April 5, 2020

Health authorities are breaking out the Yellow Pages to fight COVID-19. Last Friday, Massachusetts Gov. Charlie Baker detailed a “powerful tool” to stop the coronavirus’s spread: contact tracing.

How it works: When a patient tests positive, you make a list of everyone they came in close contact with. Then, you find those people and make sure they self-isolate before infecting others.

That sounds straightforward, but contact tracing a new patient typically takes three days, according to Stat, which is “an insurmountable hurdle in the U.S., with its low numbers of public health workers and tens of thousands of new cases every day.”

It's worked elsewhere

South Korea used high-tech contact tracing to tame its outbreak. The government compiled GPS data, credit card swipes, and other info into a public log showing where COVID-19 patients had traveled.

Some countries (including the U.S.) are trying other methods, including looking at smartphone location data and developing Bluetooth systems that provide warnings if you’ve crossed paths with an infected person.

The hangup: Despite its widespread use in places like Singapore, contact tracing has raised concerns about privacy and governments following citizens’ whereabouts. Still, it's a term you'll be hearing a lot more of in the coming weeks.