The New York City Department of Health and Mental Hygiene (DOHMH) has reportedly partnered with the restaurant review Website Yelp to help health officials discover foodborne illness outbreaks and the restaurants allegedly responsible for them.

While investigating an outbreak of gastrointestinal disease associated with a particular restaurant, DOHMH officials had apparently noted that patrons had reported illnesses on Yelp that had not been reported to DOHMH. To explore the potential of using Yelp to identify unreported outbreaks, DOHMH then collaborated with Columbia University and Yelp on a pilot project to identify restaurant reviews on Yelp that referred to foodborne illness. Researchers analyzed approximately 294,000 Yelp restaurant reviews from July 2012 to March 2013, using a software program developed specifically for the project.

According to the Centers for Disease Control and Prevention, which published a report detailing the project, the program identified 893 reviews that required further evaluation by a foodborne disease epidemiologist. Of the 893 reviews, 499 (56 percent) described an event consistent with foodborne illness (e.g., patrons reported diarrhea or vomiting after their meal), and 468 described an illness within four weeks of the review or did not provide a timeframe. Apparently only 3 percent of the illnesses referred to in the 468 reviews had also been reported to DOHMH during the same period. Closer examination revealed that 129 of the 468 reviews required further investigation, resulting in telephone interviews with 27 reviewers. From the 27 interviews, three previously unreported restaurant-related outbreaks linked to 16 illnesses met DOHMH outbreak investigation criteria, and the three restaurants were charged with multiple food-handling violations.

DOHMH reportedly plans to continue the project and refine it by (i) shortening the time from review to investigation, (ii) expanding it to include additional review Websites and (iii) linking to an electronic survey.