Contact Tracing Technology: Overview

Introduction

Contact tracing is an essential method of tracking and controlling the spread of infectious diseases by identifying and notifying those exposed to such diseases. It gained importance during the early twenty-first century as public-health officials worked to combat dangerous diseases such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola. The outbreak of the respiratory disease COVID-19, caused by a novel coronavirus, in late 2019 and its progression to pandemic status in 2020 further underscored the importance of contact tracing procedures, through which officials attempted to identify those who may have been exposed and encourage them to enter quarantine until their statuses could be determined.

Contact tracing efforts in the United States at the outset of the COVID-19 pandemic relied largely on traditional procedures such as notifying affected individuals by telephone. However, due to the immense scale of the outbreak, a number of health organizations, government bodies, and technology companies began to work to develop high-tech means of performing contact tracing functions. Developers focused on creating contact tracing applications for smartphones based on a variety of technologies, including the tracking of individual location data and Bluetooth-based sharing of personal identifiers. While proponents argued that contact tracing apps were not only a necessary innovation but also more efficient than traditional methods and safe for public use, critics asserted that such apps were of limited effectiveness, ignored the realities of marginalized populations, and posed security risks.

Understanding the Discussion

Bluetooth: Short-range wireless communications technology using short-wavelength ultrahigh-frequency radio waves.

Close contact: Under guidelines set by the US Centers for Disease Control and Prevention, any individual who has been within six feet of an infected person for fifteen minutes or more.

Contact tracing: The process of locating, notifying, and following up with individuals who have been in close contact with a person identified as having been infected with a disease.

Coronavirus disease 2019 (COVID-19): A respiratory disease caused by the virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Isolation: The practice of separating an individual who is confirmed to have been infected with a disease from those who have not been infected.

Quarantine: The practice of separating an individual who may have been exposed to a disease from others while waiting for test results to be determined or symptoms to develop.

History

The practice of contact tracing to track and prevent the spread of contagious diseases emerged as early as the late nineteenth century. Health officials in England, for example, sought to identify and quarantine those infected with diseases like smallpox. As the medical community gained understanding of the mechanisms of contagion, contact tracing procedures spread to numerous countries. By the early twentieth century the process began to be applied to a host of illnesses, including sexually transmitted infections like syphilis. During the emergence of the human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) epidemic in the 1980s, contract tracing efforts focused on identifying individuals with whom an infected person had had sexual contact or had shared needles became a vital component of the effort to combat those conditions.

The practice of contact tracing remained a key public-health practice in the first decades of the twenty-first century. During that period health officials sought to identify and notify individuals exposed to a variety of viruses, including those that cause severe acute respiratory syndrome (SARS), which emerged in 2002 and was contained by mid-2003; Middle East respiratory syndrome (MERS), first identified in 2012; and Ebola, a major outbreak of which began in late 2013. By 2017 the World Health Organization (WHO) had broken the process of contact tracing down into three distinct steps. In “contact identification,” an individual who has been confirmed to be infected provides the names of the people encountered and the locations visited since the illness began. In “contact listing,” officials reach out to each person who may have been exposed to the virus and provide information and guidance, potentially including instructions to quarantine. In “contact follow-up,” officials make regular contact with the identified individuals to monitor their conditions and test them, if needed. The medical community also articulated a clear distinction between the practice of isolation, in which individuals who have tested positive with infectious diseases separate themselves from others until they are no longer contagious, and that of quarantine, in which individuals who may have been exposed to viruses separate themselves from others while undergoing testing or waiting for symptoms to develop.

In late 2019 the medical community identified a novel virus belonging to the coronavirus family, which they identified as SARS-CoV-2. The virus spread primarily through respiratory droplets, such as those expelled when a person coughs, and caused a respiratory disease that would come to be named coronavirus disease 2019 (COVID-19). After being first identified in the city of Wuhan, China, in late 2019, the virus spread throughout the world during the first months of the following year, and in March 2020, the WHO declared the global COVID-19 outbreak to be a pandemic. As no vaccine for SARS-CoV-2 was immediately available, initial efforts to combat the COVID-19 pandemic focused largely on preventive measures, including frequent handwashing and use of hand sanitizer, the wearing of masks in public areas, and the closure of businesses, public institutions, and recreational areas known for large gatherings of people. Some countries, including China and New Zealand, also implemented strict lockdowns, while in other countries, such as the United States, the implementation and severity of stay-at-home orders varied based on location.

