In mainland China, a health code that dictates where citizens can travel has been mandatory since the pandemic hit. Meanwhile, Hong Kong’s contact tracing app doesn’t even know the user’s name.

That gap in surveillance has become a major sticking point in protracted talks about restarting quarantine-free cross-border travel, which could happen in a limited capacity as soon as December, the South China Morning Post reported late Thursday.

Earlier this month, Hong Kong Chief Executive Carrie Lam told a local news outlet that she had no plans to add a tracking function to the city’s LeaveHomeSafe app. But she also warned that residents would need to download their records if they wanted easier access to the mainland.

“The main concern is that many Hong Kong people are quite concerned about the privacy issues,” Lam Ching-choi, a member of the government’s advisory Executive Council, said in an interview. “This technical issue needs to be handled before they can really do it.”

Finding a solution is crucial if Hong Kong is going to open the mainland border, which Carrie Lam has prioritized over international travel.

While the territory has mostly matched China’s COVID-zero controls, imposing some of the world’s harshest quarantine measures, city leaders have struggled to find a tracking system that both convinces Beijing to the unlock the border and avoids triggering a public backlash.

Residents are already sensitive to mainland China’s growing control over the former British colony, after the central government imposed a sweeping national security law in June 2020 that has stifled free speech. Distrust of Beijing sparked mass street protests in 2019 and has contributed to a vaccination rate of about 60%, far behind the 88% mark in rival Singapore.

A security guard points to a QR code that displays a user's health code status at a shopping mall in Beijing in 2020. | BLOOMBERG
A security guard points to a QR code that displays a user’s health code status at a shopping mall in Beijing in 2020. | BLOOMBERG

“To what extent the Hong Kong government could adopt an authoritarian approach on this key public health issue would serve as an indicator on how far authorities would go to convert Hong Kong to another Chinese city,” said Xiaomeng Lu, director of Eurasia Group’s geotechnology practice.

Hong Kong officials are now considering imposing a health code system similar to fellow special region Macau, with only those rated green able to enter the mainland, Sing Tao newspaper reported this month.

In October the South China Morning Post reported that the government had submitted three proposals to Chinese officials about how a Hong Kong health code could work, including transferring LeaveHomeSafe records to a mainland app on a voluntary basis for those who wished to cross the border.

“The government is trying not to develop another system with active tracking data because it won’t be accepted by the general public,” Lam Ching-choi said. The passive tracking system was “generally accepted,” he added. The LeaveHomeSafe app has been downloaded nearly 7 million times in the city of 7.4 million people.

“The mainland really wants to track individuals over 21 days before crossing the border as well as after crossing the border,” he said. “When you go into mainland, you need to be actively tracked.”

Without a trace

Unveiled in November 2020, Hong Kong’s LeaveHomeSafe app employs a passive tracking model that allows users to access public venues by scanning a QR code image that pegs the location to their phone number.

Data is stored on the user’s smartphone for 31 days but isn’t uploaded to a third-party server, according to a government website explaining how the app works.

Still, the app is only mandatory at restaurants and bars that stay open as late as 2 a.m., with residents allowed to write down their name on paper at other venues.

If a COVID-19 case is later confirmed at a venue, the app notifies users who were there at a similar time — but, crucially, not the authorities. Government contact tracing relies on establishments handing over the written records, which are unverified, to find the others.

In mainland China, it’s a very different story. Every smartphone owner must download an app with a health code — a QR certificate that classifies people as green, yellow, or red and dictates where they can go.

A green certificate grants access to public venues and transport, a yellow one suggests heightened risk of exposure to COVID-19 infections and could trigger quarantine, while a red one means the holder is infected and needs to be isolated.

A customer fills in their personal details for COVID-19 contact-tracing purposes before entering a restaurant in Hong Kong. | BLOOMBERG
A customer fills in their personal details for COVID-19 contact-tracing purposes before entering a restaurant in Hong Kong. | BLOOMBERG

Multiple companies offer health code apps — a result of private firms and local authorities rushing out their own versions at the beginning of the pandemic. That health code is generated from a number of data points, including a user’s legal name, national identity number, close contacts and recent travel details.

Chinese citizens must also have a separate “itinerary card,” formally known as the “Communication Big Data Itinerary Card,” jointly developed by government bodies and state-owned companies like China Telecom Corp. Ltd. and China Mobile Ltd.

Using satellite navigation signals, the itinerary card tracks a user’s precise movements regardless of whether they check into a venue.

Residents’ pushback

Hong Kong is now ramping up use of its own app. This month it became mandatory for entry to government buildings, with plans afoot to roll those requirements out to all restaurants, according to local media.

Residents are pushing back. Electronics shops have seen an increase in demand for burner phones, while five people were arrested earlier this month on suspicion of using a fake app to enter a government building.

In September, Hong Kong police arrested three pro-democracy students, citing their calls to boycott the government’s contact tracing app as evidence of state subversion under the security law — a potential sign of the consequences facing those who resists the push.

“I’m not sure if I should trust the app or not,” said Chan, a 40-year-old who works in the pharmaceutical profession and asked only to be identified by their last name.

“The government has shown itself to move the goal posts whenever they want. I don’t trust them with my data and I don’t know how they will use it.”

In a time of both misinformation and too much information, quality journalism is more crucial than ever.
By subscribing, you can help us get the story right.