Researchers are increasingly looking at these devices and other such wearables as a possible early warning system for the deadly virus. Last month, scientists at the West Virginia University Rockefeller Neuroscience Institute said they had created a digital platform that can detect COVID-19 symptoms up to three days before they show up using the Oura ring, a wearable fitness and activity tracker.

An app developed by the researchers uses artificial intelligence to forecast the onset of COVID-19 related symptoms such as fever, coughing, breathing difficulties and fatigue, with over 90 percent accuracy, according to the university, the Agence France Presse (AFP) reported on June 7, 2020.

The researchers said the system could offer clues of infection in people not yet showing symptoms -- helping address one of the problems in detection and containment of the deadly outbreak.

Separately, Scripps Research Institute has enrolled more than 30,000 people -- and aims for much more -- in a similar study aiming to use wearables to find "presymptomatic" and asymptomatic people with COVID-19. Scripps researchers had already previously demonstrated the value of wearables in predicting influenza in a study published in January 2020 in the British journal The Lancet. Early indications suggest the devices "have the potential to identify people who are presymptomatic but still infectious," said Jennifer Radin, a Scripps epidemiologist leading the research.