Cellphone-Based Contact Tracing May Be Harder Than It Sounds

One tool that’s getting talked about a lot in managing pandemic infection rates is cellphone-based contact tracing. Tracing consumer movements and interactions could be incredibly resource-intensive if done by hand – calling for roughly 100,000 workers to mount an adequate campaign in the US – but going the cellphone-based route could drastically reduce the level of resources needed to get the job done.

Not surprisingly, the tech giants of the world are attacking this problem. For example, Apple and Google recently announced that they were partnering to develop tools allowing organizations to leverage cellphones’ Bluetooth capabilities for this purpose.

As promising as this sounds, however, it could be some time before we overcome the obstacles to creating a practical location-tracking system. I was alerted to some of these issues by Harold Feld, senior vice president of public interest advocacy firm Public Knowledge, who follows telecommunications issues closely. (Harold is a long-time acquaintance in real life and a Facebook friend whom I consider myself lucky to follow. I am quoting his comments with his permission.)

In a recent Facebook post, Harold noted that while our cellphones do offer location-related services, they may not offer enough precision to do the kind of tracing we need to help contain the virus. “We are constantly told that our phones track us everywhere,” he wrote. “…[but] what is good enough for marketing or government surveillance is not good enough to confirm with whom you actually came in contact.”

Harold pointed out that most current approaches to cellphone-based contract tracking involve using Bluetooth beacons, which use Bluetooth low energy proximity sensing to transmit a universally unique identifier that can be picked up by compatible apps or operating systems. The device receiving the identifier and a handful of additional bytes can use this information to determine where the transmitting device is located.

When it comes to low-impact activity such as triggering a social media check-in or push notification, the current technology works well. However, contact tracing calls for a level of precision which this configuration can’t deliver, he said. “Bluetooth can go through thin barriers or further than 6 feet, but drop the power low enough to prevent overreach and you will likely under-reach in other situations,” he points out.

OK, maybe Bluetooth beacons won’t solve this problem as of yet. What about other forms of data the phones can access? They don’t fit the bill either, he says. “GPS and cell tower data are even less precise [than Bluetooth],” he writes. “In particular, we still don’t have solidly reliable tech for ascertaining height (though this is improving). That means that it would appear like I am in contact with every person in a building.”

The bottom line, he says, is that “we have enough[tech] to raise serious concerns, but not enough to actually do what we want it to do.”

Of course, we’ve been here before. To put it mildly, this is far from the only time when a promising technology solution turns out to unready for prime time. During the pandemic crisis, though, we can’t afford to spend much time kicking tires and wondering whether we can fix things. It would probably be smart to reach a consensus on whether these technologies can be adapted to suit the purpose and move on quickly if we don’t see a prompt win on the horizon. At least at a minimum, let’s realize that this may be a tool that helps more traditional contact tracing efforts and not the cure all for contact tracing.

About the author

Anne Zieger

Anne Zieger

Anne Zieger is a healthcare journalist who has written about the industry for 30 years. Her work has appeared in all of the leading healthcare industry publications, and she's served as editor in chief of several healthcare B2B sites.