Food inspectors reveal plans to use restaurant review websites like Yelp to help them identify unknown outbreaks of food-borne illnesses, according to a CDC report.

More than 48 million people in the U.S. get sick from contaminated food each year. Harmful bacteria are the most common cause of food-borne illnesses. While some outbreaks come to the notice of health experts, others remain unknown. To better identify such illnesses, health inspectors are now roping in restaurant review websites like Yelp in their investigations.

According to a CDC report, restaurant goers often take to such site to report bad service, undercooked food and even diarrhea and vomiting after dining at a certain joint. Making maximum use of these reviews, researchers from the New York City Department of Health and Mental Hygiene looked to see whether they could use outbreaks of food-borne illness as a sign that restaurants aren't up to sanitation codes.

For the study, researchers considered 294,000 restaurant reviews posted on Yelp between 20012 and 2013. Among these, 893 contained words like "vomit," "diarrhea" or "food poisoning." More than 50 percent of the reviews containing such words fitted the conditions of a potential food-borne illness.

Investigating these reviews further through calls and texts, researchers found that there had been three food-borne illness outbreaks affecting 16 people that were not reported to the health department. Researchers also found violations in food handling at three establishments that included workers not washing their hands before handling food, not storing food in the refrigerator and the presence of mice and roaches.

As promising as this new tool seems, it may not be ideal, according to study authors. One reason is because many reviewsers can't be reached on phone or through emails to get a better understanding of the symptoms they may have faced after dining at a particular restaurant. Secondly, going to reviews and flagging them is not only time consuming, it is also labor intensive.

"We know we don't identify all of the outbreaks that are out there, and this is just another tool to do that," Dr. Sharon Balter, medical epidemiologist for the New York City Department of Health and Mental Hygiene said, according to media reports. "We have a lot of reviewers and a lot of restaurants in New York, which made this a good place to try it out."

There have been many other attempts to spot outbreaks of food-borne illnesses. Last year, Utah launched an "I Got Sick" website to make reporting suspected food poisoning faster and easier. The Chicago Department of Public Health helped develop a system that contacts people who post complaints on Twitter.