What to know about the BA.2 COVID-19 sublineage: 'It’s coming to a nose near you as masks come off'

Mandatory mask mandates are slowly shifting in Canada, despite the continued spread of COVID-19. In Alberta, masks are no longer required, outside of public transportation, and Ontario is set to follow a similar path as of March 21.

This despite the latest incarnation of COVID-19 - BA.2 - which is not a variant like Delta and Omicron, but a sublineage of Omicron. That means it’s had a minor evolution from that variant. And research is showing it’s more contagious.

“How it initially is being described in Denmark is that this outcompetes the initial BA.1 variant that came out South Africa, so it’s spreading more quickly than that variant in Denmark,” Daniel Gregson, a Calgary-based physician who specializes in infectious diseases and medical microbiology, tells Yahoo Canada News. “Here in Alberta, we got our first cases in February and last I heard, over 25 per cent of our coronavirus islets are getting this BA.2 sublineage.”

While community testing in Alberta has largely subsided, the tests that are being conducted show that the BA.2 sublineage is growing to at least a quarter of the cases and expected to take over. Gregson says there isn’t a lot of data when it comes to reinfection of Omicron BA.1 with the BA.2 sublineage, though he adds that we aren’t six months out from the initial spread of infections.

“Usually we see immunity wane over time, so we’ll see re-infections down the road,” he says.

He adds that the severity of the BA.2 sublineage is similar to BA.1.

There isn’t substantial data on people who have no prior infection and no vaccine who contract Omicron. Gregson says that what they’re seeing in hospitals is that unvaccinated patients who’ve had no prior COVID-19 infections do worse with Omicron than people who’ve been immunized.

With the changing of mask mandates, Gregson urges people to be up to date with their two shots and a booster, to protect themselves from Omicron and to watch out for new Omicron-specific vaccines in the next six months.

Gregson says it will be hard for those who have compromised immune systems to get out of the house while this sublineage moves through the population.

“I’m expecting that there will be ongoing transmission for the next two to six months of Omicron, including this sublineage,” he says. “It will probably accelerate a little bit as soon as the masks come off, then die out as everyone becomes infected and has developed more immunity to this than previously.”

The good news is that better weather is coming. As people move outdoors and leave their windows open to get better ventilation, we reduce transmission. But for now, the best rule of thumb is to keep your distance from others in indoors spaces and keep wearing a mask.

“Unfortunately, some people masking and others not isn’t as effective as everybody masking but it’s better than nothing,” says Gregson. “If you’re immunocompromised, I’d say put on an N-95 mask. If you’re sick, stay home. If you test positive, stay home as long as possible to reduce spread.”