The report from tests on more than 30,000 people in Iceland is the most extensive work yet on the immune system’s response to the virus over time, and is good news for efforts to develop vaccines.

Coronavirus antibodies are proteins the body makes when an infection occurs; they attach to a virus and help it be eliminated.

In the trial, convalescent plasma is taken from patients who have recovered from COVID-19. That plasma, which contains antibodies to the virus, is then transferred to patients who are being hospitalized for the illness but have not yet been intubated.

The results "call for caution regarding antibody-based immunity passports," herd immunity, and perhaps vaccine durability,'' the California authors write.

The study is seeking 1,200 participants from across Canada as well as New York.

Antibodies from COVID-19 don't seem to last very long, according to a small study.

Andrew Elchuk is the first person in Saskatchewan to enter a trial examining convalescent plasma from recovered COVID-19 patients

'I think serological testing is an important part of understanding exactly how COVID-19, has been present in the country,' the prime minister said on Tuesday.

A New Brunswick man who recovered from COVID-19 was the first person in Atlantic Canada to donate convalescent plasma.