US can learn from China, Singapore about using phones to track Covid-19 coronavirus

When someone tests positive for the virus, public health investigators get in touch with them, learn about everyone they’ve been in contact within a certain time frame, and then manually track down and notify all those contacts.Digital contact tracing automates a part of this process by relying on people’s phones to map out their ongoing web of physical interactions. As Recode previously described, “It works a bit like exchanging contact information with everyone you meet, except everything is designed to be anonymous and automatic.”This type of contact-tracing technology is already helping contain the spread of Covid-19 in countries like Singapore and Taiwan — but it has limitations. In March, the country released TraceTogether, an app that uses Bluetooth technology to help public health officials do contact tracing. One of the key government officials helping release this app explained these limitations of the technology and made the case for governments to continue investing in human beings to do manual contact tracing in addition to any tools they’re rolling out.“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, the product lead for TraceTogether, Singapore’s nationwide Bluetooth contact-tracing system, wrote in a blog post on Friday.Singapore’s experience suggests that even if there’s widespread adoption of Apple and Google’s contact-tracing tools when they are released, there are limits to their effectiveness.In the US, mandatory app-based contact tracing isn’t on the table for now. Apple and Google are also leaving it up to public health authorities to develop and manage the apps that will use their contact tracing tool. A Singapore government official working on the country’s contact-tracing app said it would need to see something like two-thirds of the population or more using it. Of course, that’s because those apps are all but necessary to get around and do basic day-to-day activities like go to work, enter the market, or ride public transit.In countries where the apps are opt-in rather than mandatory, we’re not seeing adoption rates nearly that high yet.This raises questions about how the US will be able to convince enough people to download the app, as compared to China’s more mandatory enforcement.Having an app tell you you’ve been exposed to Covid-19 is helpful, but it’s only the first step we’re seeing in effective international responses to controlling the pandemic. He said he’s hopeful about the US implementing new technologies around contact tracing but emphasized the need for public health agencies to provide adequate resources to follow up on this new data.Extensive contact tracing is less useful in a region that’s in the middle of an outbreak — like New York and California — where there’s widespread community transmission and people are already sheltering in place in their homes.But, in the future, when the number of cases in those states eventually declines and when businesses begin to reopen, contact tracing can help people safely reenter society.