One year and four months after the Covid-19 outbreak in Wuhan, China, the pandemic situation is still severe in many countries, mainly Global South countries, while it is under control in other nations. Among the countries that have controlled the outbreak situation in some ways, they used various methods such as vaccination, forced quarantine, closing borders, centralizing medical resources, etc. One of the most controversial methods is contact tracing, initiated either by governments or big technology corporations. People’s Republic China, the authoritarian regime known to execute mass surveillance among its citizens, created and adopted a contact tracing system shortly after the Covid-19 outbreak in January 2020. This essay intends to take a closer look at this system and the method and techniques used in it. While it successfully stops the Covid-19 virus transmission and helps return people’s life in Mainland China back to normal, experts share the concerns that the government might abuse the information gathered for contact tracing. However, what is often ignored is the general public’s penetration of Covid-19 patients’ privacy because of this contact tracing system.
Indeed, contact tracing is not a fairly new idea. Experts around the world already adopted such methods long before the digital age. In the 1918 influenza epidemic, one of the most acute global pandemics in the last century, the New York City Department of Health conducted contact tracing in the patients’ neighborhoods, workplaces, and vessels after they were put in quarantine through surveys and looking through registration papers (Aimone 2010). This method might be successful when the patients are less mobile, and the relative population size the patient had contact with is relatively small. In the Ebola outbreak in the Republic of Congo, local health officials and international organizations such as the World Health Organization also conducted contact tracing on patients as well as dead bodies. They mainly trace the patients’ family members and healthcare workers who have treated the patient. This method largely depends on patients’ reports on their close contacts and local residents and the healthcare workers’ self-awareness (who.int). However, it is rather difficult if the patients are deceased because the local health officials would not be able to identify the large gatherings in which the patients have participated and thus is not sufficient for contact tracings in large areas.
However, the methods that were used in the past are not fully applicable to Covid-19 because of their unique characteristics. People in this era, unlike in the 1910s, are highly mobile, and places like the European Union where there is no border control or entry record make it harder to do international contact tracing. Unlike Ebola, Covid-19 is not infrequently asymptomatic. And technically speaking, Covid-19 needs no physical contact to infect people, and the patient needs not to be in a closed space to infect others. It could be the case that one who carries the Covid-19 virus and is talking with another person on the road, and a third person who walks by gets infected.
Additionally, one needs not be physically presented at the same time to get infected by Covid. The Shanghai Municipal Health Commission points out that one might get Covid-19 by touching the door handle which a Covid-19 virus carrier has touched. The National Institute of Health also pointed out in March 2020 that the Covid-19 virus can survive on surfaces for days (nih.gov). The 8th edition of the National Diagnosis and Treatment Plans for Covid-19 indicates that the Covid-19 virus is capable of aerosol transmission (nhc.gov.cn). There were even cases that the packages of frozen food have gotten tested positive for it (dw.com). All these characteristics show that the past contact tracing methods are not completely applicable for this highly transmissive disease and that a new model is needed, which means new ethical questions.
The People’s Republic of China, where the first Covid-19 outbreak occurred in January 2020, has become one of the most successful countries in controlling the global pandemic and managing to keep its mainland Covid-free. Currently, life in Mainland China has basically come back to normal compared with the pre-Covid era. All domestic travelings have resumed since July 14, 2020, after being suspended for around 140 days (souhu.com). And at that time, the vaccine of Covid-19 had not been widely available for the general population. All schools, including K-12 and universities, have been open for in-person classes without social distancing policies since September 2020, when the new school year began. It is, therefore, worthy analyzing that how does a country with more than 1.4 billion population, most of them living in highly congregated buildings and large communities with high dependence on public transportation, was able to manage the crisis and get back to normal successfully, compared with other countries with similar or better healthcare resources such as the United States or the United Kingdom.
Admittedly, as an authoritarian regime, the Chinese government has many rights that other democratic countries do not have to make them easier and more efficient to control the pandemic. For example, the ability to build up temporary hospitals in days and to mobilize some of the healthcare workers to the hotspot of the pandemic. Additionally, the central government also has the right, which the United States federal government does not have, to temporarily lock down an entire city, as it did to Wuhan in January 2020. Moreover, the government forced every possible close contact to get one or multiple nucleic acid tests. However, none of these policies are possible without identifying the hotspot and possible close contacts. And that is where the Covid-19 contact tracing technology played an essential role.
