Case Investigation and Contact Tracing

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Reports from the front lines of Public Health

Over recent weeks, you have likely heard media reports that expanded COVID-19 testing, case investigation and contact tracing are the main tools in combating COVID-19. These efforts are also necessary to safely launch Governor’s Inslee’s phased Safe Start re-opening of Washington’s economy. You probably have an understanding of what is involved in testing, and may know that drive-thru testing has been launched in Skagit (click here for details). But you may wonder: What exactly is case investigation and contact tracing? I called Skagit County Public Health’s Community Health Worker Graciela Ibarra and Public Health Nurse Ian Capron to hear what it’s like to be on the front lines of these efforts.

What is case investigation?

Skagit County Public Health staff contact people who test positive for COVID-19 to provide important guidance and complete detailed interviews. Guidance includes how to safely isolate at home after testing positive or developing symptoms, as well as ways to access resources. Interviewing is a methodical process in which answers are pieced together to create a detailed history of where the interviewee has traveled, eaten, slept, and bathed. These questions focus on other people who may have had close contact with the person interviewed and who are at risk for COIVD-19 infection.

Asking personal questions, especially with someone you just met over the phone, can be a delicate process. Ian notes that people’s responses are “on a continuum.” Graciela adds that people “usually understand this is needed to keep them and others safe.” They may be hesitant to share the names of family members or coworkers. “We reassure them no one has done anything wrong. No one is in trouble or being punished.”

As you have likely concluded, case investigation requires a special skill set – a mixture of calm understanding and a steady focus on the goal of reaching all at-risk contacts. Investigators have to make certain that interviewees are heard and respected while ensuring that people who were possibly infected are identified.

What is contact tracing?

In contact tracing, the same investigation process is repeated in reaching out to those contacts who may have become infected as well. The number of contacts can add up fast and reside throughout the community. However, Ian notes, “Since Stay Home Stay Healthy began and people started physical distancing, the new cases and contacts tend to be in clusters within families or in the community at job sites of essential services.” One success of distancing is this narrowing of where exposures are occurring.

How do case investigation and contact tracing work?

Ian sums it up best: “Case investigation and contact tracing are our bread and butter. It’s the most proactive thing Public Health can do about COVID-19.”

One clarification before we go further: the difference between isolation and quarantine. Isolation refers to when a person separates themselves from others following a positive lab test or when they have symptoms consistent with COVID-19. Quarantine is for people who have no symptoms but have been exposed to the virus and could develop the illness in the 14 days after being exposed. Some people may quarantine and later become ill while others may not.

In short, case investigation and contact tracing:

  • Identify the spread of COVID-19 within the community.
  • Prevent further spread of COVID-19 within the community through reduced contact from people infected with the virus.
  • Provide people who are confirmed to have COVID-19 with guidance on how to successfully isolate so they can keep loved ones, neighbors and other community members safe.
  • Provide people who have been exposed to the virus with guidance on how to quarantine so they can help others stay safe.
  • Linkage to health care which can result in early diagnosis and care to those who need it.

High points and challenges in the day of case investigators and contact tracers

As you might imagine, the workdays of investigators and tracers might have several high points matched by ongoing challenges. The highpoints are obvious – at the end of each shift, public health staff know they have pushed backed against COVID-19 and prevented transmissions of the virus. They hear thanks from the public for the hard work and for keeping people safe.

The challenges tend to involve pre-existing issues affecting interviewees, such as lower income, a lack of resources and prior health conditions. These issues cause disproportionate hardship from COVID-19. Graciela describes a household in which ten family members live together but have only one bathroom, making risk of infection high and isolation all but impossible. Fortunately, Public Health is leasing a motel where people can isolate while other family members can safely quarantine, shortening the amount of time people are exposed to their sick family member. Ian points out that this temporary housing option enables “families to do the best they can” when facing COVID-19.  

Other difficult situations involve quarantine in which some household members work in critical infrastructure and can continue to go to work as long as they don’t have symptoms. Other people in the household have jobs that aren’t in these essential service industries. They cannot work during quarantine, even if they show no signs of illness. The difference in financial impact between those who are working and those who can’t seems unfair and can result in friction. This disproportionate impact is not unlike what is happening in our county and country overall, where the social distancing necessary to save lives results in harsh economic losses to some and little financial impact to others. Needless to say, working right in the middle of such a polarizing issue can be very difficult for investigators and tracers.

Skagit success

Early on, Skagit County Public Health realized case investigation and contact tracing was where it needed to invest its time and effort. The investigation/tracer team expanded quickly by cross training a large number of staff to do this critical work. Ian describes his co-workers’ efforts as “unbelievable,” as they set aside the work they were used to doing and took on a new job for the betterment of the community. This team enables Skagit to do a rare thing in Washington State – contact tracing not only with people diagnosed with COVID-19, but also with close contacts who have also developed symptoms (also referred to as probable cases). More contact tracing strengthens our outreach and ability to prevent spread. Skagit County Public Health also upped its outreach to businesses. Some larger statewide and regional employers have expressed great thanks, noting they had not experienced outreach from public health agencies elsewhere. Working directly with employers is key to promoting on-the-job safety for local workers.

A contact tracer’s advice

When I asked for what guidance they may have for the community, Ian pointed out that some people who later are diagnosed with COVID-19 “thought they just had allergies or a cold. Don’t ignore any symptoms, especially if they get worse,” adding, “but call your doctor first before you go in.” Graciela advises, “Listen to your body. See what it’s telling you. But if you are diagnosed with the virus, don’t let the disease take control of you. Look at media that is positive instead of all the negativity. Let yourself heal.”

More contact tracing info

Want more contact tracing info? Check at the Centers for Disease Control and Prevention webpage at: