An AbCellera Biologics Inc. scientist pipettes cell culture reagents in a biosafety cabinet at an AbCellera laboratory in this undated handout photo. As researchers race to develop a vaccine, the head of a Vancouver biotech company says another valuable shield against COVID-19 could work better and buy time in the interim. THE CANADIAN PRESS/HO, AbCellera Biologics Inc.

An AbCellera Biologics Inc. scientist pipettes cell culture reagents in a biosafety cabinet at an AbCellera laboratory in this undated handout photo. As researchers race to develop a vaccine, the head of a Vancouver biotech company says another valuable shield against COVID-19 could work better and buy time in the interim. THE CANADIAN PRESS/HO, AbCellera Biologics Inc.

Serological surveys to look for COVID-19 immunity in Canadian population

It’s not yet known how much immunity antibodies can offer

Canada’s top doctor says too little is known to consider using a newly approved serology test to identify individuals who could be immune to COVID-19 and allow those people to return to work or gather in public.

Instead, Theresa Tam said Wednesday that the new LIAISON test will be used more broadly to look for immunity in the Canadian population, noting questions persist about the prevalence of COVID-19 antibodies and what protections they offer.

Tam said an immunity task force had been formed to examine what protection from reinfection exists among those who have recovered from COVID-19.

“Now that you have the first test, we’re hoping to see rapid implementation of the actual population surveys, both general and those focusing on specific communities, geographies, (and) occupational groups,” said Tam, Canada’s chief public health officer.

“They’re working as fast as they can and hopefully this will be quite rapid in terms of its rollout.”

The comments came a day after Health Canada said it had authorized the first serological test to detect antibodies specific to the virus that causes COVID-19.

READ MORE: Health Canada approves serological test to detect COVID-19

The federal agency said Tuesday that at least one million Canadian blood samples will be collected and tested over the next two years to track the virus in the general population and in specific groups at greater risk of having been infected, including health-care workers and seniors.

Even if a test has been authorized, Tam said Health Canada must monitor its ability to perform in real-life applications.

“How specific are they? Can they actually detect the specific COVID-19 antibodies or not?” said Tam.

“All of that remains to be seen which just means that we need to evaluate and monitor these tests as carefully as we can.”

Unlike the current PCR diagnostic tests that tell us where COVID-19 is presently, serology tests reveal if someone has been infected in the past and has developed antibodies to the virus.

Experts say that can give us a better sense of how prevalent infection has been and how to further prevent COVID-19 spread — information that is critical as various regions of the country begin to reopen.

Nova Scotia’s chief medical officer of health noted Wednesday that serology tests could provide good information on the role asymptomatic people play in community spread.

“Nationally, there is discussion about doing a sero-survey. So you do a sample of people across the country, big enough that you can get representative numbers from each of the provinces and territories. Through that, you get a sense of how many people have been actually immune from wave one, and then we could match that up with a number of known cases we have,” said Dr. Robert Strang.

“And the difference would give us an estimation of the number of people that weren’t recognized — either they were asymptomatic or never came forward for testing.”

At the other end of the country, B.C.’s provincial health officer has already invited residents there to volunteer for a serology blood testing study.

Dr. Bonnie Henry announced the study Tuesday, along with a survey to gather information about how people have been affected by COVID-19 measures.

READ MORE: B.C. begins broad COVID-19 survey, with option for antibody testing

Patrick Saunders-Hastings, an epidemiologist and consultant with the management consulting firm Gevity Consulting Inc., said one issue with serological tests in general has been their reliability.

He agreed that the goal should be to try to determine on a broad scale who has antibodies that may protect them from the coronavirus rather than aim for individual immunity passports.

“Serological testing performance is quite variable,” said Saunders-Hastings, director of life sciences and environmental health at the firm.

“And when we do get down to the individual levels some of the sort of false positives and false negatives can be quite problematic.”

He added that serology should be used as a complement to ongoing clinical diagnostic testing, which would identify current infections.

Also unknown: the amount of antibodies needed to confer full immunity and how long immunity lasts.

Tam said it was too early to discuss the possibility of so-called immunity passports, which the World Health Organization has cautioned against.

“We really we need more information.”

Cassandra Szklarski, The Canadian Press


Like us on Facebook and follow us on Twitter.

Want to support local journalism during the pandemic? Make a donation here.

Coronavirus

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

The B.C. Legislature in Victoria, B.C. is shown on Wednesday, June 10, 2020. THE CANADIAN PRESS/Chad Hipolito
Langley to seek COVID-19 infrastructure grants

The provincially-administered funds could be used in flood prevention

Langley’s Maryalice Wood, 71, won Cranberries BC Culinary Contest in October 2020 for her cranberry walnut cheese ball recipe. (Coreen Rodger Berrisford/Special to Langley Advance Times)
Langley woman creates winning cranberry walnut cheese ball recipe

Maryalice Wood won the Cranberries BC Culinary Contest

Submit letters to the editor through our website, via email or in writing.
LETTER: Langley resident disappointed with paper’s lack of Nov. 25 coverage

Reader critical of paper for not covering International Day of Elimination of Violence Against Women

Townhouses for sale in the Willoughby neighbourhood of Langley on Dec. 2, 2020. (Matthew Claxton/Langley Advance Times)
Houses selling fast in Langley in November

Real estate markets continued to see high sales and rising prices

A Langley high school teacher was handed a one-day suspension for ‘physically intimidating’ Grade 7 student during a basketball game in February of 2016 (Black Press Media file)
Langley high school teacher gets one-day suspension for ‘physically intimidating’ Grade 7 student

Lost his temper because student was using football terms as a joke during basketball game

Provincial health officer Dr. Bonnie Henry updates B.C.’s coronavirus situation at the legislature, Nov. 30, 2020. (B.C. government)
Hockey team brought COVID-19 back from Alberta, B.C. doctor says

Dr. Bonnie Henry pleads for out-of-province travel to stop

B.C. Premier John Horgan on a conference call with religious leaders from his B.C. legislature office, Nov. 18, 2020, informing them in-person church services are off until further notice. (B.C. government)
B.C. tourism relief coming soon, Premier John Horgan says

Industry leaders to report on their urgent needs next week

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

An RCMP cruiser looks on as a military search and rescue helicopter winds down near Bridesville, B.C. Tuesday, Dec. 1. Photo courtesy of RCMP Cpl. Jesse O’Donaghey
B.C. Mountie, suspect airlifted by Canadian Armed Forces from ravine after foot chase

Military aircraft were dispatched from Comox, B.C., say RCMP

Photo by Dale Klippenstein
Suspect tries to thwart police in Abbotsford with false 911 call about men with guns

Man twice sped away from officers and then tried to throw them off his trail

An 18-year old male southern resident killer whale, J34, is stranded near Sechelt in 2016. A postmortem examination suggests he died from trauma consistent with a vessel strike. (Photo supplied by Paul Cottrell, Fisheries and Oceans Canada)
“We can do better” — humans the leading cause of orca deaths: study

B.C. research reveals multitude of human and environmental threats affecting killer whales

A logo for Netflix on a remote control is seen in Portland, Ore.,Aug. 13, 2020. Experts in taxation and media say a plan announced Monday by the government will ultimately add to the cost of digital services and goods sold by foreign companies. THE CANADIAN PRESS/AP-Jenny Kane
‘Netflix tax’ for digital media likely to raise prices for consumers, experts say

The government says Canadian companies already collect those taxes when they make digital sales

Most Read