It is unclear why swine flu rates are higher in Inuit communities
Canada is investigating whether Inuit communities may be particularly badly hit by swine flu, health officials say.
The World Health Organization thinks there are more cases than expected among young people in the aboriginal population living in northern Canada.
Recent days have seen a spike in H1N1 flu among the Inuit and the country's isolated indigenous communities.
The swine flu virus can have more serious effects on people living in poverty, the WHO says.
Of fewer than 100 people infected in Nunavut, the vast Arctic homeland of Inuits, 10 were admitted to hospital.
In Manitoba province, 16 of the 24 people in intensive care because of swine flu are from native communities.
The BBC's Lee Carter in Toronto says there are no clear reasons why swine flu rates are higher in Canada's indigenous communities.
But poverty, substandard, overcrowded housing and underlying health problems are thought to be the most likely culprits, he says.
Canada's federal health minister, Leona Aglukkaq, who is herself Inuit, said additional personnel and supplies have been sent to the Inuit communities.
"This is a concern and we are investigating," she said. "We must resist speculation, rely on the science and report only on confirmed cases."
Four people have died from swine flu in Canada though most of the 2,978 confirmed cases have been mild.