Contact tracing and our cautious first steps out of the lockdown
by Yasir Aheer, Varun Rao, and Rahul Rao
Summary:
Contact Tracing will play a major role as we slowly open our society and economy. It is a specialised field with trained professionals, and we just don’t have enough of them to cope with the current pandemic.
Digital and mobile technology solutions, in the form of tracing apps, have been hailed by some as technological saviours. However going digital is not a panacea for all ills - contact tracing apps have their own set of challenges and open up a host of privacy concerns.
There has been much debate around the centralised vs decentralised approaches to data management. A single entity has control over all the data in a centralised model, while data is spread across different devices in a decentralised model. Transparency and security will be paramount to all aspects regarding the data.
Time is of the essence and there is a sense of urgency to get a solution out there, however a considered approach is needed together with transparency to nurture trust and encourage adoption.
Over the past few months, several epidemiological terms have entered the common vernacular. Terms like “flattening the curve” and “social distancing” are now ubiquitous. As we look for ways out of the lock-down, another term has also gained traction: “Contact Tracing” - an approach to contain infectious outbreaks. Contact tracing is a lot like detective work; meticulously identifying all individuals with recent exposure to a confirmed case, notifying those contacts and then subsequently monitoring their symptoms. World Health Organisation (WHO) defines the process of contact tracing as three sub-steps:
Contact Identification: Interview recent patients and help them recall everyone they may have come in close proximity.
Contact Listing: Notify all individuals of their contact status. Share important information regarding the disease such as symptoms, along with further measures such as self-isolation and quarantine.
Contact Follow-up: Continue follow-up to monitor for symptoms and assess whether further tests are required.
Contact tracing has been used in the past against SARS in 2003 and with the Ebola virus in 2014. This time, however, technology has been deployed at hitherto unimaginable scale to assist with contact tracing and other prevention measures. As an example, China has leveraged technology at unprecedented levels, from using mobile GPS tracking to identify high risk individuals, to deploying helmets that can measure people’s temperature within a 5m radius, sounding an alarm if suspected of fever.
Contact tracing will play a major role as we cautiously open our society and economy. Where possible governments are employing proactive approaches of logging potential contacts. The state of Victoria now requires cafes and restaurants to maintain a Visitor and Patron Contacts Log. The intent is to keep a record of visitors at venues where people congregate in relatively close quarters. This information will assist government agencies and contact tracing professionals to identify exposed individuals when a patron later tests positive.
However, such approaches are manually intensive, slow, and will clearly miss many other random contacts on the street, public transport etc. Lori Freeman, CEO of the National Association of County and City Health Officials (U.S.) estimates that 15 contact tracing professionals are needed per 100,000 population in non-emergency situations, and that the required number would at least double during a pandemic. Prior to the recent pandemic there were only an estimated 2,000 contact tracers in the US. Ramping up to the number of contact tracing professionals needed for over a short period is not feasible given the specialised nature of the profession.
Digital and mobile technology solutions, in the form of tracing apps, address these gaps and have been hailed by some as technological saviours. Several contact tracing apps have emerged, the most high-profile one developed in a collaboration between Apple and Google, called Exposure Notification. The technology underpinning most apps is straightforward, as illustrated in Figures 1 and 2.
When a user comes in close proximity to another, the app uses Bluetooth to connect and exchange unique keys, storing the interaction for a specified period. Individuals who later test positive can voluntarily update their health status on the app, which in turn notifies all individuals that have been in close contact.
However going digital is not a panacea for all ills - contact tracing apps have their own set of challenges and open a host of privacy concerns. Firstly, it appears that the underlying technology and hardware is being stretched as it is applied to an unintended use-case. Singapore’s TraceTogether app has been plagued by technical issues. The app needs to be in the foreground in an unlocked phone for it to work properly, which has battery usage implications. Its App Store page is littered with claims that users were unable to make phone calls when allowing the app to function properly.
Secondly, there are deep concerns around privacy given the sensitive nature of the data collected, such as various forms of Personally Identifiable Information (PII), location, interactions with other individuals and, of course, the health status of individuals. While there is a need for urgency, a considered approach is required when dealing with data as sensitive as people’s identity, behaviour and health. There has been much debate around the centralised vs decentralised approaches to data management. A single entity has control over all the data in a centralised model, while data is spread across different devices in a decentralised model. Transparency and security will be paramount on all aspects regarding the data. Some of the questions that most users would be interested in include: Where is the data stored, i.e. how much is locally stored in the user’s hand-set vs elsewhere? How long will it be retained for? Who will have access to the data? How will anonymity be ensured for people testing positive?
Thirdly, everyone within a region would need to use the same platform for the approach to be effective. With several apps in development or published, the approach only works if people who come in contact with each other are using apps that can communicate. From what we understand, the current versions available in the market do not have capability to interact with other apps. This could have implications for travel, both domestic or international. As an example, some states in the U.S are using different platforms. Utah has developed Healthy Together, North Dakota uses a different app called Care19, while other states are exploring to leverage Exposure Notification platform developed jointly by Apple and Google.
Lastly, experts at Oxford University estimate that 60% of the population need to be using any single app to be effective. Such volume of adoption might be achievable in authoritarian societies that can mandate usage, however may not be possible in liberal democratic societies. For example, the Australian government’s COVIDSafe contact tracing app may not meet its comparatively modest target adoption rate of 40%.
None of these are insurmountable problems though. Time is of the essence and there is a sense of urgency to get a solution out there. However, the “Move fast and break things” mantra may not be appropriate for solutions where lives are at stake. A considered approach is needed together with transparency to nurture trust and encourage adoption.
Co-Authors:
Disclaimer: This article is based on our personal opinion and does not reflect or represent any organisation that we might be associated with.