What Is Contact Tracing?

How does contact tracing work?

Contact tracing begins with the diagnosis of an infection. Testing labs, clinics, and hospitals report infections to the local health authority. The health authority then follows up with the infected person to try and identify people they have come into close contact with recently. Close contact is within 6 feet.

The health authority then contacts the individuals identified to warn them that they have been in close contact with a person who has tested positive with infection. The infected person remains anonymous.

These contacts may then undergo testing or, if they are already exhibiting symptoms, will be questioned about their own close contacts. The tracing process is therefore extended. Close contacts who can't be tested or who test negative are usually asked to self-quarantine for 14 days.

Why is contact tracing beneficial?

When contact tracing is conducted promptly and thoroughly, it can help slow or halt the spread of an infectious disease like COVID-19 by making people aware of their exposure to that disease.

Local health authorities can use the information gathered through contact tracing to decide whether to expand testing for an infectious disease, and to whom. They can also ask people waiting to be tested, or who have received test results, to self-quarantine if they have come into close contact with an infected person.

What is proximity analysis and tracing?

Locational data, gathered from Wi-Fi, Bluetooth, and mobile apps used in the workplace, can be employed to track the office population. The data identifies areas of contact such as group gatherings, as well as the duration and proximity of contact.

If an employee or visitor tests positive for an infectious disease that is being tracked, the employer can use proximity tracing data to alert people who had close contact with that infected person, and then institute testing protocols.

What are proximity-tracing protocols?

Proximity-tracing open protocols, such as Decentralized Privacy Preserving Proximity Tracing (DP3T) and Pan-European Privacy Preserving Proximity Tracing (PEPP), were developed in response to the COVID-19 pandemic.

These protocols establish procedures for collecting and disseminating data on COVID-19 infections. The data can then be used by public health and other officials for contact-tracing purposes.

The four basic steps of contact tracing

Step 1: Identification

When an infected person has been identified, through testing, as being positive for the disease, they are informed of their status. They are then advised to receive treatment, if necessary, and self-isolate.

Step 2: Collect information

Infected individuals are interviewed so that health officials can create a list of potential infections based on the person's recent close contacts.

Step 3: Locate close contacts

Close contacts are traced and notified that they have been in contact with an unnamed infected individual. The contacts are then advised to get testing and receive treatment if they are already exhibiting symptoms. They are also given instructions to self-quarantine.

Step 4: Monitor-traced individuals

Contact tracers keep in touch with traced individuals, reporting on temperature checks and symptoms, for 14 days after the person's last contact with an infected individual.

Types of digital contact-tracing tools

Proximity sensors

Proximity sensors are personal smart devices that can alert users by flashing, beeping, or vibrating if they are within 6 feet of another person with a similar sensor. These sensors can be inserted into ID cards, tiles, or key fobs carried by the user. Some sensors are inserted into devices about the size of a mobile phone and are worn by the user.

Some mobile phone apps can also act as sensors. In addition to delivering real-time warnings, these sensors can collect and transmit data that can be analyzed for contact tracing purposes.

Proximity-reporting applications and data

Proximity-reporting applications linked to Wi-Fi to office phones, mobile phones, and computers can trace where individuals have spent time in the workplace and for how long, revealing a path of potential infection that can be contact traced.

Some applications do not require a mobile app or additional hardware to use. But the key to many digital solutions for contact tracing is connectivity to Wi-Fi, Bluetooth, or GPS.

Connecting to these systems through a mobile phone or a sensor on the user can communicate location information, user density in a particular area, and duration of close contact back to contact-tracing applications or similar solutions.

Many digital tools that help support contact tracing can also be integrated with other solutions to allow for the creation of heat maps that show employers where and when employees tend to congregate in nonsocially distanced groups.

Proximity reporting that summarizes which individuals were in close contact with an infected person in a work setting can help businesses determine which areas to focus on for contact tracing and facilities cleaning.

Proximity reporting provides insights so organizations can plan workplaces that help reduce the risk of employees spreading an infectious disease, such as COVID-19. With these insights, employers can better comply with social-distancing guidelines and other health protocols to help prevent the spread of infectious disease.

Case-management software

This type of software can be used in the healthcare setting to capture infection data, initiate monitoring of infected patients, and reinforce manual contact tracing.