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Contact tracing app – a tool for ending the COVID pandemic

Contact tracing app – a tool for ending the COVID pandemic

By Dr Ingrid Johnston, Senior Policy Officer, Public Health Association of Australia.

Editors note: When this article was published on the 28 April the COVIDSafe contact tracing app had been downloaded 2 million times. The number of downloads is expected to continue.

Imagine you have just been told you have COVID-19. We know this is infectious, so the chances are, you may well have given it to others already. You’ve been asked – who have you been in contact with over the past 14 days? With the current distancing guidelines in place, answering that question is easier than it would usually be. But 14 days is a long time. You starting thinking – I went to the supermarket a few days ago. I was in the check-out queue a long time. Who did you come into contact with while in the queue? Impossible to say, isn’t it? What if it wasn’t? What if current technology could answer that question? If, at the press of a button, you could produce a list of people you had been in proximity to, who should now be quarantined and tested in case you gave them the virus, wouldn’t you want to press that button?

That is what the COVIDSafe app is all about. Yes, there are important practical and privacy issues which must be addressed. PHAA understands the privacy concerns that the public may have and will always advocate on the public’s behalf for appropriate protections to be included, as part of its support. Government has developed the app to ensure that no unnecessary data are being collected; and introduced legislation to ensure that the data cannot be used by anyone else and for any other purpose. The app must actually work properly, and there is provision for deactivation at the end of all this. And we need to find a way to include those who do not have or are unable to use smartphones. Developing this is not a simple proposition, and more time for consultation would have been ideal. But time is of the essence here – every day counts – and  the fundamental purpose and reason for developing and using it is sound. Not just sound, necessary.

To end the COVID crisis, we have to identify, and isolate  those who have the virus and track a high proportion of their contacts to ensure they are quarantined. The challenge is knowing who those contacts are.  As the clusters of cases related to overseas travel and super spreader events subsides, identifying cases becomes more important and more difficult.

If it’s possible to engage technology to help us with that task, we’d need a really good reason not to do it. The better we are at identifying cases, the more quickly we can isolate them, reducing the spread of the virus and ending the crisis sooner. Having efficient and highly effective contact tracing methods will help support a transition to normal distancing, easing the burden on people and families that have lost jobs, and the significant mental health challenges that accompany the current restrictions.

The app works using Bluetooth to record when the phone comes close to another phone with the app on it. That encrypted data is stored on the handset, and stays there either until it is automatically deleted after 21 days, or until it is uploaded by the phone owner to a central server, where it is decrypted. GPS is not used to track location, and the data collected are not available to anyone unless the handset owner authorises it. The decrypted list of names, mobile phone numbers, postcodes and age ranges, will only be available to local health authorities, and used to advise those who have been in proximity to someone since diagnosed with COVID-19. This is very similar to the contact tracing that is done currently by state health departments and public health units, but they will in addition have access to these digital contacts (their mobile phone number). News reports indicate that it has been tested by the Cyber Security Cooperative Research Centre, who are supportive and comfortable with the security and privacy settings in place. Most importantly, the app is voluntary to use. It’s a long way from the kind of surveillance state China relied upon to control the virus.

But the app will only be effective if enough of us are prepared to use it – the more people use it, the safer we all are. Studies from Oxford University in the UK show that if 60% of the population use the app, it will limit the number of cases in the population to below the threshold where hospitals and ICUs become overwhelmed.  This is far higher than the 20% uptake seen in the Singapore version, and relies on other elements of the package of responses including speed of testing.

Public health principles outlined in the Ottawa Charter for Health Promotion in 1986 say that –

“people cannot achieve their fullest health potential unless they are able to take control of those things which determine their health… Health is created by caring for oneself and others, by being able to take decisions and have control over one’s life circumstances, and by ensuring that the society one lives in creates conditions that allow the attainment of health by all its members”.  

This would not ordinarily involve using an app in this way. But, these are not ordinary times. The contact tracing app is not only a tool for health authorities. It is a tool for us, the people, to take control of things which are currently determining our health, and to enable us to care for others, and beat the virus as a community.


Photo by Adrienn from Pexels

One response to “Contact tracing app – a tool for ending the COVID pandemic”

  1. Steve Watson

    Would you really be standing in the supermarket queue for more than 15 minutes next to the same person? Standing next to someone at 1,5m for 15 minutes or longer would certainly be remembered if you are practicing social distancing (particularly in Victoria where restrictions have not eased at all). If someone sneezes or coughs in your path but you have not spent 15 minutes with them, does that mean you cannot catch the virus? Should the time spend with someone be less than 15 minutes to be of any use? The privacy issues are a distraction but I hope the 15 minutes and the app is based on some solid science.

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