In addition to promoting preventive measures, health authorities throughout the world engaged extensively in contact tracing. They sought to identify individuals who had been infected—including those who showed no symptoms—and alert those potentially exposed to the virus as a means of limiting COVID-19’s spread. Much of the contact tracing that took place was carried out using traditional methods, such as contacting individuals by telephone, or through the use of established technology such as email and text messaging. A number of government entities and private-sector companies also expressed interest in developing more high-tech contact tracing tools, most notably including smartphone applications that could aid in the contact-reporting process or warn individuals that they may have been exposed to the virus.

Over the course of 2020, contact tracing apps emerged in Singapore, the United Kingdom, Canada, Iceland, India, and China, among other countries. Functionality varied among apps. Most served primarily to notify users if they had come into close contact with someone confirmed to have COVID-19, often through Bluetooth, while others made more extensive use of global positioning system (GPS) data to track users’ locations. Some technologies were designed to aid in monitoring and support of those in quarantine or isolation. South Korea notably used apps, along with other technologies like closed-circuit television footage, to track individuals’ locations to ensure compliance with quarantines. Similarly, China designated a risk level to citizens using app data and health information and then assigned travel restrictions based on a color-coded classification system.

Contact Tracing Technology Today

Contact tracing in the United States falls under the authority not of federal public-health bodies but of their counterparts at the state, county, or municipal level. As such, approaches to contact tracing and newly developed contact tracing technology varied from place to place over the course of 2020. In April of that year, rival technology companies Apple and Google announced that they had partnered with the goal of developing technologies to facilitate contact tracing. One such development was Apple and Google’s Exposure Notification System, in which a smartphone whose owner had opted into the system used Bluetooth technology to exchange identification credentials with other smartphones located nearby. Upon collecting those identifiers, the system checked the credentials against a list of identification numbers associated with individuals who had tested positive for COVID-19. The system then identified the smartphone’s owner if a match was found, thus providing an early notification that the individual might have been exposed to the virus. The technology could also alert the smartphone’s owner if a contact tested positive for COVID-19 in the days following their encounter. To implement the Exposure Notifications System, Apple planned to incorporate exposure notifications into its standard operating system for mobile devices, though on an opt-in basis. Google, on the other hand, enabled app developers working on behalf of individual states or localities to incorporate Exposure Notifications System technology into apps designed for phones running Google’s Android operating system.

Apple and Google’s technology proved popular among app designers worldwide, and by late September 2020, nine US states were using exposure notification apps based on the Exposure Notifications System. Another six states and Washington, DC, had such apps in development. Some states, including North Dakota and Utah, also experimented with other apps that made use of location data. Nevertheless, traditional contact tracing procedures remained the primary means of contact tracing in the United States into late 2020.

The development and introduction of contact tracing apps spurred debate over their effectiveness and potential ramifications. Proponents of such applications, including software companies and health-care providers, argue that contact tracing apps are not only more efficient than traditional methods, complementary to those approaches, and built for safety, but also serve a vital role in reopening society. Skeptics, particularly experts in data security and human rights activists, assert that such apps are of limited use for social and technological reasons, ignore the needs and habits of marginalized populations, and introduce unacceptable security and surveillance risks. Other critics assert that the problem is not with the apps but rather the manner of implementation, citing a slow, fragmented approach hampering US efforts to suppress COVID-19 or claiming that compulsory contact tracing technology would infringe on civil liberties.

As highly effective COVID-19 vaccines were developed and widely distributed in the United States by companies such as Pfizer, Moderna, and Johnson & Johnson by mid-2021, contributing to a significant decline in the number of cases of the disease, conversations around contact tracing methods and implementation were renewed among parallel reports of the national prioritization of vaccination efforts and an overall decrease in the usage of tracing apps. While some argued that such technology and a focus on contact tracing was largely no longer needed, others emphasized that the data attained from implementation of a combination of traditional and technological contact tracing would still be beneficial, particularly to learn more about cases in which those who were fully vaccinated still contracted the virus and whether they could still transmit it to others. By late 2021, another factor fueling debates around contact tracing technology was the identification of virus variants that ultimately proved even more transmissible, including the delta and omicron variants that had substantial impacts on case waves and influxes in the United States. Proponents of the technology argued for greater awareness of its supplemental benefits as well as its continued and increased use in not only helping to reduce the spread of these variants but also in gathering information about vaccination strategies. Meanwhile, others asserted that the applications, despite adjustments in some cases, remained too limited and ineffective, especially against variants that were spreading even more rapidly. According to the Washington Post, as of December 2021, nationwide usage of the Exposure Notifications System was still hinderingly low; at that point, over twenty states had not adopted it.

These essays and any opinions, information, or representations contained therein are the creation of the particular author and do not necessarily reflect the opinion of EBSCO Information Services.

About the Author

Joy Crelin is a freelance writer and editor based in Wethersfield, Connecticut. She holds a bachelor of fine arts degree in writing, literature, and publishing from Emerson College.

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