TORONTO -- Health Canada has approved a test that can detect antibodies specific to COVID-19 in an individual’s blood, allowing Canadian labs to take a significant step forward in understanding immunity against the disease.

The test is the first of its kind to be approved in Canada and will help scientists determine whether a person was exposed to COVID-19 and, more importantly, whether or not they still have virus-fighting antibodies in their system.

The test, called the DiaSorin LIAISON, was approved Tuesday following “priority scientific review,” Health Canada said.

“Further research will also help us fully understand the relationship between positive antibody tests and protection against re-infection,” the agency said in a statement.

Health Canada has already approved 18 other diagnostic testing devices that can determine if a person is actively infected with COVID-19. The difference with the new test is that it looks for antibodies, which develop naturally in the body to fight off an infection and linger after an infection is over.

Researchers generally agree that patients who recover from COVID-19 experience some period of immunity. What remains unclear is how long that period of immunity lasts.

That lack of understanding remains a key question for researchers around the world.

The World Health Organization recently shot down the idea of “immunity passports” for individuals who test positive for COVID-19 antibodies, noting that it’s too soon to rely on antibodies as a total guarantee against re-infection.

The DiaSorin LIAISON was approved for use in the United States in April.