A smartphone app has been launched statewide and can alert users if they come into close contact with someone who has been exposed to COVID-19.

Gov. Jay Inslee, along with the state Department of Health (DOH), announced the launch of WA Notify on Monday. The app is an anonymous exposure notification tool meant to help slow the spread of the novel coronavirus.

By adding WA Notify to their smartphones, state residents can be alerted if they spent time near another WA Notify user who later records that they have tested positive for COVID-19, a state press release said.

WA Notify uses privacy-preserving technology jointly developed by Google and Apple and works without collecting or revealing any location or personal data, the press release said.

WA Notify is free and can be enabled in iPhone settings or downloaded as an app from the Google Play Store for Android phones. Users can opt out at any time.

Several states, including Virginia, New York and Colorado, and countries such as Ireland and Canada are using the technology, the press release said.

“Secure, private and anonymous exposure notification technology is an important tool for Washington,” Inslee said. “We’ve deployed WA Notify in 29 languages so as many Washington residents as possible can protect themselves, their loved ones and their communities.

“I encourage everyone to start using WA Notify today so we can continue to work together to contain this virus.”

Data models for three counties in Washington found that COVID-19 infections and deaths could be reduced if even a small percentage of people enabled WA Notify. Studies from Oxford University and Stanford also show that the more people who use exposure notification technology, the more effective it can be, the press release said.

When voluntarily activated, phones with WA Notify use Bluetooth technology to exchange random codes with the phones of other users they are near. It does so without revealing a user’s identity or location.

Users who test positive for COVID-19 can enter a verification code provided by a public health official into WA Notify so other users who have been near them within the past 14 days can be anonymously alerted and take appropriate action.

During a press conference Monday, Inslee said there were already more than 200,000 state residents registered for WA Notify.

Clallam County Health Officer Dr. Allison Unthank supports the additional tool for tracking potential exposures.

“I think that is a great additional tool in our tool box,” she said. “I certainly recommend everyone activate that app on their phone if they have a phone that can do that.

“This is all anonymous and it is all voluntary, so no one can track your information unless you say so, and if — for instance — you test positive, people in your circle would be notified, but it wouldn’t be with your name, they’d just be notified they were exposed,” she continued.

“It’s a safe thing. It’s a good thing. I activated it on my phone, because I think it’s really important for me to know if I’ve been exposed, so I don’t expose the entire (Emergency Operations Center) if I go to work.”

Jefferson County Health Officer Dr. Tom Locke noted that while the county has been able to keep up with the demand for contact tracing so far, other counties in the state have not been able to, so this app is another way to track possible exposures.

“We hope that it will be effective, especially when there’s high volumes of cases,” he said. “It’s becoming very hard for most health departments in the state reaching all contacts. They’ve had to depend on cases notifying their contacts.”

Clallam County confirmed 11 new cases of COVID-19 Monday, while Jefferson County confirmed five, Unthank and Locke said.

Both counties continue to be in the state’s high-risk category, with case rates of 218 per 100,000 population for the past two weeks in Clallam County and about 138 per 100,000 in Jefferson County, Unthank and Locke said.

Clallam County has confirmed 499 cases since March, with 152 active cases, three patients currently hospitalized and two deaths, according to Clallam County Public Health data.

Jefferson County has confirmed 167 cases since March, with 14 active cases and one death, according to Jefferson County Public Health data.

Using WA Notify

To turn on WA Notify on an iPhone:

• Go to Settings

• Scroll down to Exposure Notifications

• Click “Turn On Exposure Notifications”

• Select United States

• Select Washington

If you haven’t received a notification on your iPhone, you may need to check your device’s notification settings and make sure you’re on the latest iPhone firmware. You may also need to check to see whether Government Alerts are enabled on your device.

DOH also lists installation instructions for the Android app, which users must download to opt into the service. The department asks you to search for the “Washington Exposure Notifications app” — but you should instead search for “WA Notify”:

• Go to the Google Play Store

• Download the WA Notify app.