California to Launch COVID-19 Exposure Notification System

Shoppers walk through San Francisco's Union Square on Dec. 4, 2020, just days before San Francisco and four other Bay Area counties preemptively implement the state's regional stay-at-home order.  (Beth LaBerge/KQED)

Gov. Gavin Newsom on Monday announced the statewide launch of a smartphone app that notifies users when they have been exposed to other users who have tested positive for COVID-19.

The CA Notify app, which will be available to download across the state on Apple and Google smartphones starting Thursday, is a voluntary, opt-in program. That means "the more people that participate, the more effective this program can be," Newsom said Monday at a press briefing.

Developed in partnership with Google and Apple — and piloted by researchers at UC San Diego and UCSF — the app uses Bluetooth technology to exchange random codes between phones without revealing either users' identity or location. Any user who tests positive for the virus will receive a text from the state Department of Public Health with a verification code to enter into the app. Other users who have been within 6 feet for 15 minutes or more of that person in the last 14 days will receive an anonymous notification of possible exposure.

This is "an additional tool in the toolkit in terms of your safety protocols," Newsom said. He underscored that that the app protects each user's security and privacy and does not track locations.

"It's 100% private, 100% secure, 100% voluntary. You opt in or you choose not to," Newsom said. "We value privacy. California has long been a leader in terms of advancing the cause, and we don't want to do anything to set that cause back. And that's why we've been, frankly, a little stubborn and kept our eyes wide open in terms of [adopting] this technology."

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The efficacy of the app, however, will be based entirely on the number of people who actually choose to use it. A recent Associated Press analysis found that most states have been slow to adopt the technology, which was introduced a full six months ago. California is only the 19th state to do so.

In Connecticut, which has the highest app usage rate so far, only about 1 in 5 residents have opted into the notifications. The analysis found that public health officials are struggling to convince people to sign up amid rampant COVID-19 misinformation, as well as privacy concerns, tech issues and political polarization.

The app's availability in California comes as COVID-19 infection rates continue to soar across the state. Some 33 million residents — about 84% of the population — are now under sweeping new regional stay-at-home orders that significantly restrict most business operations and activities. Those orders went into effect Monday in Southern California and the San Joaquin Valley, where the number of available intensive care unit hospital beds fell below 15%. The restrictions have also been preemptively implemented in four Bay Area counties — including San Francisco, Contra Costa, Santa Clara and Alameda counties — and will go into effect in Marin on Tuesday.

Statewide, nearly 25,000 people have tested positive for the virus every day over the last week, a rate "substantially greater than what we’ve seen in the past," Newsom said. The 14-day positivity rate of 8.4% is almost three times what it was a month ago, he added, resulting in a 72% increase in virus-related hospitalizations, with nearly 86% of intensive care unit beds now filled.


Newsom on Monday also said California is contracting with a staffing agency to send more than 1,000 additional health care workers — most from outside of California — to understaffed medical facilities across the state. Additionally, he said, a handful of emergency field hospitals have been set up in areas across the state with limited medical capacity, and can open within days. Among them is the Sleep Train Arena practice facility in Sacramento, which will begin accepting a small number of patients this week.

The governor also announced that the first 327,000 doses of Pfizer's coronavirus vaccine will be delivered to the state by mid-December and distributed to health care workers and the most vulnerable populations. California, he added, expects to receive more than 2 million additional doses of the vaccine — produced by multiple drugmakers — by the end of the month.

"I expect and I really believe this: You're going to start getting good news and numbers that continue to significantly increase over the weeks, not just months, in terms of the availability of vaccinations," he said.