Phone Application Use in Contact Tracing for COVID-19
Anas Rihawi, MD, MPH Candidate, Kristen Trimble, MSN, APRN, Andrew J. Keady, MBA, JD Candidate
Tuesday, June 9, 2020
Most countries, including the United States, have implemented stringent social distancing initiatives to mitigate the spread of coronavirus disease 2019 (COVID-19) and ease the burden on healthcare infrastructure. However, such efforts are not sustainable on a long-term basis, and further guidance is needed while easing social distancing measures to avoid additional spikes in the pandemic. Rapid identification of new COVID-19 cases and sufficient contact tracing to isolate and treat the exposed is the mainstay currently when prophylactic treatment or vaccination is lacking. Contact tracing has proven beneficial in infectious disease transmission control for decades and through multiple diseases. Significant implementation of contact tracing was done in recent years to contain SARS, MERS, Ebola, and now COVID-19. It is estimated that contact tracing can reduce the detection and isolation of infected individuals by two days (from 4.6 days to 2.7 days in a study) (1). Considering the high infection rate of COVID-19, especially in asymptomatic people (each infected person can infect 2-3 people), early detection and isolation are vital to reduce the rate of transmission (2).
We learn methods for the identification of infected and exposed individuals by looking at experiences in dealing with previous outbreaks and comparing them to other countries. During the outbreak of SARS, for example, the Taiwanese government established a National Health Command Center (NHCC) that is a part of a disaster control system specifically designed to control health, infectious outbreaks, and disasters. This center was activated when the COVID-19 pandemic started. Screening and identification of at-risk and infected individuals coming from high-risk areas such as China and within the country were implemented. As a result, the Taiwan Center for Disease Control reported a total of 443 cases in the country as of June 3, 2020, which is one of the lowest total cases reported in a country globally (3). Other countries, such as Singapore, South Korea, Iceland, and New Zealand, implemented rapid and significant efforts which resulted in effective control of the spread of the virus (4–7). As of June 8, 2020, New Zealand has been able to remove its restrictions after reaching zero cases of active COVID-19 (8).
The Center for Disease Control (CDC) established guidance to aid entities such as states, localities, and organizations to implement contact tracing. A framework of interventions was suggested to cover different aspects of the approach: 1) Tracing infected people and their contacts, 2) Supporting infected people and their contacts in quarantine, 3) Increasing the workforce of contact tracers, 4) Implementing digital strategies (9).
Contact tracing is done by detecting whom the infected person encountered during the infectivity period. This procedure is achieved in multiple ways. The traditional method for contact tracing involves interviewing and questioning the infected person to find out whom they came in contact with before the time of diagnosis. While contact investigation by interview is a fundamental first-line method, it can lack efficacy due to recall bias (forgetting). Contact tracing by questioning has been critical in tracking many diseases such as tuberculosis and HIV (10,11); however, COVID-19 has an insidious onset, and symptoms vary widely. Therefore, recall can be a significant barrier. Also, other potential obstacles can limit the effectiveness of interviewing such as language barriers, cultural differences, communication barriers (either due to lack of communication skills or communication impairments such as changes in mental status due to illness or other reasons, dementia, etc.), among others. Finally, infected individuals may feel hesitant about divulging personal details about their whereabouts to another person.
Traditional contact tracing also requires a large workforce and need to increase capacity in the current situation. It is estimated that between 4 and 81 contact tracers are needed for every 100,000 people in the population-based on previous experiences (2). It is also estimated that for the population in the US, a new 100,000 contact tracers are at least needed to cover the needs of the US population (2). The requisite need for personnel will add a significant funding burden and will require training and skills. The current capacity in most of the states falls behind the proposed need, and many states have no current plans to increase the workforce (12,13). Funding for contact tracing is currently ongoing but may, nonetheless, fall short. Further, regulations and bureaucracy might delay funding and application (14,15).
Using Technology for Contact Tracing
Multiple approaches augment traditional contact tracing applied in the past and are options to consider during this current pandemic. For example, during the initial outbreak of COVID-19, parts of China used extensive mobile network searches to identify people at risk to test them (16). This method was noted to be helpful in the initial phase, but it is challenging to implement given privacy concerns. New Zealand used a multi-system approach that used web-based and cloud-based services to report and store infected and exposed individuals to aid a National Close Contact Service (NCCS) in contacting individuals and ensure proper testing and quarantine (17). This method proved to be very beneficial in the specific situation of New Zealand. Taiwan, through its National Health Command Center (NHCC), used mobile phone tracking systems for infected individuals and used a “health declaration” application by using SMS and QR codes for incoming travelers (18). The South Korean Center for Disease Control and Prevention used a multi-level approach to identify contacts of infected individuals by obtaining health facilities and pharmacy records to estimate the infectious window of the individual, then relayed on GPS data, credit card transaction records and CCTV to track potential exposures that the patients might have failed to identify (19). Many countries implemented toll-free hotlines that people can call to self-identify or when there is a potential exposure (20,21). Using more complicated technology, such as contact tracing mobile applications, is currently a rising potential to combat the disease. This method was used previously in pilot studies that showed benefit in the detection and follow up of infectious diseases (22). Multiple countries initiated and piloted different application platforms for disease tracking and detection. For example, Singapore launched the TraceTogether mobile application, which is free to download and voluntary (23). Other countries are testing and implementing different platforms, as well (24). In response to the pandemic, Apple and Google launched platform services for governmental agencies to develop applications (25). Currently, in the US, multiple states are considering different mobile application methods, such as in Massachusetts, with the help of various private and educational entities, including the Broad Institute (24).
