Tech Tent: Can we learn about coronavirus-tracing from South Korea?

It is a country that saw an early surge in coronavirus infections - and then used a mass of surveillance data to track anyone who might have come into contact with the virus.

On this week's Tech Tent we ask whether South Korea has set an example for others to follow.

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Back in late February, South Korea was battling the worst coronavirus outbreak outside China, with thousands of cases involving members of a church in the city of Daegu.

But now, despite a recent flare-up linked to a nightclub, the virus seems to be under control. The death toll in this country of 52 million people stands at 260, while in the UK nearly 34,000 people have died out of a population of 67 million.

So what has been the government's main weapon against the virus? In a word, data - a mass of information about the movements of its citizens.

Justin Fendos, professor of cell biology at Dongseo University in the South Korean city of Busan, tells Tech Tent about the scale of the operation to track the infection.

"They have taken information methods that are normally used by law enforcement to catch tax evaders or to track criminals, and they've repurposed those for public health use."

He describes three types of information being used:

• Credit and debit card transactions - they can show where someone has shopped or eaten, and how they have travelled across a transport network

• Phone location logs obtained from mobile operators giving a rough idea of which neighbourhood someone is in as they connect to different phone masts

• Details captured by South Korea's extensive network of surveillance cameras

"You'll find cameras usually in most restaurants and coffee shops, but also on street corners and things like this to catch parking violations," he says.

This information is used to track people who have been infected but also to trace their movements in the days before they tested positive so people who may have been in close contact with them can be alerted.

"This is very powerful because you can use this information to inform people who have been around that patient recently, and let them know that, 'Hey, you know, you might have been put at risk. And so maybe you need to go get tested.'"

A lot of this information is also made available via text alerts to people's phones and on public websites. Look for instance at the movements of case 10932 as recorded here.

You can see this person moving between restaurants, cafes, shops and offices in the days from 7-11 May before receiving a test result and being transferred to hospital.

There has been little opposition to this level of surveillance, something Prof Fendos puts down to cultural factors.

"Koreans are very reluctant to do things that harm other people. They're very reluctant to be responsible for someone else getting sick at the same time. There's also a kind of understood hierarchy where regular people tend to believe what the government is asking them to do," he says.

Privacy

It seems unlikely that such methods would prove acceptable in Western countries such as the UK, where a vigorous debate is under way about whether a contact-tracing app that stores some data centrally poses too big a threat to privacy.

But data ethics specialist Stephanie Hare tells Tech Tent that the question should not be whether such methods are acceptable but whether they are necessary.

"South Korea is a really interesting case study and we want to learn from it," she says.

"But we also must ask ourselves whether there are any other examples where people have not had to do that. And the fact is, there are plenty so we can look at them as well. "

She cites a number of Scandinavian countries and the Indian state of Kerala as examples of places which have succeeded in suppressing the virus without invading the privacy of their citizens.

It is worth remembering that we are probably still at an early stage in the battle against Covid-19.

The next few months will see many countries employ brand new technology in the form of bluetooth contact-tracing apps as they cautiously emerge from lockdown..

But there is a chance that neither flavour of such apps - centralised or decentralised - will prove effective, and that could mean more governments look to the brute force tactic of mass surveillance.