Starting Tuesday, iPhone and Android users can opt-in to “DC CAN”—the District’s new coronavirus contact tracing technology. The tool will send push notifications to users if they’ve been in contact with a Covid-positive individual. iPhone users can opt-in to the tech through their phone settings; Android users will download an app.
While the city is currently able to notify named contacts of Covid-positive individuals, the new tool will help the health department to notify unnamed contacts or strangers who have had contact with a positive case. For example, if you were in close range of someone at a protest or on public transit and that person later tested positive for Covid-19, you would be notified that you might have been exposed.
DC officials say the tech will be anonymous and will not share location data: It uses Bluetooth to detect nearby DC CAN users. Similar to Virginia’s tracing app, the tool will generate anonymous keys unique to each user. If two people who have have opted in are near each other for a period of time long enough to risk exposure, the phones automatically exchange these keys through Bluetooth. The keys will be stored securely in each device; if an individual tests positive for Covid-19 and enters their positive status into DC CAN, then anyone with that individual’s key in their device during the previous 14 days will be notified they’ve been exposed to a positive contact.
DC CAN will be interoperable with any other states using the same platform. (Virginia is not; Maryland currently does not have any kind of contact tracing technology.) Even though use of the District’s technology is on an opt-in basis, it has the potential to greatly increase the city’s contact tracing abilities.
To opt in on iPhone, go to Settings, scroll down, and find the tab that says “Exposure Notifications” to turn DC Can on or off. On Android, search for the DC CAN app in the Google app store.