Canadian researchers find COVID-19 antibodies last for months, likely years


Hart Jackson’s colleagues at Sinai Health in Toronto have affectionately nicknamed him ‘the human pincushion.’

For months now, Jackson has been routinely pricking his finger to provide blood samples, in hopes of helping to answer a central question in the fight against COVID-19: How long does immunity last?

And so far, the findings appear promising.

“From all indications, I think there is a good chance that it can be longer lasting,” he said.

After completing his training in Switzerland, Jackson moved home to Toronto in March 2020, just as the first wave of COVID-19 was crashing into Canada.

“At about day five (of our quarantine), my partner developed a dry cough. And then it all started, where we all had slight fevers and coughs, including our six-month-old,” he recalled.

“We got the (COVID-19 test) results back very fast, which were positive and shocked all of us.”

Following his recovery in April, Jackson heard that some of his colleagues at Sinai Health and the University of Toronto were developing an antibody test to investigate whether patients who’d previously been sick with COVID-19 were immune to re-infection.

“As soon as the trial started, I was signing up right away and hoping to get involved and provide any samples that I can,” he said. “At the time, it wasn’t known how long this (immunity) was going to last.”

But now 10 months since he became infected with COVID-19, Jackson’s antibodies remain robust. And COVID-19 researchers are growing increasingly optimistic that immunity — whether acquired through infection or vaccination — will endure for some time.

“We know several people that were infected back in February and they still have quite a bit of antibodies,” said Anne-Claude Gingras, a biochemist and senior investigator at the LTRI, who developed one of the earliest COVID-19 antibodies tests.

“The neutralizing antibodies decline a little bit, but they decline very, very slowly.”