Every citizen in Mainland China must be equipped with an attaching app called “Health Code” from February 2020 (zjol.com.cn). Later, it is also mandatory to have a “Journey Card.” The Health Code is a QR code in green, yellow, or red. One must scan their QR code in order to use public services, enter buildings, or travel to another city. The Journey Card is used to confirm one’s routine or travel history in the past fourteen days. To clarify, the major difference between these two codes is that the Health Code is used as a qualification and record for public and private services, while the Journey Code is mainly for the government to gather geolocation data.
Initiated by regional governments, the Health Code was created in order to prove one’s health condition. Since it is created regionally, different provinces used to have separate databases, and it is not a universal pass in the country when it was first used in February 2020. In other words, if one travels from one city to another, it is likely that one needs a new Health Code at that time, depending on the city one lives in. In fact, even though there is a universal health Code in China, it is managed by the regional government, and many cities or provinces still have different policies regarding the details of the Health Code’s application.
Generally speaking, one needs to apply for the Health Code by entering personal information such as age, gender, date of birth, the place one lives, and the place one has recently been to. One must follow the Health Code regulation of the city of one’s current address. One also must submit a recent standard photo of oneself. Some provinces, such as Jiangsu, require their residents to fill out more specific information than other provinces, such as the unit number one lives in. And after one’s application, the local government will verify one’s information and the photo. Once the application is passed, one would have a QR code attached to one’s AliPay app in green, red, or yellow.
Regarding its color, green means one is clear for public transportation, entering public buildings and amusement parks, and traveling. Yellow code means that one would be restricted from many activities, depending on regional policies. However, unlike what the article “Covid-19 contact tracing apps: why they are so popular in China”, published on the website of the Mercator Institute for China Studies of the Freie Universität Berlin, the red codes are not only “assigned to users infected with the virus” (Kosta et al. 2021). A red code simply means, from an individual perspective, that this person is restricted from public and private services. Being infected with the Covid-19 virus is a sufficient but not necessary factor of a red code.
Indeed, the color of the Health Code not only relates to personal health status, it also depends on one’s place of residency because it also indicates whether one’s current place of residence is low, medium, or high risk of Covid-19 by using GPS technology. If the GPS locating service detects that one is currently staying at a place that is categorized as a high-risk region, even though one is not tested positive for the Covid-19 virus, nor is one a close contact of any patient, one will still receive a red Health Code. Depending on policies, the “region” can be a specific street or a whole city. For example, in Shanghai, it is possible that the residents in one block have red codes, while the residents of the next block have green codes. It is worth noting that the Health Code does not change if one’s GPS service is not on, and it does not frequently change with one’s routine in one city.
In addition to the domestic version of the Health Code for domestic citizens who stay in Mainland China during the pandemic or have not recently gone abroad, which is introduced above, there is also the international version for Chinese citizens who recently experienced international travels or went back from other countries and regions. Starting in March 2021, while most of the non-Chinese citizens are forbidden to enter the Chinese borders, Chinese citizens have also faced limitations due to contact tracing if they want to return to Mainland China. Since the government does not have geolocation data for people overseas, Chinese citizens are required to apply for the international version of the Health Code with their negative Covid-19 test results and negative IgM antibody result. Only after they get a green QR code will they be allowed to get abroad. At this time, their information has been recorded in the contact tracing system. And after the plane lands, people must be quarantined in certain hotels in the city they entered for at least 14 days after testing negative for Covid-19. At this time, their data will be transferred to the domestic system, and they will have green codes if they test negative again for Covid-19 at the end of the 14-day quarantine.
The Journey Card, on the other hand, provides more specific geolocation information by using phone towers. Developed by the Chinese Department of Communication and Technology and three major telecom operators, the Journey Card, unlike the Health Code, is a universal pass in Mainland China and is directly managed by the government. All of the user information is stored in the same database. After agreeing with the term of use, one needs to submit the places one has been to for the past 14 days. At the same time, the system would compare those with the mass data it has collected through phone towers. If the information is correct, one will receive a Journey Card. Unlike the Health Code, the Journey Code does not use as proof of personal health conditions and can not be used as the only verification to travel and to use public services. It is designed to check whether one has been to a high-risk region for the past 14 days for contact tracing purposes.
