Contact Tracing: What Is It and Why Is It Important?

As state and local governments make plans to reopen parts of the economy, experts are calling for the deployment of contact tracing measures in order to track and slow the spread of COVID-19.

Contract tracing is one of the best tools available to slow the spread of infectious illness and has been used for everything from sexually transmitted diseases to Ebola. The World Health Organization says it should be the “backbone of the response” in every country.


But what exactly is contact tracing, who does it and how does it work?

In short, contract tracing is the process of identifying individuals who have contracted the virus and, in turn, finding and notifying all people they have been in contact with that are at risk due to significant exposure. Then, if possible, monitoring or quarantining those individuals or groups.

Cortex COVID-19 Contact Tracing for State and Local Health Departments

During this critical time, state and local agencies are making plans to widely expand their contact tracing measures. Cortex provides staffing and digital tool resources to help manage these efforts and ensure those infected and at risk are educated and/or recovering well. Learn more. 

How does contact tracing work? 

Before contract tracing can be effectively implemented, there needs to be certain resources in place. Namely, adequate testing and manpower.

Adequate testing remains a concern in the United States where experts say more tests are needed before tracing can be implemented to good effect. Secondly, there must be teams of contact tracers in place to identify, find and contact anyone who has been potentially exposed to the virus. The CDC recommends that state and local agencies expand staffing resources and use digital tools to expand reach and efficacy of contact tracers.

Here’s a basic overview of how the traditional contact tracing method works. 

1. Identification of infected individual

All individuals exhibiting symptoms of the virus should be tested, and some experts call for even broader testing of the population. In any case, once an infection is confirmed, the person is documented and asked to list all people they may have exposed to the virus. Proximity and length of exposure is taken into consideration. Generally, any exposure that was less than 2 meters distance and for longer than 15 minutes is considered a risk.

There are contact tracing technologies under development that automatically identify people who may have been exposed using Bluetooth beacons on mobile phones. This could remove the need to interview the infected person and automate much of the process but privacy remains the primary concern. 

2. Contacting individuals who are at risk

Next, each exposed individual is contacted and alerted to the risk. This person may then be asked to get tested and self-quarantine for a period of time (typically 14 days). If they are unable to do so, it may be necessary to provide them resources in order to complete a quarantine period. 

3. Contact follow-up

There should be regular follow-up with all contacts to monitor them for symptoms and test for infection. Follow-up is particularly important within the first two weeks after the exposure. It is during this time that the individual should carefully self-monitor for symptoms are refrain from contact with others. If the exposed individual does develop symptoms during this time, they may be tested for the virus. If they test positive, the process begins again with that individual.

How can technology enhance contact tracing?

Contract tracing at scale means keeping track of large amounts of data that needs to be secured. This is where technology comes into play.

To effectively conduct large contact tracing initiatives, data tracking systems will need to be used. These systems should be able to track a number of factors including:

  • Contact details of infected individuals, exposed individuals, and specific care providers 
  • Log of all contact from tracers
  • Log of any symptoms or confirmed infections
  • Success metrics on tracing activit

This system should be easy to use and efficient. Cortex provides digital tool resources like data tracking systems and necessary staffing to manage contract tracing efforts and ensure those infected and at-risk are educated and/or recovering well. Learn more. 

Automated contact tracing with Bluetooth technology

Until very recently, contract tracing has relied on the memory of infected individuals to accurately recall the places they’ve been and people with whom they’ve interacted. Its success also depends on having enough manpower to carry out all steps of the process. Today there are new advances in technology that can automate many parts of the system. However, they come with serious privacy concerns.

Contract tracing technology using Bluetooth beacons in mobile phones has been used in many countries, notably China, Singapore and South Korea, apparently to good effect. Typically, the technology is tied to an app that keeps an anonymous record of other phones it encounters. 

When a COVID infection is reported, the app uploads a record of their last two weeks of encounters. Range of distance and time are taken into consideration; for example, only phones which were within 2 meters for a period of longer than 10 minutes are selected. This information is then used to automatically message those individuals, alerting them of the exposure and the required quarantine.

Currently, Google and Android have developed such an app for use in the United States. However, there are concerns that the users’ information will not be kept completely anonymous which could result in negative outcomes such as data being sold to marketers or used in other ways without user permission. There are also concerns that infected individuals could be publicly “outed.” It remains unclear whether contact tracing apps will be used in the United States and/or to what scale. 

Cortex COVID-19 Resources for Healthcare Providers

During this critical time, state and local agencies are making plans to widely expand their contact tracing measures. Cortex provides staffing and digital tool resources to help manage these efforts and ensure patients are educated and recovering well. Learn more. 

Want to know how Cortex can help?