DENVER (KDVR) — More than three years after the initial COVID-19 shutdowns in the U.S., the nation’s pandemic response continues to wind down.

Colorado announced Wednesday that it’s ending its exposure notification system. The program sends cell phone alerts to users who were recently around another user who tested positive.

The federal public health emergency on COVID-19 is set to end on May 11. Because of this, Apple and Google are decommissioning the service, according to the Colorado Department of Public Health and Environment.

CDPHE said its exposure notification system will also end on May 11.

“A message will appear on users’ phones alerting them that the system is no longer operational and prompting them to delete their data,” CDPHE said.

Months into the pandemic in 2020, Colorado launched its exposure notification system. Users were able to opt into or out of the free system on their Apple or Google devices.

It uses Bluetooth to trade anonymous tokens between nearby devices that are enrolled in the system. If a user tests positive for COVID-19 and enters the result into the service, an anonymous notification is sent to other users who, over the last 10 days, were near them long enough for COVID-19 exposure.

CDPHE said the end of this system does not immediately mean a total end to notifications.

“CDPHE will continue to send text messages to anyone with a reported positive COVID-19 test result that include a link to disease control information through July 2023, if their phone number is on file,” according to the release.