Since May 2020, China has had a relatively low daily Covid-19 cases, and most of them are people who have recently traveled back and are tested positive during quarantine (who.int). And these patients were quickly transferred to hospitals without contacting domestic populations. There were a few community transmission cluster cases in some cities such as Chengdu and Dalian in winter 2020, but the local government successfully stopped the transmission by quickly identifying every single close contact and giving them nucleic acid tests immediately. Nevertheless, the Health Code and the Journey Card, the user ends of the Covid-19 contact tracing system, is just the tip of the iceberg. What lay behind the app, and what makes contact tracing so successful in China are geolocation data access, mass surveillance systems with facial recognition technology, the real-name system, and mobile payment usage.
To begin with, the contract tracing system is highly dependent on the geolocation data generated by GPS service on smartphones and phone tower signals. The smartphone penetration in China was around 50% in 2018, and it is still in continuous growth (statista.com). Considering the total population of 1.4 billion, it is an astonishing number of people who carry smartphones and have their geolocation data saved in the database. Additionally, 17.8% of the population are 15 or under, and 12.6% of the overall population are 65 or older. These two age groups have less individual mobility compared with the age group 16-64. Adding up the numbers, only 19.6% of the Chinese population who are likely to move individually or participate in social activities do not use smartphones frequently. Moreover, considering the national geographic difference and political issues that some regions like Tibet and Xinjiang have a less stable internet connection and higher poverty rate, and thus large clusters of people without smartphones, the smartphone penetration rate of Chinese people who are likely to be mobile and thus have a high risk to transmit Covid-19 virus is very high.
Since the Health Code is attached to AliPay, an online payment app developed by Alibaba company, it can only be refreshed when it is connected to the internet. Currently, 5G and 4G speed signal and Wifi services have already covered most of Mainland China. In 2020, there are more than Based on the GPS service, and the Health Code service would automatically acquire one’s location when one connects to the internet. Therefore, as long as one does not manually turn off the locating service on one’s phone, the Health Code app would continuously record the location information and thus contribute to the contract tracing process.
However, the drawbacks of the GPS-based Health Code app are rather obvious. To begin with, the GPS location is not specific enough to determine the close contacts of a Covid-19 patient in multi-floor conjugated buildings. Due to the amount of the population, conjugated housing and office buildings are rather common in China. Although possible, it is too time-consuming and cost-ineffective to identify and test every single person who has been in the same building as the patient. For example, if patient A went to a multi-building mall, brought a bubble tea with AliPay, and left immediately before testing positive for Covid-19, the GPS location would only show that patient A has been to the mall. That is where the online payment tracing method comes into effect.
In Mainland China, 86% of the people use mobile payment such as AliPay, WeChat Pay, Apple Pay, etc. (cac.gov.cn) In 2019, 36.2% of the national GDP went through digital money transfers (xinhuanet.com). This indicates that Chinese people rely on mobile payment a lot, and the country is making progress toward mass surveillance and a cashless society. Unlike cash, which is sometimes untraceable, electronic payment contains not only the amount of money and both parties in the transaction, it also shows the exact time and places the payment was made. Back to patient A example, the contract tracing team would know, by using the information on AliPay, that patient A had close contact with the bubble tea shop workers. Moreover, they would also know who pays at the same bubble tea store around the same time with patient A and prioritize them as likely close contacts. Thus, the contact tracing team would be able to test and quarantine those people who are more likely to get infected by the patient. With mass data of mobile payment, the Chinese government has more precise information about timing and location and thus manages contact tracings more efficiently.
Nevertheless, GPS data and mobile payment records are insufficient for building a Covid-19 contact tracing system for everyone in the country because people can simply carry others’ phones if they do not have a green code themselves or if they intentionally want to mislead the healthcare and government workers. Facial recognition technology and surveillance cameras fill in this gap.
In China, almost everyone’s facial information is stored in the national database due to the massive amount of cameras and ID requirements. Every Chinese citizen is required to take a clear, standardized photo when they apply for their governmental ID cards, an essential card for daily life. Therefore, every Chinese citizen’s facial features are already in the database before the Covid-19 outbreak. Since 2003, China has been establishing cameras in public places for what is claimed to be public safety purposes. Later, with the development of facial recognition technology and algorithms, the Chinese government fasted its pace in constructing closed-circuit television cameras in order to make it possible to monitor individuals’ behaviors in public space. Statistics show that there were 2.6 million surveillance cameras in Mainland China, which means that there is one camera per 6 people (Keegan 2019). These cameras are clear enough to identify each person and precisely capture individuals’ facial features. With these having been prepared, the Chinese government launched the SkyNet project, the largest video surveillance system around the world, in 2018. With this system, only milliseconds are needed to identify a person by comparing 106 crucial points on one’s face with the ID photo database (tech.ifong.com).
