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       Tam says the vast majority of new COVID-19 cases in Canada are among unvaccinated parts of the population.

       Justin Tang/The Canadian Press

       Canada’s chief public health officer says the country is now in the midst of a fourth wave of the COVID-19 pandemic.

       Dr. Theresa Tam’s assessment follows a troubling surge in new cases over the past two weeks that is being driven by the Delta variant.

       It also comes as Prime Minister Justin Trudeau is expected to ask Gov.-Gen. Mary Simon to dissolve Parliament as soon as this weekend.

       That would trigger an election campaign, sending federal politicians onto the hustings amid the possibility of new lockdowns.

       Tam declined to say whether she would advise against a federal election during a new wave of COVID-19 cases.

       But she did say that she expects anyone who is campaigning to follow local public health rules.

       Tam says the vast majority of new COVID-19 cases in Canada are among unvaccinated parts of the population.

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