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App-prehension: COVID-19 contact tracing comes to your cellphone.

20 Oct 2020 4:05 PM | Anonymous

Social distancing restrictions have eased and we’re once again enjoying meals at restaurants. It’s an old favourite leisure activity, with a twist: before sitting down, we scribble down our names and phone numbers.

If COVID-19 was present while we ate, a public health officer will call, warning us of possible exposure and requesting we take appropriate precautions. It’s called contact tracing and it’s fundamental to controlling the pandemic. But what else might our personal information be used for?

Many of us are only now learning about contact tracing in the wake of the COVID-19 pandemic. It’s not a new concept and is regularly used to reduce the spread of other communicable diseases such as measles and hepatitis through having people self-isolate to break the chain of transmission.

Though valuable, manual contact tracing has its drawbacks. Reaching contacts by phone is slow, and a person might unknowingly spread the disease to others by the time they are contacted. If you’re trying to reach one or two people, this isn’t a problem. Increase that tenfold, and things get complicated.

Plus, human memory is hardly foolproof. People may simply not remember who they were in contact with or simply cannot provide contact information of strangers in line at the bank or those with whom they shared a subway car. People may also deliberately give false names and numbers to preserve their anonymity.

The problem: public good versus personal privacy? The solution, say experts, may lie in palms of our 21st century hands: the cellphone.

The basic idea is quite simple: we download an app and as we go about our day, cellphones in hand, they communicate to other app-equipped cellphones in range. When someone tests positive for COVID-19, a notification is sent to everyone whose cellphones came into close proximity with the newly infected person. Abiding by pandemic protocol, those who have been notified self-isolate and are tested, indicating if positive themselves, and the process repeats.

With this swifter and broader system of cascading notifications, tracing cellphones stands out as the perfect fix.

While that might just be true in respect to reducing the spread of infection, it only holds until a key concept is introduced into the framework: individual privacy. It’s a concept that giving up personal information, though benefitting the health of society, may put at risk.

This is no small stumbling block. Effective contact tracing using cellphones must carefully balance both the individual’s right to privacy and the interest of public health.

Canada’s Privacy Act protects personal information, including what can be collected and how it is to be used. With contract tracing, any information that is unnecessary, such as exact user locations, should not be collected. Otherwise, in the wrong hands, apps built without privacy in mind could quickly degenerate into a surveillance tool.

Most countries have adopted some level of anonymization to keep user identities private, but another obstacle to privacy lies in where collected data is stored. Within what’s called a centralized architecture, data is uploaded to a server that is controlled by the government health authority. Within a decentralized architecture, data is stored only on user phones.

Centralized systems, like those used by China and South Korea, are more extensive in the data they collect, including a user’s GPS location history. These apps amount to true contact tracing systems, favouring public health response over privacy.

The most commonly pursued solution has been a decentralized system where GPS location is not recorded or stored. Instead, cellphone proximity learned by Bluetooth determines who needs to be notified of potential exposure. Known instead as exposure notification systems they, in contrast to true contact tracing apps, put more emphasis to privacy.

Canada’s exposure notification app, COVID Alert, is rooted in user choice. Whether to partake in exposure notification and whether to share COVID-19 status with the app are entirely up to the user.

A voluntary app, however, comes with its own self-imposed restriction to public health. To be effective, greater than 60 per cent of the population has to fully participate. These rates have proven to be decidedly difficult to reach, as evidenced by Singapore’s TraceTogether app clocking in at only 37 per cent participation at the time of writing. Australia’s COVIDsafe sits at 22 per cent.

Some governments have heeded past warnings, speaking to their belief that voluntary systems are not enough.

In 2015, South Korea experienced an outbreak of the coronavirus-caused Middle East Respiratory Syndrome, or MERS, ultimately leading to the highest number of deaths of any country outside of the Middle East.

Cautiously looking to an inevitable future of epidemics, South Korea modified its law so that the government could collect personal data and security footage only during epidemics. Today, the movements of people who test positive for COVID-19 are traced and made public so that others can avoid paths of infection. Anyone can see where someone who has tested positive has been, down to the hour.

With little consideration for privacy protection, western democracies quickly squirm at the seeming injustice.

While we may be concerned about privacy in principle, we regularly give up private information for a small reward, a privacy paradox. We instinctively tell Google Maps where we are so it can help get us to our destination but take issue with being notified of exposure to a disease, where the stakes are much higher. 

Early on epidemiologists knew eradicating COVID-19 would not be possible, but that its containment very well could be. Contact tracing allows for chains of disease transmission to be severed. The caveat is there is a price to pay, and whether that price be privacy or public health is a decision for every individual government.

The choice, when given, to participate? Well, that one’s all ours.


By: Natalie Workewych

Natalie is a PhD Student studying Pharmacology at the University of Toronto. Her academic background includes an undergraduate degree in Biochemistry and Pharmacology. She hopes to encourage ideas through writing, and bring thoughts on science to anyone the least bit curious.


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