COVID-19 variants: 'Double mutant' is 'misleading,' B.C. physician says of B.1.617's moniker
VANCOUVER -- A COVID-19 variant dubbed a "double mutant" is spreading in India amid the country's alarming surge in case, but a B.C. doctor says its nickname is a little misleading.
CTV Morning Live spoke with family physician Dr. Melissa Lem on Monday, who said the B.1.617 variant, is not the only one with multiple mutations.
Below is part of a four-minute interview, which has been edited for length and clarity.
Keri Adams: Can you explain exactly what a "double mutant" variant is?
Dr. Melissa Lem: This term "double mutant" is a bit misleading because every variant of interest or concern, whether it's P.1, which was first found in Brazil or B.1.1.7 from the U.K., all of them have several mutations compared to the original virus, so more than two.
When viruses replicate, they typically mutate in multiple ways, so there are lots of so-called double mutants out there. But the reason people are calling this B.1.617 strain, which was first identified in India, a double mutant is because it has two famous mutations that we've already found in two other known strains: one from California and another from South Africa and Brazil.
We actually found our first B.1.617 case here in B.C. in early April and we've only identified a few dozen cases of it so far. So right now, other strains are definitely more troubling here.
Adams: How is this variant different from the original virus? Is it more risky for people's health or is it more contagious?
Lem: The latest evidence suggests it's about 20 to 30 per cent more contagious than the original, but not as contagious as the U.K. strain, which is up to 90 per cent more contagious. The World Health Organization and Canada (are) still calling it a variant of interest, not a variant of concern because so far it doesn't seem to make people sicker or spread as quickly as other variants.
I think the reason people are worried about B.1.617 right now is because … we're hearing these heartbreaking stories about India's health-care system being overwhelmed during their second wave. But we don't actually know if B.1.617 is driving the majority of their cases right now because it could be other variants.
One spot of good news is that, so far, experts still think our vaccines are very effective at preventing people from hospitalization or death.
Adams: The National Advisory Committee on Immunization recently lowered the age for AstraZeneca from 55 down to 30. Do you think B.C. will follow their guidelines and open up those vaccines to people aged 30 and older?
Lem: Just for context, Health Canada approved the vaccine for adults over 18 in February and their recommendation still stands. But in March, NACI recommended that it only be used in adults 55 and up.
The provinces were initially following NACI's guideline and did reserve it for 55 to 65-year-olds, but many people seemed to be holding out for a different vaccine. So even before NACI's guideline changed, some provinces opened it up to 40-year-olds. This age group has actually jumped at the chance to get vaccinated, so now supply of it is very low across Canada.
Even if B.C. wanted to drop the age to 30 and older, there aren't enough doses to go around right now and we probably won't be seeing another delivery until May.
Adams: A lot of people are worried about side effects. What is the latest on blood clots and AstraZeneca?
Lem: People are asking me this question every single day in my office. Data is evolving, but the latest numbers say the risk of a blood clot from the AstraZeneca vaccine is about one in 100,000. But the risk of developing a blood clot if you get COVID-19 is much higher, between one in five to one in 100.
This risk, the evidence right now says it appears to be the same no matter how old you are or if you're male or female. And patients also often ask if they have a higher risk from the vaccine if they have other risk factors like a history of blood clots or heart attack or stroke or they're on a birth-control pill, but the answer right now appears to be "no."
These clots happen randomly through a totally different mechanism where antibodies activate platelets that clump together and set off blood clots.
Within areas with high transmission like B.C., I completely believe that the best vaccine is the first one you can get.