‘Yet another tool’: Experts say efficacy of smartphone COVID-19 tracing app will depend on public participation

MADISON, Wis. – While the vaccine may be months away for many in the country, there’s another tool on its way that can go in the hands of everyone in Wisconsin as soon as next week.

The State announced the WI Exposure Notification, a voluntary and free smartphone app that uses Bluetooth to alert users if they’ve been in close contact with another user who has tested positive for COVID-19. Whenever someone tests positive for COVID-19, they’ll be sent a code that can be entered into the app, which is used to anonymously send an alert to users with whom they’ve shared a Bluetooth signal.

Gov. Tony Evers said the app, the result of a collaboration between Google and Apple already used in other states, does not use or collect device location.

“The app is free and it’s anonymous so that your privacy is protected even as you help us in stopping the spread,” Evers said.

“There are games on your phone that collect a lot more personal data than this will be doing,” said Ajay Sethi, an associate professor of population health sciences at the University of Wisconsin-Madison who works on modeling COVID-19 spread. “It makes it convenient for people to notify others that they’ve tested positive. People might download it because they would want to know if they came across somebody who has tested positive.”

CONTACT TRACING APP: Because the voluntary app uses Bluetooth technology, it will not collect user location data and will remain completely anonymous.

Posted by News 3 Now / Channel 3000 on Thursday, December 17, 2020

It’s similar to the Safer Badgers app that UW-Madison students, faculty and staff will use during the spring semester.

“I’ll say it’s not a panacea of any kind, but it is yet another tool,” he said.

“This app makes contact tracing a more effective, efficient tool,” said UW-Madison Professor Oguz Alagoz, who also models COVID-19 spread. He said while the app has its own barriers, it can cut down the on lag and unknowns that come with manual contact tracing, such as if a COVID-positive person can’t name everyone they’ve been in contact with or if a contact tracer doesn’t have the information to get ahold of someone.

Alagoz said because the app doesn’t track personal data, it’s hard to say exactly how effective it has been elsewhere, but he noted that people ages about 15 to 45 have been more likely to download the app.

“We know that those are the groups that, at least in Wisconsin recently, that’s the group where they have too many contacts and they are less careful,” he said. “If younger people are the ones who download (the app) and pay more attention, that’s a big win for us.”

“I think the key thing is whether or not people will adopt it,” Sethi said. “We’re talking the 50% range.”

He said he’ll be watching to see if enough people download the app for it to be effective.

“I’m a little bit hesitant to say we’ll get a lot of buy-in, but at the same time, there’s a lot of reason to buy in,” Sethi said. “Sometimes adoption is not overnight. When it comes to apps, they go viral just like the virus. We’ll see how it goes.”

The app will be available in the Google Play store for Android users and iPhone users can turn on the app in their phone’s privacy settings. It launches Dec. 23.