WorldCoronaViras: Historical contact tracing data tracks the spread of COVID-19, but it’s not enough. Digital tools can help.
The goal of all contact tracing is to slow (and eventually stop) the spread of pathogens. This is done by identifying and notifying everyone who has been exposed to the pathogen so that the exposed person can be tested, self-isolate and prevent infecting others.

The method of contact tracing depends on the pathogen being identified.

In many cases, health care workers or contact tracers contact infected people, often by telephone, and interview them to understand contacts. This may be followed by a public announcement (for example, if a person infected with chickenpox is on a plane) or a private notice (if a person infected with a venereal disease is having unprotected sex).

Contact tracing is particularly important for pathogens such as SARS-CoV-2, which can spread even when infected individuals are asymptomatic. Drawing on experience in the fight against HIV, tuberculosis and other infectious diseases, countries and communities around the world have mobilized an unprecedented number of contact indicators – tens of thousands – to track the person-to-person spread of the coronavirus and alert the public. Who can be infected? Defenseless.

But even these historic efforts are leading to high transfer rates. In the United States alone, approximately 100,000 contact indicators are needed to meet the needs of the health care system.

Digital technologies, from smartphones to open source software, help fill the gaps.

Contact tracing goes digital

As health ministries and agencies adapt existing contact tracing systems to meet the needs of the COVID-19 pandemic, many are turning to digital tools to support their efforts. Existing tools such as text messaging and health information systems have long enabled contact tracing for infectious diseases, but outbreaks of this magnitude require robust tools designed for public health emergencies.

Some tools, such as the World Health Organization’s Go.Data platform or the SORMAS open source tool, are designed to support data collection and analysis in health emergencies.

Epidemiologists and contact identifiers use these systems to record information they gather during interviews, reports, and contacts with patients. In addition, contact tracers may signal the need for additional surveillance or outreach. Data from these systems will feed health leaders and epidemiologists to understand and visualize the spread of COVID-19.

This approach to digital contact tracing simplifies data collection, improves data quality and accessibility, and provides insights for faster decision-making. But digital technologies also create opportunities to create something entirely new.

Convert all your contacts into subscribers

In May 2020, Google and Apple released Exposure Notification, software that turns Apple and Android phones into contact tracers. Using Bluetooth technology, this software allows phones to “talk” to each other and register nearby devices. When a person reports a positive COVID-19 test result, every device they are in close contact with is notified of the potential infection. And this approach is used by other companies and software around the world.

This decentralized approach uses technology rather than human contact tracing to directly inform people of their potential exposure. People can decide more quickly whether to self-isolate or take other preventive measures. Data from these apps can also be used by health authorities to improve their traditional contact tracing programs.

System Limitations

Decentralized digital contact tracing has enormous potential, but that potential is undermined by potential risk and necessity. As this technology becomes more widespread, we must consider how its use widens the digital divide.

Health data is highly personal and sensitive information, and protecting that data is the foundation of successful digital healthcare. Combining health, demographic and location data on one platform increases the potential risk. For this reason, privacy, security and trust should be at the center of these tools.

These apps need to be actively used by at least 60 percent of the population to be most effective. But more than 4 billion people still do not have access to mobile Internet services, so creating a contact tracing system based on Apple, Android and other smart devices leaves entire communities behind.
Many of these decentralized applications rely on individual reporting.

Instead of triggering tracking by a trained and paid third party, people should be willing (and remember) to report COVID-19 positive tests to the app. Users of these apps ensure that other users report their positive tests.
These applications do not replace the need for resources and information. When someone is notified of a potential exposure, they need to understand what that exposure means to their risk of contracting COVID-19 and what to do next.

Proper use of this technique is very important. Digital contact tracing is an important tool for future disease outbreaks, and less time is wasted now during the next public health emergency. And while we want to use all available tools, we must apply these methods in a way that overcomes the odds, not the other way around.