Google today announced that the Exposure Notification API it had developed in collaboration with Apple has been updated with several improvements designed to make it more useful to public health authorities.
The update to the API includes the following changes:
- When an exposure is detected, public health authorities now have more flexibility in determining the level of risk associated with that exposure based on technical information from the API.
- Bluetooth calibration values for hundreds of devices have been updated to improve the detection of nearby devices.
- The API now supports interoperability between countries, following feedback from governments that have launched Exposure Notification apps.
- To help public health authorities build apps more efficiently, we’ve added reliability improvements for apps and developer debug tools.
- We’ve improved clarity, transparency, and control for users. For example, the Exposure Notifications settings on Android now include a simple on/off toggle at the top of the page. In addition, users will also see a periodic reminder if ENS is turned on.
Google says it has heard feedback that public health authorities and developers want more technical guidance about how ENS works. In response, they have published the following resources over the last few weeks:
- Reference verification server to help guide public health authorities in building a server that allows verification of test results when users report themselves as positive for COVID-19.
- Implementation code showing how the Exposure Notification API works underneath the hood.
- Telemetry design explaining what de-identified diagnostics data is collected to ensure that ENS is functioning properly and securely.
Additional technical resources will be publicly shared as ENS is improved.
As of today, public health authorities have used ENS to launch in 16 countries and regions across Africa, Asia, Europe, North America, and South America, with more apps currently under development.
In the United States, 20 states and territories—representing approximately 45 percent of the U.S. population—are exploring apps based on ENS. We expect to see the first set of these apps roll out over the coming weeks. The Association of Public Health Laboratories also announced recently that it will host a national key server to support all U.S. states, which will allow people with Exposure Notification apps to receive alerts even if they travel across state borders.
