Maryland rolled out a COVID-19 contact tracing app on Tuesday, asking residents to opt-in to for an automatic alert if they may have been exposed to someone with the virus.
As the pandemic worsens in Maryland, the state aims to use the voluntary MD COVID Alert app as a supplement to conventional contact tracing.
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“I encourage Marylanders to use MD COVID Alert to help protect the people around them, including those they might not know directly,” Maryland Department of Health Secretary Robert R. Neall said in a statement.
Android and iPhone users in Maryland can expect notifications starting Tuesday requesting that they opt in, the state says.
Android users must download a free app and iPhone users can agree to join in their settings. Here's more on how to join.
Users who enable the app can expect to get a notification if they had close contact with someone who eventually is diagnosed with coronavirus. The notification will list the approximate date of exposure, but no personal information, officials say.
If you were exposed, you should get tested, begin a self-quarantine and monitor yourself for symptoms. Here's more on what to do if you've been alerted.
MD COVID Alert works using Bluetooth technology. The app will record what other phones users have been near recently, but won’t track your location, officials say.
Privacy is preserved in part using a system that assigns each user a new random number every 10 to 20 minutes. Every day, users’ phones will download a list of the random IDs previously encountered.
If one of those random IDs is associated with a coronavirus patient, the phone will send an alert listing the date of exposure.
“Privacy is important. MD COVID Alert does not collect, transmit, or store personal information of users, and the system is completely anonymous,” MDH Contact Tracing Unit Director Dr. Katherine Feldman said in a statement.
The MD Covid Alert is compatible with D.C.’s contact tracing app, plus the apps for New York, New Jersey, Delaware, Pennsylvania, North Carolina, Nevada, North Dakota, Colorado and Wyoming.
However, MD COVID Alert is not interoperable with Virginia’s COVIDWISE app. Maryland advises choosing the app that works for the region where you spend most of your time.