Understanding contact tracing in the effort to contain COVID-19

Over the past weeks, one of the terms that has become important in the effort to contain COVID-19 is contact tracing.

So, why is it important and how does it fit into the COVID-19 picture?

State Health Officer Dr. Thomas Dobbs considers contact tracing vital to containing the virus in Mississippi.

“It’s a hugely labor-intensive effort to make sure you find every case and that you have eyes on them to make sure they’re properly isolated,” Dobbs said last month during a news conference outlining his plans. “But from there, we want to do an intensive contact investigation to identify that second tier of individuals who are likely to be the next generation of infection and make sure they understand their quarantine obligation to make sure it doesn’t spread beyond that level.”

Contract tracing isn’t new. Virologists and other researchers into contagious diseases—from measles, polio and tuberculosis to AIDS and Ebola—have long used the method in their attempts to shut down or minimize further contagion.

The concept is simple: Find the people who have been in contact with an infected person and isolate them to stop further contagion.

Implementing contact tracing isn’t as easy as it sounds. For every person infected, researchers help the patient to recall everyone they have been in contact with during the timeframe they may have been infectious. For COVID-19, that timeframe is at least 48 hours before the onset of symptoms, according to the Centers for Disease Control and Prevention.

Researchers then reach out to each of those contacts to let them know they may have been exposed. Without revealing the identity of the infected person (prohibited by federal laws), contacts are provided with information and support to understand their risk. They will be asked to self-quarantine and monitor themselves for any signs of disease for 14 days from the time of contact.

To be effective, researchers will monitor each of the contacts throughout the process.

Contract tracing requires a large number of trained researchers and a large budget to carry out in even a small population. In Mississippi, where more than 5,000 cases have been confirmed, contact tracing could reveal an exponential number of contacts who are potentially infected without knowing it.

And that is where social distancing and hygiene come into play. The fewer close contacts infected people have, the fewer numbers of cases and deaths from the virus.

On April 23, U.S. Sen. Cindy Hyde-Smith announced that Mississippi will receive more than $6.5 million “to build its COVID-19 testing, contact tracing, and containment capacities.”

“Effective containment of the coronavirus will rely on more testing and tracing,” Hyde-Smith said in a statement. “The CDC is providing resources to states to use public health systems to accelerate this process, which will help move us to a point where we can safely reopen our economy.”

For more information on contact tracing, visit the CDC website.