As a result, many Canadians may wonder how many more of these waves are waiting and when exactly the pandemic will end.  Experts, however, say these questions are difficult to answer.
“Unfortunately, I do not think there is a satisfactory answer to the fact that we do not really know why it depends on some variables,” said Dr.  Susy Hota, medical director for infection prevention and control at the Toronto-based University Health Network, told CTVNews.ca in a telephone interview Wednesday.  “I do not think we can see the future well enough to understand the directions we take for each of these variables.”
Dr Matthew Oughton, an infection specialist at the Jewish General Hospital and McGill University in Montreal, said it was reasonable to expect that SARS-CoV-2 would not disappear completely.  On the contrary, it is likely to continue to appear in waves, he said, especially among those who remain unvaccinated.  It is also likely to develop into a seasonal illness, most common between November and March, similar to the cold and flu season, Oughton said.
“During that season… then we would tend to see a much higher prevalence of these respiratory infections [and] “We may well see something similar to this with SARS-CoV-2,” Oughton told CTVNews.ca in a telephone interview Wednesday.  “I do not think he will leave, he is gone.”
This uncertainty surrounding the COVID-19 pandemic trajectory also extends to how many booster doses the general population will need to maintain ongoing protection against SARS-CoV-2, Oughton said.  The National Immunization Advisory Board (NACI) of Canada recently released new guidelines for fourth doses of COVID-19 vaccine, recommended for people aged 80 and over, as well as those living in long-term care or other shelters. , to receive the second helper.
Even with these latest recommendations, it remains unclear how often the elderly and other members of the general population should continue to be assisted in order to remain protected against the virus, especially when it comes to infection.  However, with studies showing that vaccine protection appears to be declining just a few months after administration, the chances of Canadians being advised to take more doses in the future are high, said Matthew Miller, an associate professor at McMaster University Michael G DeGroote Institute for Infectious Disease Research based in Hamilton.
“People should expect to continue to need boosters – the question is exactly how often, and that will be determined by how different variants continue to be and the severity of the disease they cause,” Miller told CTVNews.ca .  telephone interview on Wednesday.
It is also possible that those at higher risk for serious COVID-19 disease expect to be boosted more often than those who are not, Hota said.  This includes Canadians who are older.
“[In] “Older people know that their immune systems work differently and it is also very important to protect them because they are at a higher risk of having these serious effects from the start,” Hota said.  “So in this team, it makes sense to want to make sure you provide the best possible protection.”
NEW COVID-19 VARIATIONS MAY APPEAR
The difficulty in predicting the course of the pandemic, as well as how many more doses of COVID-19 vaccine will be needed to protect against infection, is due to the possibility of new variants occurring over time, Oughton said.  The virus itself is constantly changing and developing new mutations, he said.
“Viruses are evolving and certainly SARS-CoV-2 has shown a pretty impressive ability to evolve during the two years of the pandemic,” said Oughton, who explained that it is likely that people will continue to see new variants over time. next year.
The emergence of new variants also has an impact on how effective vaccines are at protecting against the virus and how long that protection lasts, Oughton said.  The current vaccines for COVID-19 were designed to target the original SARS-CoV-2 strain, rather than the more recent variant of concern, he said.  Since Omicron first appeared in November, recent studies have shown that while protection against vaccines against severe Omicron-induced disease remains significant, they offer less protection against symptomatic infection, especially compared to their performance against of Delta contamination.
“If you were to look at the pin protein of the variant on the market today, it’s very, very different from the pin protein [the original strain] “Two years ago,” he said.  “Thus, in a sense, vaccines become, over time, less compatible with the spike protein released as part of SARS-CoV-2.”
This reduced efficacy is reflected in some of the most recent data available on the efficacy of fourth doses of COVID-19 vaccine, Hota said.  A new study conducted in Israel and published in the New England Journal of Medicine suggests that a fourth dose of the Pfizer-BioNTech COVID-19 vaccine offers short-term protection against infection in people aged 60 and over, as the Omicron variant predominated.  However, protection against serious illness lasted for at least six weeks, the data showed, although researchers could not estimate exactly how long this protection would last because of the short study period.
The reason for this short-lived protection against symptomatic infection stems from the fact that the variant currently on the market today does not essentially match the antigen designed to target current COVID-19 vaccines, Miller said.
“What boosters do is temporarily increase the amount of antibodies in your body, and these transient increases tend to last somewhere in the area for about three months, and then start falling off again,” Miller said.  “[Booster shots] compensation for the presence of relatively poor antibodies to bind to the current Omicron variant by producing tons and tons and tons of these antibodies, but in a relatively short period of time ‘.
Pharmaceutical companies such as Pfizer Inc.  and its partner, BioNTech, as well as Moderna Inc., have begun manufacturing vaccines specifically targeting the tip protein of the Omicron BA.1 variant.  However, data based on clinical trials have not yet been published.  Therefore, Oughton said, it is difficult to predict at this time how long it will take for a new vaccine formula to emerge and be ready for widespread use.
“Until it is properly developed, studied and then produced; there may be occasional indication of subsequent amplifiers,” Oughton said.
CHANGE IN VACCINATION APPROACH
The fact that a significant portion of the world’s population remains unvaccinated also has an impact on the course of the pandemic, Oughton said.  According to data compiled by CTVNews.ca, about 35 percent of the world’s population remains unvaccinated against COVID-19, leaving large numbers of people particularly vulnerable to infection.  “As the virus spreads to more people, it presents more opportunities for mutations to develop, resulting in new variants,” Miller said.
“It is the number of infections that occur around the world that create opportunities for new variants to appear and the emergence of new variants significantly prolongs our pain,” he said.  “The sooner we address the issue of infections worldwide, the faster [the pandemic] it will be over.”
Although not perfect, current vaccines still offer some level of protection against COVID-19 infection, Oughton said.  As more people get vaccinated, the goal is to reduce the number of new infections and therefore the chances of developing new variants, he said.
“Once we have the vast majority of the population protected by three doses, I think you will see a much smaller overall impact on this population, but we are not there yet,” Oughton said.  “We still have a long way to go.”
At the beginning of the pandemic, there was hope that vaccines for COVID-19 could produce sterile immunity, Hota explained, when vaccination protects a person from becoming infected with a disease from the beginning.
“We hope these vaccines are our exit strategy, but not to discuss or think publicly about what this might look like,” he said.  “People may have thought, ‘I have to take my two doses and it’s over.’ And unfortunately, that is not the reality we are facing.”
The target of vaccines and vaccination programs for COVID-19 changed during the pandemic due to the fact that the virus itself has also changed, Miller said.  With the advent of Omicron, including subtype BA.2, it is clear that the virus’s spike protein continues to look increasingly different from what current vaccines target.  The Omicron variant has also been described to produce milder symptoms in the general population.  As a result, the focus of the vaccine program appears to have shifted more towards protection against serious diseases than from infection, Miller said.
“Because vaccines do an excellent job of reducing the risk of serious infection in people who are already relatively low-risk, it is less imperative to prevent the infection as a whole,” Miller said.  “It’s important to be realistic about expectations about what vaccines can do and to appreciate that in the end, what we want to do is not really get sick as a result …