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How an Alberta contact-tracing app would work to help in fight against COVID-19

How a contact tracing app would work to help in fight against COVID-19
WATCH ABOVE: Albertans will soon be able to use an app that could help track if they have been in contact with a person who has COVID-19. Nicole Stillger explains.

Albertans will soon be able to use an app that could help track if they have been in contact with a person who has COVID-19.

The province said it’s in the final testing phase of a new contact-tracing app.

“This is simply taking our decades-old public health approach into the 21st century,” chief medical officer of health Dr. Deena Hinshaw said Thursday.

The app is voluntary and the provincial government said information collected is stored within people’s phones and not with them.

“The benefit of this app is in speeding up information-gathering to support the contact-tracing work that our public health workers are already doing,” Hinshaw explained.

The app would use Bluetooth technology to track when you come in the vicinity of other phones also running the app.

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The idea is — if a person using it tests positive for COVID-19 — health authorities could in turn notify any phones that had been near that person, and potentially figure out where the infection occurred.

READ MORE: How does COVID-19 contact tracing work? Alberta doctor explains

One expert said a key issue with the Bluetooth signal is it acts as an “identifier.”

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“Your phone always sends out the same identifier — and so somebody could use this to track you,” Urs Hengartner, an associate professor of computer science at the University of Waterloo, said on Friday.

“That’s why it’s very important not to broadcast the same Bluetooth identifier continuously. Instead, it should be a random value — a value that changes over time.”

He said these apps are never going to be perfect.

“There’s going to be so-called false positives and false negatives,” he explained.

“Imagine you’re living in an apartment building — and so your neighbour ends up with COVID-19 and Bluetooth goes through walls. Now your phone tells you you better be careful like you may have COVID-19 too.

“There’s also a wall between you and your neighbour, so you could not have gotten infected — this would be a false positive, so people get erroneously alerted and anxious.”

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Hengartner also noted there has to be a high number of people also using the app for it to be effective.

“I’ve seen some numbers saying that at least 60 per cent of the population need to have this app,” he explained. “Popular apps tend to be on 10 per cent of people’s smartphones.

“Singapore has deployed to some degree, and they had only like 11 per cent of the people using this app — and they ended up with a second wave.”

READ MORE: Alberta to launch contact tracing app to help in fight against COVID-19

Information and Privacy Commissioner Jill Clayton said she had not yet received detailed information about the app, despite being provided with a “high-level overview about the goals of the program earlier this month.”

“It will be important for the Government of Alberta to provide Albertans with a clear, easy to understand description of privacy practices,” Clayton said in a statement.

“Knowing in plain language what types of personal information may be collected, how that information will be used and in what circumstances it will be disclosed will assist people in choosing to opt-in to using the app.”

The province said the app will be available in the coming weeks once the trials are finished.

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