Alberta and British Columbia are reporting their first cases of the Omicron COVID-19 variant that has now been detected in four Canadian provinces.

Dr. Deena Hinshaw, Alberta's chief medical health officer, said the province's case was confirmed in a traveller returning from Nigeria and the Netherlands.

"The individual tested positive while asymptomatic. I can confirm that this individual has not left quarantine since their arrival from international travel," Hinshaw said Tuesday at a news conference in Edmonton.

"We have notified the individual and their household and all necessary measures are in place to prevent transmission."

The variant of concern was first identified in South Africa after a spike in infections, but it is unclear where Omicron first emerged. Preliminary evidence suggests the new variant transmits more easily.

B.C. also announced its first Omicron case on Tuesday. Ontario reported its earliest cases on Sunday and Quebec its first case on Monday.

Dr. Bonnie Henry, B.C.'s top doctor, said the province's first case was confirmed in an individual who recently returned from Nigeria.

"They are isolating and public health is, as we do with every case, following up with them and their contacts at this time," said Henry during a COVID-19 update in Vancouver.

She said concerning mutations can spread rapidly in places where there are low vaccination rates.

#Alberta and #BC each confirm first cases of #Omicron #COVID19 variant.

"This new variant of concern reminds us that we are in a global storm and it is not equal everywhere around the world," said Henry. "Equal access to vaccination is something that's going to be important for us to get through this."

The World Health Organization, which designated Omicron as a variant of concern last week, stated it has a "large number of mutations, some of which are concerning."

Federal Health Minister Jean-Yves Duclos announced Tuesday that all air travellers entering Canada will be required to take a COVID-19 test, even if they are fully vaccinated, and to isolate until results are available.

Only people coming from the United States will be exempt.

Also Tuesday, Egypt, Malawi and Nigeria were added to Canada's border closure list, which already included bans on foreign nationals from seven southern African countries, to protect against Omicron.

Several other countries have enacted similar travel bans, despite the WHO urging countries to avoid these restrictions because they "place a heavy burden on lives and livelihoods."

Hinshaw said Alberta is ready to deal with the new variant.

"While it is important that we all continue to be vigilant in the face of COVID-19 to protect ourselves and others, I don't want Albertans to be alarmed," said Hinshaw, who added that the arrival of Omicron was anticipated based on the emergence of previous strains of COVID-19.

"We are well prepared for this eventuality and have the necessary tools in place to monitor this case and any potential spread of the variant."

The goal is to delay the spread of Omicron as more information on the variant becomes available, Hinshaw said.

All Western provinces are monitoring for the variant. Manitoba and Saskatchewan have yet to record any positive cases.

This report by The Canadian Press was first published Nov. 30, 2021.

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