Reviewed by: Darlene Bhavnani, MD, Epidemiologist
Written by: Lauryn Feil
While there is no vaccine or proven treatment method (yet) for COVID-19, certain measures have been shown to help slow the spread of the disease across populations. By now you’re probably an expert in social distancing, which encourages people to limit their physical interactions with others to stop the spread of the virus. And you’ve likely heard of contact tracing, another powerful tool used to separate those who have been in contact with a COVID-19 case and are thus, at high risk of having the disease themselves.
We’ve seen proof that social distancing is effective in reports from UT Austin’s COVID-19 Modeling Consortium, where researchers continue to project a steady decline in COVID-19 related deaths. But what about those who may have been or currently are in contact with someone who has a confirmed diagnosis of the virus? This is where contact tracing comes in. The success of relaxing stay-at-home orders and social distancing policies may depend on our ability to effectively carry out the efforts of contact tracing on a larger scale.
But what exactly is contact tracing, and how does it help society battle infectious diseases? Here are the basics of this time-tested public health strategy and what you can do, starting now, to help your community in the fight against COVID-19.
What is contact tracing?
Outside of an epidemic or pandemic, contact tracing is routinely used to control the spread of infectious diseases such as tuberculosis and sexually transmitted infections. It starts with a known or suspected case, known as the “index case.” Trained community workers interview the index case to trace back who they may have had recent contact with, including family, friends, coworkers, neighbors and more.
Then, those people who may have been exposed are contacted, interviewed about their symptomatic status, provided testing recommendations, and, depending on the disease, are encouraged to refrain from contacting others or seek treatment to prevent further spread. Of those contacts tested, if there is a new confirmed case of the virus, the process of contact tracing continues.
If a contact does not show signs or symptoms of the disease, they will still be monitored for the duration of the disease’s incubation period, which for COVID-19 is 14 days. The process continues until all potential cases (in a perfect world) are identified.
How does contact tracing work to slow the spread of disease?
Contact tracing is a very lengthy process that requires many steps, but when done successfully, it can interrupt the ongoing transmission of a disease and reduce the spread of infection. Contact tracing helps catch and control new outbreaks before they are able to grow, effectively stopping the disease in its tracks.
When deployed early enough, contact tracing can often make a difference in the dynamics of an outbreak. As in the case of South Korea, whose rapid response involved enhanced testing availability, safe COVID-19 medical facilities, and a government-run, technologically advanced contact tracing system. South Korea was able to lower the number of new infections from 851 on March 3 to 11 infections as of April 21. Their mortality rate from COVID-19 hovers around 2%.
Data gathered from contact tracing also helps epidemiologists learn more about a disease and its transmission in a particular population, which is used to track impact regionally, nationally, and globally. Enhancing contract tracing funding and efforts can help keep communities safe from outbreaks and death rates low.
What are the limitations to contact tracing?
For contact tracing to be most effective, there needs to be an abndance of tests and contacts need to be tracked, notified, and tested quickly. It often works best with low levels of infection within an isolated population. During the current COVID-19 pandemic however, widespread infection has already occurred, the United States is lacking in trained staff or volunteers to carry out contact tracing efforts, and there are national shortages of COVID-19 tests, which can make contact tracing extremely difficult. Take New York City for example, its uniquely dense population and the lack of available tests contributed to the rapid spread of the virus across the city and state (New York state reported between 8,000 and 10,000 new cases each day between March 31 and April 12).
There are also concerns surrounding the fact that some individuals may be asymptomatic, or not show signs of infection, and may spread the disease without realizing it. Apple and Google have announced a plan to turn phones into opt-in COVID-19 tracking machines that will make it easier to identify and alert people if they’ve been exposed to the virus. But, while technology can help, privacy concerns among citizens remain and public health experts say these tools won’t eliminate the need for thousands of new workers.
Despite the above limitation, cities and communities will still benefit greatly from ramping up contact tracing efforts as we progress toward, hopefully, slowing and eventually stoping the spread of COVID-19 until a reliable treatment or vaccine is produced. These programs will also serve as the foundation for future guidelines on contact tracing if another outbreak occurs.
How can you help?
While only time will tell how states perform as they begin reopening businesses and lifting social distancing policies, contact tracing may be the key to managing COVID-19 flare-ups. According to a recent survey done by NPR, Texas does not meet the estimated need of contact tracers based on our state’s population.
UT Health Austin and the Dell Medical School are looking for volunteers interested in helping with contact tracing and home monitoring. These individuals will collect valuable data and make a community impact by helping slow the transmission of COVID-19. If you interested in volunteering, please visit here.
If you are unable to volunteer, there are still ways you can help at home. If you do happen to come in contact with someone who has been diagnosed with COVID-19, you may be contacted and notified by a contact tracer. And since your chances of infection may be higher, it’s a good idea to share a current list of your whereabouts from the last 14-16 days. Where you went and who you came in contact with can be challenging to recall, so you can be proactive by keeping a record of your daily activity and the individuals you have been in contact with by filling out this self-tracing sheet. Close contact is defined by the CDC as less than six feet away from someone for more than 15 minutes.
As always, please continue to follow the latest CDC recommendations, wash your hands frequently, and seek out medical attention if you start experiencing symptoms of COVID-19. For the latest COVID-19 updates from UT Health Austin, visit here.