B.C.’s army of contact tracers ready to battle virus
Over 270 people investigate cases in Vancouver region
VICTORIA — B.C. has ramped up the largest public-health effort in its history to track down and contain cases of COVID-19 as schools reopen and people slowly expand their social networks.
The province now has more than 550 communicable-disease investigators to conduct what’s known as “contact tracing” — rapidly identifying people who test positive for the virus, figuring out who they might have spread it to, and trying to stop outbreaks from expanding through the community.
In Vancouver Coastal Health, the 12-person team of contact tracers that existed before COVID-19 has ballooned to more than 270 people. They are scattered throughout the region, but trained and ready to go at a moment’s notice, said Dr. Althea Hayden, the medical health officer who helps oversee the team.
“There’s a long history of explaining public health investigations, including contact tracing, as a kind of detective work,” she said. “You talk about gumshoe epidemiologists getting out in the field and that kind of thing.”
Fraser Health’s team of 14 contact tracers has grown to more than 250 people, said Aamir Bharmal, medical director for communicable disease and harm reduction. At Island Health, it’s up from 10 to 35 people.
“Given the absence of any treatment for COVID-19 to prevent onward transmission, or a vaccine, contact tracing is just so pivotal in terms of a response,” Bharmal said. “It’s about identifying how someone got COVID, but also who did they expose.”
Time is of the essence, because COVID-19 cases can double in a community within two to three days, Bharmal said. If a person can’t be reached by phone, other health teams and sometimes the police are used to help track them down.
“Very quickly, a small cluster can become a much larger outbreak,” Bharmal said. “Once we’ve identified a case, we’re ideally trying to stamp out that ember so it doesn’t become a bigger fire.”
There are not currently enough new cases to keep the hundreds of tracers busy, thanks to the successful efforts by British Columbians to social distance and reduce COVID-19 growth over the past two months.
But the public-health nurses, doctors and health inspectors who make up the contact-tracing teams remain trained and ready to go into action at a moment’s notice. In the meantime, they also do their regular jobs.
“We’re just trying to be ready whenever the next wave will come,” Hayden said.
The small army of contact tracers remains one of the province’s best lines of defence against COVID-19.
“For a long time, people were really keeping in their bubbles and staying at home for the most part,” said Mary Hein, who is a contact tracer at Vancouver Coastal Health. “Now is when we’re going to have to put those detective hats back on, because people are starting to go places.”
It’s a fascinating, but demanding, job, said Hein. The 34-year-old public health nurse has been working cases for almost five years. Before COVID-19, her small crew would track outbreaks of infectious diseases such as whooping cough, measles and tuberculosis.
The strategy remains similar for the coronavirus: People who test positive are quizzed extensively on when their symptoms started, where they’ve been, who they met, where they work, who their family is and who they live with.
Tracers go back two weeks before patients’ first symptoms to find how they might have caught COVID-19.
Then, based on the answers and more digging, contact tracers fan out to call everyone who might have come into contact with that person, from 48 hours before the first symptoms up to the present, encouraging most of those contacts to get tested and to self-isolate for two weeks.
Whenever someone else tests positive, the interview process is repeated and the web of contacts widens even further.
“It takes some skill to really elicit all of that information,” said Hein.
“People typically, despite their best efforts, are not necessarily going to remember everything without some prompting of ‘where did you eat, did you go shopping, what did you do this day?’ ”