Digital contact tracing is becoming available, but is it effective?

Technology companies are offering a new tool to countries and states trying to reopen their economies amid the coronavirus pandemic: digital contact tracing applications.

Touted as a way to track cases and isolate carriers quickly through the use of smartphones people already have in their pockets, the technological fix has gained significant attention from governments and private companies alike.

But it’s not clear how effective the alternative to traditional one-on-one interview-based contact tracing would be.

Apple and Google have been two of the leaders developing digital contact tracing and jointly released application programming interfaces this week for public health officials to build applications with.

The unprecedented collaboration from the Silicon Valley giants allows applications to use Bluetooth emissions to create a log of the people the phone’s user has come into proximity with. This would give officials a list of people that an individual infected by COVID-19, the disease caused by the coronavirus, may have passed it to.

There are a few potential roadblocks with the technology.

Experts warn Bluetooth’s limited range and accuracy may result in false positives.

The technology might show a contact between someone carrying the disease and a second person who is on the other side of a porous wall, Ashkan Soltani, a former adviser to the U.S. chief technology officer, wrote on the Brookings Institute’s TechStream with University of Washington professors Ryan Calo and Carl Bergstrom.

The product lead of TraceTogether, Singapore’s digital contact tracing app, said traditional contact tracing is superior.

“If you ask me whether any Bluetooth contact tracing system deployed or under development, anywhere in the world, is ready to replace manual contact tracing, I will say without qualification that the answer is, no,” Jason Bay wrote in a blog post.

It’s also unclear whether people would be comfortable with digital contact tracing. Public polling data suggests that Americans are hesitant to download apps from tech companies that would theoretically track who they interact with.

Only 50 percent of Americans who have smartphones capable of running such applications say they would download them, according to a Washington Post-University of Maryland survey conducted last month. 

“I don’t know that it’s a solution that is really going to work for an American citizenry that is already pretty preoccupied about privacy,” Mike Reid, an assistant professor of medicine at the University of California-San Francisco who is overseeing the city’s contact tracing efforts, told The Hill in an interview.

Apple and Google have explicitly built user data protections — like anonymized identity keys and a promise to end the system once coronavirus is contained — into the platform that have been praised by privacy hawks.

Even if privacy concerns are overcome, however, effectiveness will be hampered because only 81 percent of Americans have smartphones, according to the Pew Research Center.  

An Oxford University study found that 60 percent of a country would need to use an app for digital contact tracing to be an effective tool; Singapore has only managed 20 percent as of late April.

Experts also say that traditional contact tracing must be bolstered for digital contact tracing to be effective.

“Right now our focus needs to be scaling up tried and true person to person contact tracing systems that involve one human being contacting another,” Tom Frieden, former director of the Centers for Disease Control and Prevention, told The Hill in an interview.

According to Johns Hopkins University, the U.S. needs 100,000 more public health staffers to make contact tracing effective.

A group of leading health experts, including former Food and Drug Administration Commissioner Scott Gottlieb and former acting administrator of the Centers for Medicare and Medicaid Services Andy Slavitt, sent a letter to Congress last month calling for funding to train 180,000 more contact tracers.

Testing is another problem. Once individuals are notified of potential exposure, the next step in traditional contact tracing is getting a test.

“Long story short,” Reid, who has a background in tracing HIV cases, said, “you can’t do contact tracing unless you have enough testing capability to be able to test everybody that you identify.”

Experts also have raised concerns that a focus on digital contact tracing could complicate building up traditional capability.

“I definitely think it undermines our efforts,” Reid said when asked about the development of contact tracing apps.

Frieden said that while digital contact tracing could be an asset in the future, “right now, it is somewhat of a distraction.” 

Bruce Schneier, a fellow at the Berkman Klein Center for Internet & Society at Harvard University, told The Hill that issues with apps could negatively color users’ perceptions of contact tracing more broadly.

“My fear is that an app people lose trust in could cause more harm than good,” he said. “Some things in life an app can’t solve.”

The concerns with digital contact tracing don’t mean that technology companies don’t have a role to play in the coronavirus response.

Experts who spoke with The Hill all said companies could assist by helping build call center technology, public health record databases and movement records. They also suggested streaming services like Netflix could offer free subscriptions for those told to isolate, while Amazon could help provide them with food and other supplies.

Digital contact tracing is a case of tech companies rushing to a solution without considering its issues and potential implications, Frieden told The Hill.

“We’ve seen various companies ask the question, ‘can we build it?’ without asking the question ‘should we build it?’ and ‘will it work?’ ”