This long-haul COVID-19 patient is unlike most. She's a respiratory scientist studying the condition

A McMaster University researcher with lasting coronavirus symptoms such as brain fog, dizziness and a distorted sense of smell that would lead to headaches is putting her expertise as a respiratory scientist to use to learn more about long-haul COVID-19. 

McMaster researcher Manali Mukherjee wants to see why some COVID patients develop autoimmune-like symptoms

Manali Mukherjee has launched a research project out of St. Joseph’s Healthcare Hamilton that brings together experts from several fields to follow 120 long COVID patients over the course of a year. (Supplied)

Months after contracting COVID-19, Manali Mukherjee was still experiencing symptoms such as brain fog, dizziness and a distorted sense of smell that would lead to headaches.

It's now been a year since she got sick, and some of the symptoms still come and go.

But unlike most with so-called long-haul COVID-19 — experiencing a constellation of symptoms that can also include shortness of breath, chronic fatigue, depression and hair loss — Mukherjee is a respiratory scientist who's using her expertise to learn more about the condition. 

Mukherjee has launched a research project from St. Joseph's Healthcare Hamilton that brings together experts from several fields — including clinical researcher Kostas Tselios, pulmonary imaging expert Sarah Svenningsen, a panel of medical expert advisers and a team of research assistants — to follow 120 long-haulers over a year.

Mukherjee said they hope to answer questions including:

  • Whether the severity of long-haul COVID-19 can be related to rheumatological complications triggered by the illness.
  • Why some patients develop autoimmune-like conditions after contracting the virus, and who is most likely to develop them.
  • Whether vaccination plays a role in the severity of long-haul COVID-19 symptoms.
  • Whether most people see a change in their symptoms over time.

"We'll be looking at blood and lung-function tests and patient-reported outcomes, in every way possible," she said.

Her team will use a variety of clinical diagnostics tests, molecular research tools and patient-related health outcome questionnaires to thoroughly detail each patient's physical condition at three months, six months, nine months and a year after their acute illness.

Omicron patients not yet included 

Mukherjee's team is one of many around the world trying to nail down the specifics of long-haul COVID-19, with the goal of helping find treatments.

For the Hamilton team's work, so far 25 participants have been recruited and they're looking for more.

People who have had a COVID-19 case confirmed by a PCR test or antibody serology testing that shows an infection, and who also have lingering symptoms can reach out to her through her contact information posted on the website of McMaster University, where she is an assistant professor of medicine in the respirology division.

"The biggest thing our long-hauler community can do is sincerely take part in our studies and in research to really help the physicians and scientists to unravel it," she said.

The researcher said there are known post-viral syndromes for other viruses, so the existence of long-haul COVID-19 is not a surprise.

That said, she added, "it's become such a monster in our heads for the sheer numbers that you can see it will affect."

That requirement for a PCR test means her study won't include people who have contracted the COVID-19 Omicron variant, as such tests are no longer widely available. It also won't include those who got sick in the early days of the pandemic before PCR testing became commonplace.

While acknowledging that as a hurdle, she's looking for ways to "streamline" the study design so such subjects can be included down the road.

Various studies released in the past year put the rate of long-haul COVID-19 at between 20 and 50 per cent of those how contract the virus.

Mukherjee said even if 10 per cent suffer long-term symptoms, that will add up to a large enough number to put serious demand on the health-care system. Ten per cent of Canada's current population is nearly four million people. 

Her hope is that by getting more insight into how long-haul COVID-19 behaves over time, it will make treatment pathways for different types of patients more clear.

"Objective measures are so important to have," she said, noting few studies have looked at the same patient over a duration of time. 

Genetic test to predict severe COVID on the horizon

Tselios, the study's clinical researcher, said that after seeing numerous patients with post-acute COVID-19 syndrome (PACS), the medical name for long-haul COVID-19, he is starting to see some trends. 

He said patients typically report fatigue, shortness of breath, difficulty sleeping, loss of taste and smell, headaches, brain fog and widespread pain in various parts of their bodies. Children are more likely to face abdominal aches and gastrointestinal problems, the researcher said.

Tselios said PACS research around the world is starting to show people with more severe illness tend to have more severe long-COVID symptoms. That means people with conditions that predispose them to severe illness — such as obesity, conditions affecting the lungs, heart and kidneys, and diabetes — "increase the possibility for more severe illness and the possibility of long COVID."

For these reasons, he believes, most of the long-haul COVID-19 population going forward will come from those who aren't vaccinated.

The good news is science is getting close to being able to predict severe COVID-19 with a genetic test, he said. 

"There are some very good studies that show if you have [a specific] gene, you will most likely end up in the hospital," he said. "Now they're trying to show genetically if there's anything that could predispose you to long COVID."

'I'm impatient, I want to know the answer now'

Part of Mukherjee's wider work includes collaborating with members of the Canadian Respiratory Research Network on a national study on PACS. 

The study, led by Andrea Gershon of Sunnybrook Health Sciences Centre in Toronto, will follow 650 people across Canada who have had COVID-19, in an effort to determine the prevalence of long COVID across various demographics, to determine risk factors for long COVID and to characterize the physiologic changes that come with the syndrome.

Dr. Andrea Gershon, of Sunnybrook Health Sciences Centre in Toronto, will follow 650 people across Canada who have had COVID-19 to determine the prevalence of long COVID, to determine risk factors and to characterize the physiologic changes that come with the syndrome. (Supplied)

"The immediate outcome we're hoping to have is just a guideline to give physicians and patients, [explaining] what to do," Gershon told CBC Hamilton. "What kind of screening should you do after COVID? What should you do when people show up with symptoms? We want people to get the health care they need, but we also don't want to bankrupt the health-care system or overtest people."

Gershon sympathizes with PACS patients who want answers sooner. 

"I'm impatient, I want to know the answer now," she said, but "it takes a long time to understand a disease. Especially one that goes months and months, or years and years."


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