Covid app

The app, called CO Exposure Notifications, provides a new tool to fight the spread of COVID-19 while using anonymizing technology to protect privacy. (Photo by Bria Light/Telluride Daily Planet)

We all know how distracting that little bleep or buzz can be, especially the sound of a notification alert popping up on your cellphone. Like an itch on your nostril, it’s nearly impossible to ignore, even when it’s merely an unnecessary interruption alerting you to new shows on Netflix or click-baiting headlines. Now, the Colorado Department of Public Health and Environment (CDPHE) is encouraging cellphone users to add an app with a  chirp that actually helps protect one’s health and the health of those nearby.

The app, called CO Exposure Notifications, marshals the ubiquitous cell phone buzz in the fight against COVID-19 as the virus continues to spike across the state and country. The app uses anonymizing Bluetooth technology — not GPS location — to determine proximity to other phones opting into the app. If an app user then voluntarily reports positive test results, it will notify other phones that have come within six feet of that person’s phone for over 15 minutes over the previous two weeks.

“Firstly, apps using this system cannot track your location,” says a CDPHE video explaining how the technology works and protects privacy. “Second, this system does not share your identity with Google, Apple or other users.”

To anonymize identity, the app generates a random sequence of numbers, or “tokens,” that change frequently. When the phone detects another phone nearby for over 15 minutes that has also downloaded and opted into the app, the phones exchange these anonymous tokens via Bluetooth. If an app user then tests positive for COVID-19, they can voluntarily report their results to the app, which then notifies the phones within the previous two weeks with which it exchanged an anonymous token. The identity of those who report positive results is never stored or revealed, with notification recipients simply made aware that they may have been exposed to the virus.

Health officials are encouraging more people to use the app, which relies on crowdsourced data — that is, opting in and self-reporting of positive results — to increase its effectiveness in stopping the spread of COVID-19.

“Awareness and identification are key to stopping the spread of COVID-19,” said Grace Franklin, San Miguel County public health director. “Exposure Notifications complement the current testing and case investigation process by alerting individuals of possible exposure to the virus. This is especially helpful for people who are asymptomatic, meaning they don’t have any symptoms but can still spread the virus. When many people have enabled Exposure Notifications on their phones, people who are asymptomatic will know they should get tested, learn they are positive for COVID-19 and quarantine until they are no longer infectious.”

Since the app went live last month, over a million Coloradans have opted into the app, with Governor Jared Polis pushing for another million Coloradans to download and use the app. 

“This is a powerful new tool that is already going to start having an impact,” Polis said during a Nov. 13 press conference. “Over 17 percent of the population has opted in. The research models out of Oxford show that at about a 15 percent adoption, which we’ve now exceeded, we can expect about an 8 percent reduction in infections and a 6 percent reduction in deaths.”

Along with following the advice of public health officials to take appropriate precautions, the app offers an additional measure with which to fight the pandemic and flatten the curve. 

“Exposure Notifications, like wearing masks and keeping our distance from others, is another way to keep ourselves and everyone in our communities safe from the spread of COVID-19,” said Franklin. “We can use this to better understand potential exposures and quickly determine next steps to contain the spread of the virus — such as staying home, getting a test, or postponing trips or events.”