In order to prevent the situation that someone would intentionally use other people’s green Health Code, the government required that one needs to pass facial recognition verification each time it is used. As mentioned above, one needs to submit a current standard photo when applying for the Health Code. This photo, along with one’s photo on the government-issued ID card, is served as the “control group.” And when one opens the Health Code, one needs to go through a process similar to unlocking one’s phone using Face ID. Therefore, it is nearly impossible for people to use others’ Health Code.
By using facial recognition technology, the Covid-19 contact tracing team is able to locate close contacts in public facilities with mass population flows such as train stations and subway stations. On January 5th, 2021, Mr. Chen received a message from the health department, saying that he was in close contact with the newly discovered Covid-19 patient in Xi’an, Shanxi, a city in northwest China. Mr. Chen did not know the patient, nor did he live anywhere near the patient. When the patient’s routine for the past 14 days was published, Mr. Chen noticed that he did not go to the same place with the patient either. Later, it turned out that the contact tracing team found out that Mr. Chen was on the same subway train with the patient. It is worth noticing that the daily subway passengers flow is more than 2.6 million in Xi’an (xianrail.com). The science behind this successful contact tracing case is that the SkyNet cameras in the subway station capture everyone’s face when they get in, transfer, and get out of the station. Thus, the contact tracing team would be able to recognize the people who stand near the patient when walking in the subway stations. Additionally, by calculating the time and place Mr. Chen got in and out of the subway station and comparing it with the patient’s routine, the contact tracing team reached the conclusion that Mr. Chen was on the same subway with the patient and had the risk of being infected by Covid-19.
Another astonishing case of contact tracing, using the technologies and methods described above, happened in Qingdao, Shandong, in October 2020. Mr. Shao was a taxi driver in Qingdao, and he tested positive two times for the Covid-19 virus on October 10th and 11th after his wife was tested positive. Because of his career, Mr. Shao got in contact with dozens of people each day, which made the contract tracing process harder. The contact tracing team started with quarantining and testing all the residents in their neighborhood and people identified by Mr. Shao as close contacts. Later, the team identified the passengers of Mr. Shao who used mobile payments by tracing the transaction records on Mr. Shao’s account. The team also started plate tracing by using the traffic cameras–many of them are able to capture photos that are clear enough to identify the divers and sometimes the passengers. The contact tracing team was able to figure out the places Mr. Shao stopped by calculating the time difference he appeared in the cameras. With the traffic cameras and other surveillance facilities on the street, the team successfully identified every passenger of him. On October 13rd, two days after Mr. Shao’s diagnosis, the government had traced 52 passengers and done 4.2 million nucleic acid tests (Zhao 2020). On October 16th, the contact tracing team figured out that Mr. Shao had 183 journeys and took 231 passengers in total from September 29th to October 10th, including 24 people living in other provinces. (Yang et al. 2020).
In residential areas with fewer cameras, fewer mobile payment sites, and more congregated buildings, phone tower locating technology fills in the surveillance and contact tracing gap. Although the smartphone penetration rate in China is relatively high, there still are people who do not own smartphones, do not use mobile payment methods, and do not frequently take public transportations. Many of them are seniors and underprivileged poor people; among them are farmers and factory workers. However, almost every person in China owns cell phones with SIM cards. And with phone towers that send and receive cell phone signals, the government would be able to locate the phones.
In 2010, China started the Real-Name System, which requires people’s government ID number when buying new SIM cards. Later, the government required every single phone number to be registered by its owner in 2016 (gov.cn). This system not only allows the government to verify people’s identities on the street or in public transportations such as the high-speed railroad, but it can also track phone users’ geolocation data if phone towers are available nearby. According to the statistics of the fourth season of 2020, China has already built more than 5.9 million phone towers and thus making it possible to trace people’s geolocation data in most of the places in mainland China (Gao et al., 2020).
The phone tower locating technology, along with the Journey Card, provides more broad geolocation data generated from those who do not own or use smartphones. Because it can provide one’s location information based on the phone tower signals. Even though one does not connect to the internet, one’s geolocation information would still be revealed. Especially in the situation when one neighborhood is marked as a high-risk region, and everyone who has been that is required to quarantine. If one walks by that neighborhood without connecting to the internet, and there are no cameras on the road one walks by, one might be able to avoid the quarantine process. However, as long as one carries a phone with a SIM card, one’s activity would be detected. In fact, there are cases in Shanghai that one’s Health Code changed from Green to yellow when one drove by an area with a medium risk of Covid-19, even though one has not contacted anyone in that region and did not connect to the internet.
