Health officials in Western Canada are monitoring 2 new strains of COVID-19

Vancouver -

Health officials in three provinces, including British Columbia, are monitoring a pair of new mutations of the Delta variant of COVID-19. One of the mutations is already the dominant strain in one western province.

“This is not unexpected,” said Dr. Brian Conway, medical director of the Vancouver Infectious Diseases Centre.

“As long as we have community-based transmission maintained at the current levels, we will see new variants.”

The new strains, AY.25 and AY.27, are not entirely new variants, but are being called sub-lineages of the Delta variant.

“What’s remarkable about specifically AY.25 is that it appears to be the dominant Delta sub-lineage that has circulated in Saskatchewan,” said Dr. Angie Rasmussen, a virologist at the University of Saskatchewan’s Vaccine and Infectious Disease Organization.

The strains first appeared in Idaho in the summer and have since popped up in Saskatchewan, Alberta and B.C.

“There are three things we need to watch,” said Conway. “Is it more transmissible? Does it evade the vaccine? Or does it cause more severe disease? So, I think these are the three key things that we need to find out in the coming days to weeks.”

The province was not immediately able to provide data on the number of new cases in B.C. identified as one of the two new mutations.

When asked about it at a news conference Tuesday, provincial health officer Dr. Bonnie Henry stressed the importance of high vaccination rates in the fight against COVID-19 – and all its variants.

“I can't say this enough. It's the most important thing, and the prevention of transmission means that we're preventing the development of new strains of the virus, the transmission of these new variants,” Henry said.

More data should be available in the coming weeks on the transmissibility and severity of the new strains – and most importantly, if vaccines remain effective against them.