A Canadian research scientist is using frozen blood samples, taken two decades ago from thousands of people across the North, in hopes of revealing new clues about hepatitis B.

The 14,000 samples, collected about 20 years ago from people in communities across the Northwest Territories and modern-day Nunavut, have since been kept frozen in an Alberta laboratory.

Now, as part of an International Polar Year research project, scientists are putting the samples through current research technology to learn more about various strains of the blood-borne virus.

"This is a tremendous resource, really, for Canada and particularly for the Arctic region, because I can say that there really is no other sample set like this in the world," said Dr. Carla Osiowy, a research scientist with the Public Health Agency of Canada's National Microbiology Lab in Winnipeg.

"It's providing us with a snapshot in time of what has occurred with hepatitis B virus."

Osiowy said she has found a new sub-genotype — a strain within a strain — of hepatitis B among people in Nunavut, related to a strain found in Japan. She said this particular strain produces a milder form of the disease in which those infected carry the virus but are otherwise healthy.

"Therefore, we're very interested in knowing whether this particular new sub-genotype is highly prevalent in the North," Osiowy said.

"It may allow us to possibly predict what we may expect as a future clinical outcome in this particular population, based on what we know from a very small sample subset."

During the mid-1980s, Dr. Bryce Larke — now the Yukon's chief medical health officer — and nurse Glory Froese travelled to arenas, bingo halls, schools and even a liquor store in 51 communities, taking blood samples from Inuit, aboriginal, Metis and non-aboriginal individuals.

Their work was part of an effort to pinpoint which communities had higher infection rates of hepatitis B to determine which communities most needed an expensive new vaccine to fight the virus. They found Inuit and aboriginal peoples had higher infection rates than other Canadians.

The original study searched for an antibody, or viral protein, in the blood samples. Osiowy said she can now use modern technology on the 20-year-old samples to find out more about what's in the blood.

"Now we have the means to do a molecular detection. With these techniques, I'm able to do a more thorough analysis of the virus that was found in those individuals that were infected."