Drawbacks of Contact Tracing
In addition to the many benefits of digital contact tracing, there are also several concerns. Identified concerns may include privacy, accuracy, equity, and misinformation. Sharing identifiable information about individuals who have COVID-19 can lead to stigma or blame. For instance, businesses in China and South Korea lost business after the identification of a positive case in their stores (26). However, the crisis has shown that social shame is effective at changing risky behaviors that may spread infection along with discouraging businesses from defying local infectious disease ordinances. People are also concerned about the government being able to know where they are at all times. For example, in China, people who are believed to have come in contact with someone who tested positive are not allowed to enter public spaces, shops, or use transportation (27). Citizens may find it deeply unsettling to have a government be able to dictate much of their lives. Furthermore, the Israeli government tracks individuals using cell phones for an anti-terrorist program, which allows for monitoring the majority of the population and can be used to enforce self-isolation (27). Another aspect of using digital contact tracing is the accuracy in the application to catch close contacts adequately. This would be especially challenging in large crowds and on public transportation (28). There is also a risk of false positives due to unreliable, biased, or non-transparent algorithms (27). Interestingly, individuals who are identified as being in close contact with a person with a positive COVID-19 test may be non-compliant with quarantine recommendations. If governments were in possession of information indicating a person was disobeying quarantine recommendations, the person may face repercussions. Government repercussions may lead to decreased use of voluntary contact tracing applications. In regards to equity, the elderly, homeless, and low-income individuals without access to technology may not be able to participate if they do not have a smartphone (26). These populations are already more vulnerable to COVID-19, and it would not be fair not to be able to include them in contact tracing due to the lack of a smartphone. There is not a readily ascertainable solution to solving this inequity. Lastly, the results of the application may be misinterpreted or otherwise misconstrued. Those receiving no alerts may have a false sense of security, believing they are not at risk for COVID-19 (26). Those who do receive an alert may panic or think this means that they do have COVID-19 (26). An improperly informed user base for the application may negate the effectiveness of the contact tracing application. Additionally, there is concern regarding the widespread use of contact tracing applications. There appears to be a threshold number of the population that must participate in the use of the contact tracing application to be thoroughly effective.
The fight to contain and prevent further spread of COVID-19 remains in its early stages, despite the amount of time that has passed. Given the prediction of future outbreaks and lack of population immunity, it is crucial to continue to innovate to find the most effective and acceptable method to limit the spread of COVID-19. Moreover, predictions of future outbreaks being more widespread make the use of infection mitigation methods a more pressing concern. Using a contact tracing mobile application appears to be a promising method to efficiently and accurately identify those who need to quarantine after being in close proximity with an individual with COVID-19. However, the development and implementation of contact tracing are not without potential ethical and technological problems. Developers of applications must be aware of these possible issues when implementing a mobile application. The understanding of COVID-19 is also significantly growing overtime. As technology is used to augment contact tracing during this pandemic, it is essential to frequently assess the accuracy of the application and remain flexible to be able to update it when new, applicable information becomes available. Failure to update contact tracing technology with new medical evidence may result in the application failing to fulfill its purpose or may lead to increased infection spread. The New Zealand, Taiwanese, and Korean approaches are all government-heavy approaches that, while accepted culturally in their respective countries, may receive push-back in countries such as the US. Given the US citizens’ skeptical nature of the government, a strong push into creating contact tracing applications may face adoption challenges. Thus, expecting widespread voluntary adoption of contact tracing technology provided by state governments among US citizens may be unlikely. State governments should focus on public-private partnerships that ensure privacy. States can implement public-private partnerships where user data and privacy are ensured, while still leveraging public health resources such as public health departments. Creating public trust in contact tracing applications deployed by state governments will likely require informing the user base on how data is used, collected, and implemented. Forming trust with disenfranchised populations and the general population is essential to any public health initiative but especially with regards to attaining widespread use of a contact tracing application. Nonetheless, contact tracking technology may be immensely beneficial because it can be formulated to be more precise (using Bluetooth technology) and unbiased algorithmically if deployed correctly.
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