Whatcom County, state struggle with contact tracing as COVID-19 cases surge
A key strategy in fighting the spread of COVID-19 is reaching people early who have been infected and then contacting anyone they might have subsequently infected.
The processes are called case investigation (the process of reaching someone who is infected) and contact tracing (reaching people who might have been exposed to the infected person). Local health agencies across Washington, as well as the state Department of Health, have been using those processes since spring when the coronavirus began its march across the state.
In case investigations, it is the state’s goal is to make contact with 90% of infected persons within 24 hours of the state health department receiving a positive lab result.
In contact tracing, it is the state’s goal to make contact within 48 hours with 80% of people who were exposed to that person.
The targets for case investigations and contact tracing in a November report are 90% of cases reached within one day of receiving a positive lab result, and 80% of contacts to be reached within two days of receiving a positive lab result for the case.
Both Washington and Whatcom County are struggling with those targets.
A Department of Health report released Nov. 25 showed it was reaching a smaller percentage of infected people within one day of receiving a positive lab report than it was in October. It also was reaching a smaller percentage of initial calls to their contacts.
State metrics and performance
According to the state Department of Health’s measurement metrics, reaching an individual includes a phone call outcome of: interview completed, partial interview completed, call back later, or refused.
For contacts, being reached also includes confirmation that a text message notification was received.
As for case interviews, the health department measures that as “a phone call that results in a full or partial interview. For contacts, their contact information is only collected during the case interviews. If DOH is unable to complete case interviews, their contacts are not reported to DOH.”
For case investigations, the percentage of total cases with a first attempted call within one day dropped from 84% the week of Oct. 18, with 485 cases assigned, to 11% the week of Nov. 8, with 2,787 cases assigned to the state.
In that same time frame, the state reached 61% of cases within one day the week of Oct. 18, and just 6% of its assigned cases by the week of Nov. 8.
The percentage of total cases interviewed within one day of a positive lab report in the same time frame dropped from 52% to 5%.
The next step, contact tracing, shows a similar decline amid rising cases except in one area: percentage of total contacts interviewed, which increased from 82% the week of Oct. 18 to 86% the week of Nov. 8.
The percentage of total contacts with a first-call attempt within two days declined from 90% the week of Oct. 18 with 540 cases assigned to 22% the week of Nov. 8 with 2,719 cases assigned.
The percentage of total contacts reached within two days in the same time frame dropped from 73% to 19% and percent of total contacts interviewed within two days dropped from 67% to 17%.
What the state says
The state Department of Health argues its success rate is actually higher now than in October if the 24- and 48-hour deadlines are discarded.
Based on a 14-day quarantine period, the state investigated 73% of cases it was assigned and reached 86% of contacts the week of Nov. 8.
In November, it took the state an average of 3.27 days to reach a person who tested positive for COVID-19, and it took an average of 3.37 days to reach close contacts.
State health department points to various roadblocks to reaching people.
According to its November report: “The most common barriers to successfully meeting these deadlines include missing phone numbers or other contact information and people who require additional follow-up due to an unanswered first call.”
The state also notes that the current surge came sooner and is larger than anticipated.
“It arrived earlier,” said Maayan Simckes, a state epidemiologist and case and contact tracing training lead, in an interview with The News Tribune. “And it’s moving faster than we thought.”
The state had been building up its investigation staff in anticipation of the surge, she said, but it wasn’t enough. Caseloads are now doubling every two weeks, compared with four weeks in April.
The state had 150 case investigators on Nov. 16, according to spokeswoman Teresa McCallion.
“Our goal is to ramp up to 700 case investigation and contact tracers by mid-December to meet our goal of 400 daily investigators,” she said. The state conducts investigations seven days a week.
In addition, the state brought back 100 National Guard personnel this week to assist in the effort, McCallion said.
While it’s up to county health departments, tribal health authorities and others to conduct their own investigations, the state Department of Health has staff that can pick up cases when those local agencies are overwhelmed, Simckes said.
Whatcom County
The Whatcom County Health Department also has struggled to contact people because of a dramatic jump in new cases since mid-November.
”For instance, in the two weeks between Nov. 20 and Dec. 3 confirmed cases increased by 562, from 1,983 to 2,545,” Amy Cloud, spokesperson for Whatcom Unified Command, said to The Bellingham Herald.
The health department has 40 employees and volunteers trained to do such interviews.
Its one-day completion rate on case interviews was consistently above 90% before the first week in November, Cloud said.
The completion rate dropped to a low of 75% at the end of November despite help from the state Department of Health, she said, adding that it is back on the rise as of last week.
“Anecdotally, the increase in cases and contacts has increased the workload on our dedicated team of case and contact investigators,” Cloud said. “They aren’t always able to reach individuals on the first few attempts, which means time spent on ‘phone tag.’ Unfortunately, as volume increases, it takes longer and more attempts to reach people.”
She said officials continue to recruit more volunteers for such efforts.
Making contact
Case investigation looks backward and contact tracing looks forward, the state’s Simckes said. The goal is to see where the infection came from and determine where it might be going.
In that initial 24-hour period after a positive test result, staff attempt to call people with the virus four times. The calls are spread apart by four hours. That can span over two to three days, depending on the workload.
For contact tracing, three calls are made. Voicemails are left and text messaging also is used.
The public is under no obligation to speak with the department of health, and some people don’t, Simckes said.
“Our ability to actually reach them is dependent on if they answer the phone or if they answer our text,” she said.
Some people, when contacted, refuse to cooperate with staff, Simckes said.
While a major focus of the case investigation is to get contact information, the goal in contact tracing is to let people know they might have been infected and to take the appropriate countermeasures. Namely: quarantine.
Quarantine and isolation
Quarantine might conjure images of sailing ships unloading sick passengers, but it’s actually a cautionary practice for those who aren’t showing symptoms of a communicable disease. Staying in quarantine is what health officials would like those identified as contacts of positive COVID-19 cases to do.
If a person has been exposed to someone who is known to have COVID-19, they should not then expose themselves to anyone outside their home for 10 days after the exposure or seven days following a negative test result. That usually involves staying home for the full duration and staying away from anyone within the home who might be at risk for getting very sick from COVID-19.
Even if they are not symptomatic, Simckes wants contacts to “follow the right public health guidance to make sure they don’t continue spreading it beyond them. And if I can cut the chain, then the cases won’t spread, we won’t have more infection.”
If a contact does develop symptoms of COVID-19, they are asked to isolate. Isolation is more restrictive than quarantine and involves the infected person maintaining a safe distance from other people — even those living within the same household — for at least 10 days after symptoms appeared. The person should use a bathroom and “sick room” dedicated only to them. Isolation should only end when the person has been fever-free for at least 24 hours and symptoms have improved.
State investigators report that Washington residents are eager to help, Simckes said.
“And only on rare rare occasions are they facing strong resistance,” she said.
Cases and contacts do react differently, she said. People who have tested positive have probably already received notification from their health care provider. With contacts, the first time they are hearing about a possible exposure might be from health department staff.
“There’ll be a bit more confusion, surprise and concern when speaking to a contact who isn’t aware that they were exposed to somebody who had COVID,” Simckes said.
If the health department has a contact’s cell phone number, that person might receive a text message informing them of the exposure before a call is made. That can make the first contact go smoother.
“We see folks who initially refuse to do an interview,” Simckes said. “And then they do some research, and they call us back, and they say ‘I changed my mind. I want to participate. And I want to help out my state.’”
This story was originally published December 6, 2020 at 5:00 AM.
