Long COVID is 'not rare' and can develop after mild illness, says Montreal specialist

The Quebec government is setting up 15 clinics across the province to treat people with long COVID and Lyme disease. The first one to open in Montreal is located at the Jewish General Hospital.

CTV News Montreal's chief anchor Mutsumi Takahashi spoke with MUHC infectious disease specialist Dr. Donald Vinh about long COVID, the clinics and ongoing research on post-COVID conditions.

This interview has been edited for clarity and concision.

MT - What exactly are we talking about when we say long COVID?

DV - Well, the World Health Organization defines long COVID as the illnesses that occur in people with a history of probable or confirmed SARS CoV-2 infection, with symptoms and effects developing usually within three months from the onset of COVID-19 and lasting at least two months - and it's not due to another medical condition.

So for this reason, long COVID is also called post-acute sequelae COVID, or what we call in Canada, post-COVID conditions (PCC). There are four key issues with PCC that people should know about.

First, it's not rare. If you look at data from around the world, we estimate five to 35 per cent of people infected with COVID will have PCC.

Second, you don't need to have had life-threatening COVID or hospitalization from COVID to develop PCC. In some studies, a third of people only had mild COVID before going on to develop PCC.

Thirdly, the manifestations can be quite debilitating. Some of them are actually due to progressive organ damage. And lastly, the diagnosis of PCC can be quite challenging. And that's why the federal government mobilized the PCC Task Force which I'm proud to sit on and the provincial government is mobilizing PCC clinics. So this will allow us to better understand the disease. But I have to be honest with you, as we allow more and more virus to circulate, this problem can become worse and worse.

MT - So what are some of the conditions that fall under this category?

DV - Well, it's become very clear to me that PCC is not one condition. PCC is an umbrella term that refers to a group of disorders that can develop after SARS CoV-2 infection. Some of the disorders can affect the brain and nervous system so which can give people what we call cognitive deficits. It kind of sounds like dementia a little bit. It's commonly referred to as brain fog. But you can develop all other kinds of neurological problems like memory problems, movement disorders, strokes, and seizures. Some of the disorders affect the lungs so people can develop blood clots or scarring of the lungs which can compromise breathing. Some disorders affect the heart and cause arrhythmias, which means that your heart beats funny or that there's inflammation that's damaging your heart, and that leads to heart failure. And some people have problems with their immune systems. The issue, unfortunately, is that we're only at the embryonic stages of understanding the breadth of complications that fall under PCC.

MT - Now, these clinics that are looking into long COVID are also designed to treat people with Lyme disease as well. What's the connection here?

DV - I need to define what Lyme disease is. Lyme disease is caused by a special bacteria called Borrelia. It's prevalent in the Northeast and Midwest areas of North America. It's transmitted by ticks during the summer season. And it causes really three distinct stages of diseases. Each of those stages has different manifestations with the second and third stages affecting things like your brain, your nerves, your heart and your joints. So clearly, there are some similarities between COVID and Lyme disease. But they're really two different diseases.

The problem is that with both, you can have your infection earlier, but then you can have late manifestations that can affect various organs and this can occur well after the infection occurred. So when someone presents with some of these textbook, late symptoms, along with a validated test result, that documents they had the preceding infection, the diagnosis is straightforward. The problem is that there are many people who have similar types of symptoms, but without any test confirming that they've had a previous infection, and that's when the diagnosis becomes very difficult. It's in the same category as another thing that we call chronic fatigue syndrome or myalgic encephalomyelitis. The problem is that because all these conditions are very hard to diagnose, people are more at risk of being dismissed by healthcare professionals, so, therefore, there are ongoing symptoms, and they continue to suffer. Hopefully, the dedicated clinics will improve their care, and very quickly.

MT - Don, you say you are on the task force looking into this. What are some of your main questions?

DV - Well, the thing about long COVID is that it's not the only infection where you can get an acute infection, where you have an acute illness and then some long-term complications. There's a whole range of other infections that have been well-known for decades to cause that. For the acute process, while our job as physicians is to find the germ, give medications to kill it and get that person back to health, the problem is in those people who aren't back to health, why don't they go back to health? What are the causes of all these complications? Is it immunologic? Is it genetic? That's what researchers are trying to figure out now.