One of the most difficult parts of managing a pandemic is figuring out its path of transmission. Scientists rely on sophisticated computer models to predict the spread of disease on a macro level, but it can be extremely different to figure out the exact transmission pathway on a microlevel. That is why public health officials rely on contact tracing to chart and manage the transmission of disease.

Contact tracing is an effective method of containing the disease, but there are some complications with its real-world implementation. New technologies such as CareBand’s SafeTrack open up solutions for implementing contact tracing networks on a comprehensive and large-scale.

What Is Contact Tracing?

Contact tracing refers to disease control measures that consist of identifying persons who have come into contact with an infected person and gathering information about the nature of that contact. By tracing the path of contact, public health officials can identify, manage, and treat infected individuals, and manage further infections by figuring out who is likely to be infected.

The general idea of contact tracing is not exactly new. Throughout pretty much all history, humans understood that disease could come from contact with a sick person and that the incidence of disease could be reduced by limiting contact with the infected. During the Black Death in Europe, for example, people would place a red cross on the doorways of people known to be infected, as a means to discourage contact and figure out where the disease was spreading.

Contact tracing methods have become more sophisticated in the modern age, but the basic principle remains the same: The idea is to trace the spread of disease through the contact of individuals. Studies have shown that contact tracing can be an effective means of controlling the spread of certain infectious diseases and contact tracing is basically standard procedure for many public health organizations.

History of Contact Tracing

Contact tracing has existed in some form or another since virtually forever, but the greatest contact tracing success story is probably the eradication of smallpox. Contrary to popular opinion, smallpox was not eradicated just through a program of universal vaccination. Smallpox was eradicated through a rigorous process of contact tracing to chart the spread of the virus, quarantining and treating infected individuals, and immunizing the surrounding community at risk of contact.

To put some numbers on just how monumental of an achievement this was, Smallpox had existed since at least 1,000 BCE. In the 20th century alone, smallpox killed over 500 million people. In the 1950s, the Pan American Health Organization led the first hemisphere-wide attempt to eradicate the disease. The key to the eradication was a process known as “ring vaccination” which consisted of monitoring smallpox cases in a community and intervening for those who were at risk of infection. The WHO set up an international network of public health professionals who helped countries set up surveillance and containment processes. Thanks to these global and local contact tracing efforts, smallpox was officially declared eradicated in 1979.

Another example of the successes of contact tracing programs was the 2014 Ebola outbreak. In 2014, the largest Ebola outbreak in recorded history began in Western Africa. Contact tracing was part of a multi-pronged public health response that was successful in containing the spread of the virus after its initial spread. By monitoring contacts of infected individuals and preemptively managing those who had come into contact with the infected, global health agencies successfully eliminated the outbreak in Sierra Leone, the region that had been most affected by the crisis.

Why Is Contact Tracing Effective?

Contact tracing is effective simply because it intervenes in a crucial part of the disease transmission pathway. Contact with the infected is a major vector for several infectious diseases. Of course, for every type of disease, the relevant type of contact that needs to be monitored differs. For example, contact tracing for blood-borne diseases like HIV requires monitoring those who may have come in contact with the blood of the infected, while contact tracing for respiratory illnesses might involve monitoring those who live under the same roof who have been in close physical proximity of the infected.

Challenges to Contact Tracing

One of the difficult aspects of implementing contact tracing programs is setting up the right kinds of surveillance networks. For instance, one of the main challenges to contact tracing efforts aimed at containing Ebola was that public health agencies often did not have the trust of local communities, and so were not able to quickly and effectively deal with contacted individuals. Local communities were initially either unwilling or unable to follow WHO guidelines about contact tracing.

Another difficult aspect is gathering the correct information and ensuring people opt-in to contact tracing protocols. Stigma from disease makes many unwilling to participate in contact tracing schemes and privacy concerns about gathering information on an individual’s contact history is another major factor that can affect implementation.

The adoption of digital technologies can make the implementation of and adherence to contact tracing protocols more straightforward and manageable. Digital technologies offer a whole new infrastructure to build the monitoring networks necessary for successful contact tracing programs. Digital technologies and peripherals such as CareBand’s SafeTrack can utilize things like geofencing to gather data on people’s movements and contact history. This comprehensive data can then be used to determine at-risk individuals, monitor contact proximity, and trace the spread of infectious disease across a community/region. The main benefit is that digital technologies provide a decentralized network of data that updates itself in real-time so that public health officials have accurate and up-to-date information for managing outbreaks.


In today’s globalized world, new technologies are needed to combat the spread of diseases. Digital monitoring networks are one solution that allows public health agencies to handle contact-tracing in a highly interconnected world. Solutions like CareBand’s SafeTrack leverage low-power wide-area networks (LPWANs) to monitor contacts and enable autonomous contact tracing with sophisticated AI-based analysis that can detect early hotspots.