Eight ways Omicron changes what you thought you knew about COVID-19

The Star spoke with medical experts around the country about how the things you may have thought you knew about COVID-19 masking, vaccination and testing have changed.

Omicron isn’t the virus we’re used to, they say.

Will my two vaccine doses stop me from spreading COVID-19?

Not reliably, no. The experts stress that Omicron is much more vaccine-resistant, which means the two vaccine doses that had been giving you good protection against the previous Delta variant won’t do much to stop you from getting or spreading the new variant. The main takeaway, experts say, is that Omicron is just much more contagious, and can spread easily even between twice-vaccinated people.

“People with two doses can still spread the disease — it’s very different than what we saw with Delta, the science has changed,” said Dr. Naheed Dosani, a physician and health equity lead at Kensington Health in Toronto. “We should consider three doses the new definition of ‘fully vaccinated.’”

“Omicron is quite resistant to our antibodies,” added Dr. Andrew Morris, an infectious diseases specialist at Mount Sinai Hospital in Toronto. “That means we’re far more likely to become infected and transmit infection.”

The early data says two vaccinations only offer about 30 per cent protection from contracting Omicron versus an unvaccinated person. A third shot takes that number up to about 70 per cent, much closer to the previous protection two doses were giving against the Delta variant.

More infections mean more spread, which is why Morris said there is a need to “get as many boosters into people’s arms as possible.” That will reduce the risk of infection among the boosted population, which should reduce overall transmission.

Will two doses protect me from getting very sick?

The early information here is better, the experts say. More data is needed, but the risk of serious symptoms from an Omicron infection appears to be lessened in double-dosed people, according to Ilan Schwartz, an infectious diseases physician and professor at the University of Alberta.

“The severity of disease experienced by double-vaccinated people is much less than what we would be concerned about,” he said. “But there’s still a lot of information evolving. We don’t have a complete picture yet on the risk of severe disease in this particular variant in general.”

But that isn’t a reason to drop your guard, Schwartz said. A double-vaccinated person can still pass on the virus “very efficiently,” which could end up infecting someone more vulnerable, such as an immunocompromised person.

“Previously we relied on vaccinated individuals to be interrupters of chain transmission,” he said. “That’s no longer the case.”

Is Omicron causing milder illness?

“It really is too early to know,” said Morris. “We haven’t yet seen a massive explosion of hospitalizations and ICU admission. But it’s all so preliminary. Anyone who really knows and understands science still feels we need one to two more weeks to figure this out.”

But, even if Omicron is significantly milder than Delta, experts stress that the sheer amount of people expected to become infected — who will then have to quarantine away from predominately essential work, where transmission is more likely — is a serious threat.

“The greatest risk related to Omicron, in every jurisdiction where it exists, is that it’s threatening to create major imbalances in essential workforces,” said Morris. “Physicians, pharmacists, nurses, respiratory therapists — we’re going to be short of those people at various times during this wave. Regardless of the severity (of Omicron), the real threat is that we won’t have enough people.”

He added: “There are already emergency departments that are incredibly stretched and may not be able to stay open 24/7 because they don’t have the staff.”

What about all the “good news” out of South Africa?

South Africa, which saw the world’s first frightening Omicron spike, has not seen a similarly large followup wave in hospitalizations, a fact that has sparked considerable discussion about whether the variant is less severe overall. But, the experts cautioned, the same outcome is not something you should necessarily expect for Ontario.

“All the data that’s coming in from South Africa needs to be viewed in context,” Dosani said. “There are some people saying Omicron is milder because of how hospitalization has occurred in South Africa, but in South Africa, the average age is around 27, whereas in Ontario the average age is about 44.”

He explained: “Data from one region doesn’t necessarily apply to another region, especially when two regions have different populations — and we know age has been a huge factor (with COVID-19). We still have so much to learn.”

Can a rapid test tell me if I got COVID-19 at that party?

To a degree. Rapid tests are reliable when they come back positive, but a single negative result won’t tell you that you weren’t infected, the experts say.

“With a rapid test, a positive is a positive,” Dr. Eric Arts, a virologist and immunology professor at Western University, told the Star Monday. “A negative is not a definitive negative. You may still be infected, regardless of what the rapid test shows you.”

The key thing — beyond the possibility of user error — is that it can take several days after an infection before the virus is detectable in your body. This means you need to think of a single negative as a temporary result, not a clean bill of health for the days ahead.

Arts stressed that those with access to rapid tests shouldn’t stop taking them after a negative result if they are still going out around other people, particularly if they are feeling ill. “You need to continue to take rapid tests if you’re going into crowded places and high-risk situations like shopping malls,” he said. “You should repeat that rapid test the next day and the next day, especially if you have symptoms.”

Even better, if you have symptoms, stay home, regardless of what the rapid test says, and book a more accurate PCR test at an assessment centre when you can.

Will it still take about two weeks for my booster dose to kick in?

Good news here: a booster should offer protection in about half the time it took first and second doses to become effective, Ontario’s chief medical officer of health Dr. Kieran Moore said at a Tuesday press conference.

“We know with the booster dose, within five to seven days you have a significant rise in your antibody production and your memory cells are re-triggered against COVID,” he said — “you don’t have to wait the 10 to 14 like we stated (with first and second doses).”

Will my cloth mask still protect me from getting COVID?

No, said Schwartz. A better option is a well-fitting surgical mask or, better yet, an air-filtering mask like an N95 or KN95 respirator.

“It is time for people to retire cloth masks in the face of Omicron,” he said. “While cloth masks do provide some level of protection, there’s a risk of creating a false sense of security with them.”

Cloth masks were never the best face covering around, but they were passable when less contagious strains were dominant. Because Omicron is so much more likely to infect people, more protection is needed, Morris said.

“In the past, if you were in high-risk settings, there was sound reason to use an N95 mask instead,” he said. “But the importance of that has increased now. You’re just getting more benefit out of a higher quality mask.”

When will this end?

Experts predict the Omicron wave will infect more people at once than ever before — but that’s why Morris believes this wave will be short.

“We will get through this,” Morris said. “But these next few weeks are quite crucial. That’s where we’re going to see the greatest peak — in two to four weeks. This wave is not going to go on for a very, very long time. It’s growing too quickly to last for a very long time.”