Internet searches for gastrointestinal symptoms preceded the rise in coronavirus cases weeks later, indicating where pandemic hot spots would form, a study by Massachusetts General Hospital found.

The study, published in the journal Clinical Gastroenterology and Hepatology, utilized an approach used more than a decade ago to monitor pandemic influenza trends, which researchers realized could be utilized to track COVID-19.

Researchers found that patients regularly complained of similar GI symptoms, including ageusia, abdominal pain, loss of appetite, anorexia, diarrhea, and vomiting. Using Alphabet Inc.’s Google Trends tools and Harvard Dataverse COVID-19 database, researchers studied search trends during the period between Jan. 20 to April 20.


During that time, results indicated that search trends most strongly correlated with cases in New York, New Jersey, California, Massachusetts and Illinois, which all presented high case numbers three to four weeks later. The timeframe of four weeks yielded the "strongst correlation between symptom search volume and COVID-19 case volume."

A Google search page is seen through a magnifying glass in this photo illustration taken in Brussels May 30, 2014. Google has taken the first steps to meet a European ruling that citizens can have objectionable links removed from Internet search results, a ruling that pleased privacy campaigners but raised fears that the right can be abused to hide negative information.   REUTERS/Francois Lenoir (BELGIUM - Tags: SCIENCE TECHNOLOGY POLITICS) - RTR3RK8U

File photo - A Google search page is seen through a magnifying glass in this photo illustration taken in Brussels May 30, 2014 . (REUTERS/Francois Lenoir)

“Our data underscore the importance of GI symptoms as a potential harbinger of COVID-19 infection and suggests that Google Trends may be a valuable tool for prediction of pandemics with GI manifestations,” Kyle Staller, director of Mass General’s gastrointestinal motility laboratory, wrote in the study.

The main concern that researchers noted is the lack of more specific factors in search results, such as "demographics, occupational factors, or Internet use patterns."

"While our study provides information about popular search terms and their relationship to incidence, it is important to note that the relative nature of Google Trends data does not allow for defining specific increased interest thresholds."


Scientists are also testing for traces of the coronavirus in wastewater to identify places where COVID-19 is spreading, according to Bloomgerg.