Health officials in British Columbia and Saskatchewan are advising people to self isolate if they're returning from an area of Alberta where an oilsands site is suffering from a COVID-19 outbreak.

The Interior Health region in British Columbia has advised that "contacts or potential contacts" with the Kearl Lake oilsands site should self-isolate for 14 days after their last flights home.

"Many residents in the Interior Health region travel to work camps in Alberta for employment," a statement on Interior Health's website said on Saturday. "There is potential for transmission between communities and between our provinces."

Alberta's chief medical officer of health said Friday the number of Alberta cases arising from the facility north of Fort McMurray had risen to 12.

On Saturday, the Saskatchewan Health Authority said in a statement that it and the Northern Inter-Tribal Health Authority have begun a contact tracing investigation into new cases of the novel coronavirus in the province's north that are linked to cross-boundary travel.

The statement noted there have been reports of a number of COVID-19 cases at an oilsands facility north of Fort McMurray, Alta., although it didn't specify the Kearl facility or whether any of the new cases in Saskatchewan are believed to be connected to that outbreak.

But it said that all northern Saskatchewan residents should self-isolate for 14 days after returning from northern Alberta.

'Advising against all non-essential travel'

"In recognition that there are close connections between communities with regular interprovincial travel for work and other reasons, there is a potential for community transmission with continued non-essential travel between communities across the border," the SHA statement said.

"As such, regional Medical Health Officers are advising against all non-essential travel between northwest Saskatchewan and northern Alberta effective immediately and until further notice."

Oilsands operators rely on workers from across the country who fly to sites and stay there for several days or weeks at a time, and the sites continue to operate amid the pandemic as an essential service.

Imperial, which owns Kearl along with ExxonMobil Canada, said as of Thursday it had two active COVID-19 cases on site, and 10 active cases away from the site.

Simon Younger, vice-president of production at Imperial, said at the time that the company had completed contact tracing for these individuals and asked other workers to self-isolate while further testing was underway.

The company said earlier that it had bolstered cleaning and sterilization practices, and that employees are being screened at flight centres, on daily bus trips and at the site, including having their temperatures monitored.

It also said it took steps to ensure social distancing at camp and on the worksite.