Twenty-five people are responsible for connecting the dots and collecting information across San Luis Obispo County for more than 2,000 local novel coronavirus cases.
Contact tracing is nothing new, but the novel coronavirus pandemic has brought it to the forefront of conversation about disease control and prevention.
“We mostly have all the work to do that nobody knows about,” said Kristin Edler, San Luis Obispo County’s senior public health nurse.
Edler, a contact tracer, has been working for the county for 18 years. She said the system that contact tracers use was put into place many years ago to address other communicable diseases, including hepatitis A.
Although the system was established, the COVID-19 pandemic has led to a need for more contact tracers, Edler said.
San Luis Obispo County now has 25 contact tracers working on a rotating basis, as opposed to five before the pandemic.
Edler said each contract tracer calls anywhere between 50 and 100 people a day, collecting information that is crucial to understanding the virus.
“Each case is unique and has its own set of circumstances,” Edler said. “There are cases where it just fits in a perfect box, but there’s nuance to most cases.”
Once a person’s COVID-19 test results are in, the San Luis Obispo County Health Department assigns each laboratory confirmed case to a contact tracer. A contact tracer then calls each person to let them know they are positive and to gather information about how they may have contracted the virus and who they may have given it to.
Once in contact, the county asks novel coronavirus-positive residents for information about their whereabouts in the 48 hours before the onset of their symptoms.
“Individuals are infectious 48 hours prior to becoming symptomatic, so we try to identify everywhere they’ve been, who they’ve been in contact with for the 48 hours prior up until that moment,” Edler said.
Edler dispelled rumors that the county attempts to reach everyone who has come in contact with a COVID-19 positive case within a 14-day period. For asymptomatic cases, she said, the county goes back 48 hours before the person getting tested, rather than 48 hours before symptom onset.
Edler also clarified that a contact doesn’t only mean anyone an infected person has seen in the past 48 hours. A contact is considered anyone who an infected person has spent 15 minutes or longer with within a 6-foot radius, she said.
“Just because you were all in the same (area), you know, if there were people at the table down from us, they wouldn’t be a contact,” Edler said. “There is certain criteria that have to be met to be considered a contact.”
According to Edler, if tracers identify that a person who tested positive has made close contact with others in the 48-hour window, they will reach out to the contacts and require that they quarantine.
The terms “isolation” and “quarantine” are often used interchangeably, but Edler said the two are technically different.
People who test positive for the novel coronavirus are ordered to isolate for a minimum of 10 days after the onset of symptoms. However, if their symptoms persist, then isolation can be required for longer time periods.
People who have come in contact with confirmed cases are required to quarantine for 14 days after being exposed to the coronavirus because the incubation period for the virus is up to 14 days.
At this time, San Luis Obispo County has asked that only symptomatic people and those who have been exposed get COVID-19 tests through the county’s free resources because of a backlog in testing results. Edler said that’s preferred even if contacts of confirmed cases wait to develop symptoms before they are tested.
“At day five (after novel coronavirus exposure), I could test negative, but that doesn’t mean at day 14 I won’t have converted over to positive,” Edler said. “Or day five, I might test negative because I don’t have sufficient viral load to produce a positive test, but that doesn’t mean that I necessarily won’t get sick by day 14.
“So we recommend you wait until symptoms start just based on our current testing.”
Along with contact information, tracers ask novel coronavirus-positive residents where they work and whether they were symptomatic at work. Edler said all employers are notified if one of their employees tests positive for the coronavirus. In some cases, she said, people, typically younger county residents, have multiple jobs.
Contact tracers also collect demographic information from novel coronavirus-positive residents, including race, age and where they live.
While the county shares most of that data on ReadySLO.org, race data have not been recorded on the county’s website.
“The information we collect is not just kept at a county level. It does go up to the state level,” Edler said.
COVID-19 Trends in SLO County
Paso Robles in northern SLO County has been a hotbed for coronavirus cases since mid-March. However, San Luis Obispo and Nipomo in the South County also have triple-digit case counts.
Echoing past comments by county public health officer Dr. Penny Borenstein, Edler said many San Luis Obispo cases have involved younger people, several of whom said they had been to bars and graduation parties before testing positive for COVID-19.
According to Edler, contact tracers have found that community spread is more common in those communities.
Multigenerational housing in Paso Robles and Nipomo is another trend that has led to increased cases, Edler said.
“We tend to see multigenerational family units, so a lot of people living in the same household are in those two areas of the county,” Edler said. “So, oftentimes they sound like a horrific amount of cases, but it might be that there’s 10 people in one house.”
Congregate-living facilities have also led to spikes in cases. Edler said the San Luis Obispo County Health Department works closely with the facility to identify all potentially exposed people.
Rising Case Numbers Pose Challenges for Contact Tracers
Since the end of May, Edler said the need for contact tracers has increased as the number of people connected to any given novel coronavirus-positive resident has grown.
“We’re seeing people who have a lot more contacts just because they’ve been out and about, they’ve had birthday parties or baby showers and bridal showers where they’re not practicing social distancing or mask wearing,” Edler said. “We’ve had as many as 30 contacts in some cases.”
In July, San Luis Obispo County contact tracers were faced with an increase in coronavirus cases and an increase in the number of contacts those cases had exposed to the virus, as well as slowed test results.
Edler said in some cases, by the time contact tracers were assigned a case, the person had fully recovered.
“It has eased a bit. Most of our specimens we are getting back, getting results quite a bit faster than they were,” Edler said. “There still are those outliers, though, that they are off isolation by the time we could actually even call them. We still see that, for sure.”
The county recently became aware that the state’s lab reporting system has had technical issues that may cause a delay in some case reporting, according to ReadySLO.org.
Edler also said contacting people is sometimes a challenge in itself. Occasionally, contact tracers will have difficulty reaching people because many younger folks don’t have voicemails set up, some people have international numbers, and others think the calls are a scam.
San Luis Obispo County has implemented new ways to reach people, including texting, during the past five months.
“It is a challenge, but we try other methods,” Edler said. “It’s definitely something we prioritize on a daily basis. If I couldn’t contact you one day, you would get a text the next day in addition to phone calls.”
As cases have continued to increase, contact tracers have moved to calling ongoing active cases every other day until they are considered recovered, rather than every day, according to Edler.
Edler said the increase in local COVID-19 cases has also caused investigations to be open for longer, leading to many cases being listed on ReadySLO.org as “under investigation.”
According to Edler, the county is often aware of the route of transmission fairly quickly, despite what the ReadySLO.org site shows.
Although there are many challenges to contact tracing, Edler said the community has been fairly proactive and most people they’ve reached out to stay home once they feel sick in any way.
“If we do call you or text you, please call us back. It’s most likely not a scam,” she said. “We really appreciate the community’s efforts to keep people safe.”
Read about contact tracing “disease detectives” in Santa Barbara County in this Noozhawk story by North County Editor Janene Scully.
— Cassandra Garibay is a reporter for The San Luis Obispo Tribune.