Cellphone users in Maryland can now use an app that will notify them if they have been exposed to someone who tested positive for COVID-19, the illness caused by the coronavirus.
Several states are beginning to use the technology in addition to traditional contact tracing methods, where staffers call people identified as physical contacts with those infected.
The idea is to capture people anonymously through their iPhones or Android devices. The technology uses a number that regularly changes and not people’s names or other identifying information, according to the Maryland Department of Health, which announced the system Tuesday.
The system, called MD COVID Alert, uses Bluetooth Low Energy technology. It does not collect or share information on a person’s identity or whereabouts. It uses the random IDs assigned a person once they’ve been nearby someone who tests positive.
Users who receive an exposure notification alert are advised to get tested, monitor their health for symptoms and quarantine. They also would get a date of possible exposure. Some users may receive a call from a contact tracer if their information is shared by an individual with COVID-19.
“MD COVID Alert complements our traditional contact tracing efforts to notify users of possible exposure to help contain the virus,” Maryland Health Secretary Robert R. Neall 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.”
The system does not automatically notify people of an exposure. People have to opt into the service by enabling notifications in their phone’s settings and selecting Maryland as their region. Android users need to install the MD COVID Alert app from the Google Play store.
The service is free and can be disabled at any time.
The state hopes the use of the app will supplement its efforts at contact tracing, considered a key tool to control spread of the virus, now on another steep upswing in the state.
An April study by Oxford University researchers found that if half of the people in an area used such an app, it would have a profound impact on cases because people likely would be notified earlier, before they showed symptoms.
The study also found that using anonymous IDs would protect privacy, an issue of concerns about contact tracing in general.
“Privacy is important. MD COVID Alert does not collect, transmit, or store personal information of users, and the system is completely anonymous,” said Dr. Katherine Feldman, the state health department’s contact tracing unit director. “We’re asking Marylanders to add their smartphones to the fight against COVID-19 by using MD COVID Alert.”
For more information about MD COVID Alert, go to covidlink.maryland.gov/mdcovidalert.