Meat and poultry implicated in 32% on Yelp, 33% from CDC;
  • Dairy and eggs implicated in 23% on Yelp, 23% from CDC; and
  • Seafood implicated in 16% percent on Yelp, 12% from CDC.

Elaine Nsoesie, co-author of the study and postdoctoral research fellow at Boston Children’s Hospital and Harvard University, wrote that consumer reviews or tweets about illnesses could be an additional tool to help public health authorities detect outbreaks earlier.