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COVID-19 in Maryland Health Care

Department of Health Offers COVID-19 Exposure Tracking App

Maryland’s Department of Health launched its MD COVID Alert system Tuesday in an effort to bolster the state’s contact tracing effort and combat the virus as the infection rate climbs.

“MD COVID Alert complements our traditional contact tracing efforts to notify users of possible exposure to help contain the virus,” Robert R. Neall, Maryland’s Health secretary, said in a statement. “I encourage Marylanders to use MD COVID Alert to help protect the people around them, including those they might not know directly.”

This COVID-19 exposure alert system is a phone application that uses Bluetooth Low Energy technology to track its users and notify them that they may have been exposed to a person who has tested positive for the coronavirus. 

Beginning Tuesday, iPhone and Android users will receive push notifications inviting them to download the software. The program can be enabled by setting iPhone users’ region to Maryland in their Exposure Notifications in their phone’s settings menu; Android users can install the app through the Google Play Store.

Once downloaded, the program will assign participants a random ID, or a computer-generated string of numbers. Random IDs are to change every 10-20 minutes so as not to identify users or track their location.

The participant’s phone will regularly track and download the random IDs that have been associated with positive COVID-19 test results and compare them to the IDs of other users whom the participant’s phone has recorded close contact with within 48-hours of a positive test or the onset of symptoms. 


Users can turn on the MD COVID Alert system in their iPhone settings. Android users can download the app through the Google Play Store. Screenshot by Danielle Gaines

iPhone users can identify their exposure date by opening the Exposure Notifications menu in their phone settings. For Android users, the date will appear in the app’s exposure alert. 

According to the COVID Link website, exposure dates are displayed as an approximated 24-hour period to preserve participant anonymity.

Users can alert the program that they have tested positive by entering a verification code sent to them by a contact tracer during the Department of Health’s case investigation. 

If there is a confirmed match, the program will alert users of the date of their potential exposure based on the date, amount of time and proximity of the user to the confirmed case. No other information, including exposure location, is shared.

If users receive an exposure notification, they are urged to track their symptoms, get tested and quarantine themselves. Users may receive a call from a contact tracer if they are identified by a person who contracted the virus.

App users are anonymous, data is not collected from their smartphone and their location isn’t tracked. The system, administered by the Office of Enterprise Technology, uses Bluetooth rather than GPS tracking to allow the app to send alerts to people without identifying where the contact was made or whom each phone belongs to. 

According to the program’s privacy policy, data is stored on the user’s smartphone for 14 days and is shared only if “and until the user has a positive COVID-19 diagnosis and elects to share this information within the system.”

The Maryland Department of Health stated that the MD COVID Alert system was designed to protect users’ personal information. Screenshot by Danielle Gaines

“Privacy is important. MD COVID Alert does not collect, transmit, or store personal information of users, and the system is completely anonymous,” Dr. Katherine Feldman, MDH Contact Tracing Unit Director, said in a statement. “We’re asking Marylanders to add their smartphones to the fight against COVID-19 by using MD COVID Alert.”

The program is compatible with similar systems deployed in Washington, D.C., Delaware, Pennsylvania, New York, New Jersey, North Carolina, Nevada, North Dakota, Colorado and Wyoming. Users who travel to these areas will continue to receive exposure notifications if they come into close contact with an infected individual.

According to the COVID Link website, officials are hoping the app will soon be interoperable with Virginia’s infection alert system, and recommend that users who frequent Maryland, D.C. and Virginia use the system that is compatible with the region where they spend the most time.

Participation is free, voluntary and can be disabled at any time. Those who choose to participate can opt-out by removing the app from their Android device, disabling the feature on their Apple device, turning off their Bluetooth capability or powering down their phone.

The app is not available for iPads, tablets, or smartwatches.

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Department of Health Offers COVID-19 Exposure Tracking App