Can COVID-19 exposure apps slow the spread of coronavirus?

Mike Bebernes
·Senior Editor
·7 min read

“The 360” shows you diverse perspectives on the day’s top stories and debates.

What’s happening

In the early stages of the coronavirus pandemic, there was a lot of talk about the role that Big Tech companies could play in helping track and control the spread of the virus. Those technological tools became a reality in the intervening months, but there is still a long way to go before they might make a significant dent in the scale of the outbreak in the United States.

On Thursday, California became the latest state to begin using an app developed by Apple and Google that uses phone data to notify people who have spent substantial time near someone who has tested positive for COVID-19. People receiving the alert are advised to self-isolate to break the chain of transmission. The apps use Bluetooth data that is anonymous and impossible to trace to individual users, experts say. Similar apps are now available to more than 150 million Americans in 18 states, plus Washington, D.C., and Guam.

The apps are intended to be an efficient supplement to human contact tracers, who track the spread of the virus by calling the contacts of people who’ve been infected. Contact tracing has been a key part of pandemic response for centuries, but tracing efforts in the U.S. have been hampered by limited resources, subpar testing availability and a reluctance among many people to participate.

Why there’s debate

Many experts see reason to believe apps could play a substantial role in limiting the spread of the virus if used by enough people. One model published by epidemiologists in April suggested apps could help end the pandemic entirely if 60 percent of the population utilized them.

The technology to do that now exists. At this point, however, reaching that level of usage appears to be more of a fantasy than an achievable goal. Lack of availability, limited awareness, technical hurdles and privacy concerns have meant only a small percentage of the population in participating states have taken advantage. The apps simply can’t work unless enough people use them.

Colorado’s app has been downloaded by 20 percent of the population, but in many other places, the rate is in the low single digits. Plus, downloading the app doesn’t mean the person will use it. App developers have found that a large share of users who have tested positive decline to send out exposure notifications, even though the recipients would have no way of knowing who exposed them. Comparable struggles have been experienced in other countries that have rolled out similar apps. The app from Google and Apple being used by states represents a low privacy risk, but there are hundreds of private apps that are much less secure, experts say,

The apps can still be valuable, even if the number of people who use them remains low. Every person who isolates after being notified of possible exposure breaks a chain of transmission that could potentially lead to thousands more cases. The apps could also be especially helpful in contained communities where participation may be higher than in the broader population. Health experts at the University of Arizona credit an early tracking app with helping stem an on-campus outbreak in the fall.

What’s next

Four more states — Arizona, Hawaii, Massachusetts and Oregon — have plans to launch their own versions of the apps in the future. California is seen by many as the true test case for the technology in the U.S. because of its huge and relatively tech-savvy population. Whether the Golden State will be more successful than other parts of the country in convincing people to use its app remains to be seen.



At the moment, the apps represent a missed opportunity

“In theory, such apps could bolster one of the most difficult tasks in pandemic control: Tracing the contacts of people infected with the coronavirus in order to test and isolate them if necessary. In practice, however, widespread COVID-19 misinformation, the complexity of the technology, overwhelmed health workers needed to quickly confirm a diagnosis, and a general lack of awareness have all presented obstacles.” — Bryan Anderson and Matt O'Brien, Associated Press

The apps can’t work if people won’t use them

“The system works only if a lot of people buy into it, but people will buy into it only if they know it works.” — Rae Ellen Bichell, Kaiser Health News

Political polarization means a significant share of the population will refuse to use them

“There’s a lot of things working against it. Unfortunately, in the U.S., COVID has been politicized far more than in any other country. I think that’s affecting people’s willingness to use tools to track it.” — Communications technology researcher Jessica Vitak to Associated Press

There's no national plan to increase user base for such apps

“This patchwork of different systems is one of the reasons that it's been so difficult to spur widespread adoption. The different apps have different installation instructions depending on where you live, and because they're not available to all Americans, they're often lost in the conversation about how the United States is responding to the coronavirus.” — Cat Zakrzewski, Washington Post

The apps’ emphasis on privacy makes the data they produce less useful

“These new apps prioritize privacy, but as a result they are not able to provide detailed information that might assist public health authorities or answer questions raised by people who receive exposure notifications.” — Lorrie Cranor, The HIll

Many Americans are still focused only on protecting themselves

“People load the app to know if they were around someone else who tested positive, but don’t want to notify others if they are positive.” — App developer Tim Brookins to the New York Times


The surge in infections may compel more people to use the apps

“They emerged as promising tools early in pandemic, but technical shortcomings, privacy concerns and dismissive attitudes in the United States toward safety measures undercut their benefits. The tide may be turning as cold weather and lockdown fatigue threaten a global surge in cases.” — Paresh Dave, Reuters

The current apps are the first test of what could be a powerful tool in future pandemics

“The lessons we will learn will impact how we respond to future pandemics. I think evaluating its impact right now, and determining whether this is going to be part of our plan for responding to future pandemics, is critical.” — Infectious disease expert Mike Reid to The Verge

The apps are built to protect privacy

“I’m usually the first person to caution that we shouldn’t trust corporations or the government with our sensitive personal data. But after investigating the data flowing out of these state-sponsored apps and services, I haven’t found much danger in having them on my phone.” — Geoffrey A. Fowler, Washington Post

Even a small impact will save lives

“Digital contact tracing is a potentially low-touch way for health departments to reduce the spread of COVID-19 by using smartphones to track who’s been exposed. And even if exposure notifications aren’t the panacea many technologists hoped for, new research suggests that breaking even a few links in the chain of transmission can save lives.” — Cat Ferguson, MIT Technology Review

The apps can help cover gaps in traditional contact tracing

“Health officials believe the alerts could be especially helpful in cases where an infected person has been in contact with strangers — for example in a bus, train or checkout line — who wouldn't otherwise know they were exposed.” Faith Karimi, CNN

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