Utah was first in the nation last April to roll out a smartphone app to do COVID-19 contact tracing. Nearly six months later, the Healthy Together app is used by 94,000 of its residents - about five percent of the state's population.
As UCSF conducts a pilot test of a contact tracing app among its students, faculty and staff at several locations, challenges lie ahead.
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A survey of 5,000 adults by Parks Associates indicates roughly half, 52 percent, are willing to share tracking data in an app while 28 percent are unwilling. Twenty percent are willing but only with privacy protection, which falls far short of what experts say is needed.
"To get the level of benefit that would be needed to really bring the pandemic fully under control, you would need high levels of participation. 60, 70, 80 percent," said Prof. Michelle Mello, a health law scholar on the faculty of both Stanford Law and Stanford Medicine.
The same survey showed that nine out of 10 young people, ages 18 to 24, are willing to use a contact tracing app, but the number drops to 63 percent among seniors.
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The demographic difference could impact a goal of such apps.
"At 75 percent adoption of digital contact tracing, we get the benefits we need between 56 and 81% reduction in infections, about the same level reduction in deaths," noted Prof. Mello.
Still, a high participation rate among young people could be useful in providing symptom assessment tools, which is being done at Brigham Young University.
"You can do daily symptom checking," said Dr. Jennifer Kent, senior director of Parks Associates. "If you think you have symptoms, you can know right there, where do I go to get tested? And does my insurance cover it? And you can get your results back much more quickly."
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Healthy Together doesn't allow users to see if their insurance covers testing, but there is information about CARES Act funding for test results.
While there are potential hurdles, Stanford's Prof. Mello believes mobile app contact tracing is worth pursuing.
"There's going to be another virus, and wouldn't it be great to have a system like this stood up in time for it to be actually helpful in preventing the kinds of losses we've seen this time around," she said.
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