Exposure notification apps could be more effective if they’re better at assessing risk
0Reported today on The Verge
For the full article visit: https://www.theverge.com/22555764/exposure-notification-app-google-apple-covid-improvement
Reported today in The Verge.
Exposure notification apps could be more effective if they're better at assessing risk
Joanna Masel is quick to recognize that the contact tracing apps built to track cases of COVID-19 aren't as good as they could be. The apps, built on a framework offered by Apple and Google, aren't used by many people in the United States and didn't seem to make a big difference in the spread of the virus.
But Masel, an evolutionary biologist at the University of Arizona and advisor to the team behind the Arizona exposure notification app, thinks there are ways to make the apps more useful. In a paper published last week with colleagues, she outlined one possible improvement: adjust the apps so that they could better recognize situations where people who are exposed to the virus have a lower risk of catching COVID-19. Then, they may not need to quarantine for a full 14 days.
"The possibility of this technology is way better than the best implementation so far," she says.
Most of the apps used in the US alert someone to a potential COVID-19 exposure if they were in the same area as someone who was potentially infectious for greater than 15 minutes. It's a crude metric for figuring out how risky that interaction was, and recommendations from the app tend to be similarly broad: they instruct people to isolate.
It's possible to add more nuance to that process. Masel's paper outlined a method for including information on where someone was in relation to a sick person, which could be a proxy for how much virus they may have been exposed to. Someone closer or directly in front of a person with COVID-19 would inhale more virus than someone a few steps back and to the side. Combined with other information (like how long the sick person had shown symptoms before