COVIDWISE is the first statewide deployment of the COVID-19 exposure notifications system application programming interface jointly created by Apple and Google.
Virginia is offering residents a COVID-19 exposure notification app that does not rely on personal information or location data but instead uses Bluetooth signals to alert other app users that they’ve been in contact with an infected person.
COVIDWISE was built by the Virginia Department of Health (VDH) in partnership with development from Spring ML using CARES Act funding. It marks the first statewide deployment of the COVID-19 exposure notifications system application programming interface jointly created by Apple and Google.
The app works by using Bluetooth beacons to exchange anonymous tokens – or random strings of numbers -- that change every 10 to 20 minutes. iOS and Android devices that have the app installed will passively and anonymously share these tokens if they are within close proximity for at least 15 minutes. When a phone receives a beacon from a nearby device, it will record and securely store that beacon locally.
Meanwhile, individuals who test positive for COVID-19 are notified by VDH and given a six-digit PIN that expires in 48 hours they can use to share their test result with the app. In addition to adding another layer of privacy protection, use of the time-sensitive PIN also prevents malicious actors from uploading fake test results.
Each day, each user’s local COVIDWISE app downloads a list of all keys associated with positive COVID-19 results in Virginia and checks them against the keys from phones it has encountered in the last 14 days. Besides identifying matching keys, the app also estimates the infection risk the using the date, time and the duration of the contact as well as the strength of the Bluetooth signal, which approximates the distance between app users. If a predetermined risk threshold is met, users will be notified through the app that they may have been exposed to someone who has tested positive for COVID-19 and given instructions from the Health Department on next steps.
Use of the app is completely voluntary, and anyone who downloads it can choose whether or not to receive exposure notifications, officials said. Those who test positive for COVID-19 are not required to share their results anonymously through COVIDWISE. Users have the ability to delete the app or turn off exposure notifications at any time.
Virginia officials stressed the app’s privacy protections. “Random keys are changing frequently to protect your identity” VDH CIO Suresh Soundararajan said in a virtual press briefing on the app. “No personally identified information is collected, and all the data that's collected … is the Bluetooth signal strength -- and even those are basically encrypted.”
The app will continue to exchange anonymous keys with other COVIDWISE users who have notifications enabled even when they travel outside Virginia, but because positive test results can only be uploaded with the PIN supplied by VDH, the app will much less effective outside of the commonwealth.
According to VDH Director of Health Informatics Jeff Stover, the Association of Public Health Laboratories plans to host a national key server for any state that is using the Apple and Google technology. States with a state-specific program could switch to that national server, so that tokens indicating positive test result notifications could be shared with other states.
VDH is still working on integrating the privacy-protecting COVIDWISE exposure notification app with its existing suite of contact tracing programs that manage lab results and active cases as well as the human investigators who are on the phone talking with patients, Soundararajan said. Meanwhile, VDH is strongly recommending those who test positive to download COVIDWISE and use their PIN to upload their token.
Widespread use is critical to the success of this effort, and VDH is launching a robust, statewide public information campaign to make sure Virginians are aware of the COVIDWISE app, its privacy protection features and how it can help reduce the spread of the virus, officials said.
“Knowing your exposure history allows you to self-quarantine effectively, seek timely medical attention, and reduce potential exposure risk,” State Health Commissioner Dr. M. Norman Oliver said. The more Virginians use COVIDWISE, the greater the likelihood that you will receive timely exposure notifications that lead to effective disease prevention.”
Everyone with an Android or Apple phone is strongly encouraged to download and use COVIDWISE, officials said. By working together and using every tool at our disposal, we can protect ourselves and our communities.