Nevertheless, although the contact tracing system is rather successful, considering that China has been almost Covid-free for a year, there are serious privacy problems and violations regarding these technologies and systems. The general criticism for this contact tracing system mainly focuses on the possible information abuse by the government, which is kind of cliche because it is rather straightforward that the Chinese government built the surveillance system decades before the Covid-19 outbreak and was intended to, and indeed used for, political oppressions. But the privacy concerns that are newly arisen by the contact tracing system is that the public now has access to others’, mainly Covid-19 patients’, detailed personal information that is unrelated to Covid-19 contact tracing, which was held exclusively by the government. And this is devastating to people’s privacy and their personal safety.
After finishing the primary contact tracing, the government would announce the patient’s name, race, gender, age, profession, residence location, family relations, and sometimes medical conditions in their public press conferences and on their official social media accounts. They also reveal very detailed information about the patient’s life for the past 14 days. And they claimed that doing this could warn those who had been to the same place with the patient but were not found by the contact tracing team and encourage them to voluntarily conduct Covid-19 nucleic acid tests. The details are so specific that everyone who sees the post on social media would be aware of the name of the dumpling shop the patient stopped by and possibly the number and kind of dumpling one bought, which is not necessary for contact tracing.
This creates a potential privacy inequality because only the Covid-19 patients’ life routines are available to the public, while others remain unknown. By testing positive for the Covid-19 virus in Mainland China, one does not automatically nor willingly give up their privacy rights on everything. Also, giving up one’s privacy rights to the government does not equal handing it over to the general public. Although it might be necessary for someone, presumably people who live in the same neighborhood or town with the patient, to know about the places the patient has been to for the past 14 days, it is certainly unnecessary to make it public at news conferences, broadcast it on the news, post it on social media and publishes it on newspapers. It is unfair to the Covid-19 patients that someone who lives on the other side of the world knows the name of the club they go to.
Additionally, what would be revealed by 14 days of detailed information of one’s daily life is more than individual behaviors. When all these details are presented, people could easily speculate patterns of one’s life. People who live thousands of miles away who have zero possibility to be in close contact with one Covid-19 patient would know detailed patterns of the patient’s life. The public would be aware of at what time every day does the patient go to work, in which supermarket does the patient usually shop, and with whom does the patient spend time daily. Although this kind of information has been available to the government long before the Covid-19 outbreak through the SkyNet program, the public did not, and shall not, have access to them. For there might be the situation that a woman is found by the domestic abuser from whom she ran away because someone posted her detailed life trails on social media for contact tracing purposes.
In December 2020, a woman, who will be referred to as Anna in this essay for privacy purposes, was tested positive for Covid-19 virus after a voluntary test at a local hospital in Chengdu, Sichuan, a metropolitan in Southwestern China with a 16.63 million population (gov.cn). The local government locked down the city and started the contact tracing process immediately. Later, her trait for the past 14 days was published along with a map showing her routes. Anna is around her 20s and had a lavish social life. Like many people of her age, she went to nail salons, ate hotpot for dinner, and went to clubs. However, after the local government revealed her route, her more detailed personal information, such as government-issued ID number, apartment number, and family relationships, was posted on social media by a certain individual. Later, Anna was blamed and cursed by many people because of her social life. And there were comments under the post which revealed her personal identity that threatened to beat her because, according to the commenter, she should be responsible for the lockdown of the whole city and the spread of the virus.
With a closer look into the system, the Chinese contact tracing model is highly based on the previous-established surveillance system and new technologies. The user end of it, the Health Code, and the Journey Card, though it seems complicated in some ways, are only the small tip of the iceberg. What remains under the water is the mass data created by GPS locating services, phone towers, and mobile payment methods. Along with the facial recognition technology, the real ID system, and the massive amount of CCTV cameras established for the SkyNet program, the Chinese contact tracing system is able to identify the close contacts of each Covid-19 patient and stop the transmission effectively. Nonetheless, this method remains controversial because, regardless of the most-attacked part that the Chinese government is likely to abuse the data, the privacy of the Covid-19 patients is lost because their life trails and personal information are known to the general public which creates personal safety concerns.
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