Ontario’s COVID signs point to the start of a summer surge

Signs are emerging that point to the start of a summer surge of COVID-19 in Ontario, warns the head of the province’s science advisory table.

Dr. Fahad Razak, Scientific Director of the Science Table, points to an increase in COVID sewage signal, an increase in test positivity, and an increase in public health units experiencing exponential growth in cases.

There has been a gradual increase in sewage signal across the province since the beginning of June, along with test positivity that has increased over the past three to four weeks. Then there’s the fact, he says, that about 40% of public health units now have a reproduction number greater than one — all of which amounts to evidence that the province has entered another wave.

« Putting it all together, I think we’re seeing the start of a wave, » Razak said. « But it doesn’t seem to have the intensity in terms of amplitude or pace of what we saw with the start of the Omicron wave. How fast it will increase and what the peak will be is unclear.

« From everything we’re seeing, both in Ontario and globally, this is likely a less severe wave than we’ve seen in the past, with less direct pressure on the system. health.

Razak’s red flag comes as the National Advisory Committee on Immunization recommended this week that additional boosters be given to a larger portion of the population in the fall. Other regions are also seeing an increase in hospitalizations driven by Omicron subvariants, including Quebec, which has recently seen an increase in community transmission and cases among healthcare workers.

Meanwhile, the World Health Organization reports that infections are rising in 110 countries due to the BA.4 and BA.5 subvariants, leading to an overall 20% increase in cases worldwide.

Several infectious disease experts say a fourth dose should be offered to all residents now before a possible fall surge, while others say only those deemed to be at higher risk should receive a second booster.

“If you are someone who is at higher risk or is in a situation where you are exposed a lot because you are on TTC twice a day, at work and outside or something like that, that would be very reasonable to go get that fourth shot now, » Razak said. « On the other hand, if you’re otherwise low risk and have very little day-to-day exposure, it’s reasonable to wait to get this booster dose until you are closer to falling or there is more of a concrete increase occurring.”

At a press conference on Thursday, Dr. Theresa Tam, Canada’s chief public health officer, said up-to-date vaccinations are the « foundation of our protection » and that those who have received two doses and a booster had five times higher hospitalization rates. lower than that of unvaccinated people during the Omicron wave in April and May.

She also reiterated NACI’s recommendations that people at risk of severe illness now get a fourth vaccine, as boosters « increase protection by activating your immune response to restore protection that may have diminished over time. »

Dr Gerald Evans, chair of the division of infectious diseases at Queen’s University, said it was uncertain whether the fourth doses would be effective enough against BA.4 and BA.5 for the general population. . These subvariants show an alteration within their genomes, which makes it more difficult for antibodies to bind to spike proteins, making these variants more likely to have immune evasion properties, he explained. .

Pfizer and Moderna are developing vaccines that will specifically target Omicron, known as bivalent vaccines, which will likely be available in the fall. Both companies say they have tested their vaccines and that they appear to be very effective against Omicron, and plan to submit their data to governments in the coming months.

“I totally agree that we should be rolling out boosters in the fall,” Evans said. He predicts that one wave will occur in late fall or early winter, and another will follow in late winter or early spring, because that is how the COVID- 19 behaved before, like other diseases in the coronavirus category, he said.

NACI also announced in a statement on Wednesday that anyone between the ages of 12 and 65 could be offered another dose in the fall, regardless of the number of previous doses, but this recommendation is « discretionary » and not binding. not classified as a strong recommendation.

These groups include all residents over the age of 65; people 12 years and older who have underlying medical conditions; Aboriginal adults; racialized and marginalized communities who have been hardest hit by the virus throughout the pandemic; migrant workers; residents of shelters, correctional facilities and group homes.

Recommendations will be provided on the type of COVID-19 booster dose that should be offered as evidence emerges on bivalent vaccines.

NACI said in its press release that “COVID-19 cases, including hospitalizations and associated deaths, are currently declining in Canada. However, the likelihood, timing and severity of a future wave of COVID-19 are uncertain.

Colin Furness, an infection control epidemiologist at the University of Toronto, said he’s worried the growing signals Ontario is experiencing could mean we’re approaching endemicity.

“I believe when we took off the masks on the TTC, we started harmonizing different sewage signals in the GTA. In other words, mixing people on the TTC isn’t going to lower one sewage treatment plant’s signal, it’s going to raise the others to match,” he said.

“If you think about it logically, that kind of synchronization is a pathway to endemicity. Not a wave that comes and then subsides, but a new normal where the line is flat but at a very high level.

He added that the elevations in sewage signals, as well as cases at public health units, reflect the dropping of mask mandates earlier this month.

“But it’s not just that. It’s the mindset that goes with it. We’re seeing more and more people who should know better engage in crazy, risky behaviors,” Furness said. « If I can be on the TTC and I don’t need a mask, then I can go out to dinner because it’s obviously less dangerous and if it is, I can definitely go see a movie.

« This causes a self-destructive logic to take hold. »

TO SHARE: