It's been more than two years since the start of the pandemic, and yet, new data shows that nearly a quarter of Canadians are still reporting high levels of anxiety – numbers largely unchanged since 2020.

examined survey data collected by Mental Health Research Canada and funded by . The survey found that 23 per cent of Canadians are facing high anxiety while 15 per cent are experiencing high depression.

"Before the pandemic, these levels were at around four or five per cent. It's an increase of four or five times, so it's concerning," , a University of Waterloo PhD student, who has been studying the long-term mental health impacts of COVID-19, told Â鶹ӰÊÓ Channel on Saturday.

Betini says it's especially concerning that even with high levels of vaccination and few remaining COVID-19 restrictions in Canada, the rates of anxiety and depression have changed very little since the polling began in April 2020.

"It's surprising for us that these levels … haven't changed since 2020, when we started this polling. So, this is concerning going forward," he said.

Younger Canadians and individuals from marginalized groups, like the LGBTQ2S+ community, are more likely to face high levels of pandemic-induced anxiety and depression, Betini says.

"One thing that we see very commonly is that younger adults are struggling a little bit more compared to the general population. The same is true for women, especially women with young children and health-care providers, and members of the LGBTQ+ community," Betini said.

LONG COVID PATIENTS FACE GREATER MENTAL HEALTH CHALLENGES

For those who become infected with the virus and experience long-haul COVID-19 symptoms, it can be even harder to keep their mental health in check.

The Public Health Agency of Canada (PHAC) has documented reports of more than 100 potential . The most common ones, according to PHAC, include fatigue, memory problems, anxiety, depression and even post-traumatic stress disorder.

At the University of Toronto, Dr. Roger McIntyre, professor of psychiatry and pharmacology, has been leading a trial looking at better understanding how long COVID affects the brain.

"What we're trying to do is we're trying to better understand what is occurring in the brain in people who are experiencing this very debilitating, very complex syndrome post-COVID," he told Â鶹ӰÊÓ Channel on Saturday.

McIntrye says inflammation due to an immune response to exposure of the virus may be one culprit when it comes to pinpointing why some people are having long COVID symptoms. He says his trial is also testing a treatment that affects the immune systems, which can also benefit

"aspects of the brain fog and the fatigue that are so ubiquitous in this condition."

It's unclear how many people are affected by long COVID symptoms. Early data from the World Health Organization showed that 10 to 20 per cent of those infected with the virus could go on to become COVID long-haulers, but Tam said on Friday that more up-to-date research indicates it could actually be as high as 50 per cent.

But in the absence of treatment options, McIntyre says for now, prevention via vaccination is the most important tool to prevent long COVID symptoms.

"The best treatment always is prevention. And we have a signal in our literature that's telling us if you get vaccinated … the probability of you having long COVID may be less. The severity of long COVID may be less," he said. "As we think about protecting ourselves, the vaccine is clearly an important tool for us."

With files from The Canadian Press