Inside B.C.'s testing laboratory, technologists hunt for active cases and antibodies

Inside the testing area at the B.C. Centre for Disease Control's central laboratory in Vancouver, recirculated air carries a metallic smell. Medical lab technologists work quietly against the whir of machinery, holding samples between their fingers that could inform the province's pandemic response.

The lab is one of several sites across B.C. and Canada racing to evaluate serology tests in an effort to better understand whether people who have been infected with COVID-19 are immune to the virus once they recover.

"That is the million-dollar question," said Dr. Muhammad Morshed, a clinical microbiologist with the BCCDC.

Serology tests, or antibody tests, look for the presence of antibodies to a virus in a patient's blood. Antibodies are a sign that a patient's immune system has reacted to an infection, indicating they may have once been infected with the coronavirus and are now possibly immune.

But the tests aren't yet reliable: early studies indicate they can be flawed, easily misinterpreted with the potential for false positives.

"They are far from perfect," said Dr. Marc Romney, the division head of microbiology and virology at St. Paul's Hospital. 

On Tuesday, Health Canada said it had authorized the first COVID-19 serological test for use in the country. Part of the BCCDC's work is evaluating the effectiveness of serology tests.

The lab in Vancouver is still processing between 700 and 800 tests for active COVID-19 cases every day, down from 2,000 at the peak of B.C.'s pandemic. Provincial numbers show community outbreaks, like those within long-term care homes and poultry plants, are still a threat in B.C. even as the overall number of cases continues to drop.

"That remains a challenge as we try to relax the physical distancing. What we're trying to do is make sure there's sufficient testing to allow the decisions of how to respond to be made in real-time," said Dr. Mel Krajden, medical director of the BCCDC public health laboratory.

"We're looking to be very nimble, very responsive, look at the information that we collect on a daily basis and use that and share that with our provincial medical health officers."

The lab is also evaluating rapid blood tests for the virus, some of which can return results in 15 minutes.