In less than a year, a Chicago Department of Public Health website launched to track Twitter traffic for foodborne illness complaints turned up 21 restaurants that failed unannounced health inspections (Harris JK et al. MMWR Morb Mortal Wkly Rep. 2014;63[32]:681-685).

Dubbed Foodborne Chicago, the website uses an algorithm that parses Chicago-area tweets that include the words “food poisoning.” Project staff members then review the tweets for references to stomach cramps, diarrhea, vomiting, or other terms than may indicate food-borne illness. Staff members respond and ask the Twitter users to report on Foodborne Chicago their illness and where they ate. The web forms go directly to the Chicago 311 system that handles nonemergency city services. From March 2013 to January 2014, Foodborne Chicago identified 2241 “food poisoning” tweets, of which 270 described specific food-borne illness complaints. Eight of those 270 tweets mentioned a visit to a physician or a hospital emergency department. Overall, 193 food poisoning complaints were submitted through Foodborne Chicago. About 10% sought medical care.

The complaints triggered unannounced health inspections at 133 restaurants; 21 failed their inspections and were closed. Another 33 restaurants passed with conditions, indicating that serious or critical violations were identified and corrected.

In related news, Carol Beach of The Packer says Foodborne Chicago researcher, Jenine Harris of Washington University in St. Louis, reported health officials in Boston and New York City are considering similar Twitter taps.

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 an additional tool to help public health authorities detect outbreaks earlier.