TORONTO -- When Megan Desjardins attempts to garden these days, she has to take multiple breaks to catch her breath. A recent walk on the beach with her family left her exhausted and in need of a long nap.

In early June, her chest was sore, her nose was numb, her arms were weak, and she had to lean on a chair just to hold the telephone up to her ear.

鈥淵ou wake up every day thinking 鈥極K, what pain is it going to be today? What am I going to experience today?鈥欌 she shared with CTVNews.ca during a call from her home in Comox, B.C.

Desjardins believes she contracted COVID-19 during a trip to Costa Rica and Panama in January and February. She said she experienced the first signs of illness -- chest pain, raw itchy eyes, and a headache 鈥 on March 17.

That was 85 days before she spoke to CTVNews.ca for this story.

鈥淚鈥檓 a healthy person normally,鈥 she said. 鈥淚鈥檓 not overweight, I don鈥檛 smoke, I don鈥檛 drink, I don鈥檛 have recurring serious chest or health issues鈥 this isn鈥檛 just a little cold that lasts for a couple weeks. It鈥檚 been three months.鈥

Desjardins, and thousands of other self-described 鈥渓ong-haulers,鈥 believe the chronic symptoms they have experienced for weeks and even months are the result of COVID-19 infection, even though many of them have never tested positive for the disease.

That鈥檚 because most of them were unable to get tested when they first started showing symptoms due to the availability of tests in their area, or they received a negative test result when they were finally able to get one weeks later.

This doesn鈥檛 mean, however, they never had the disease and doctors and researchers say there are a number of possible explanations as to why they鈥檙e experiencing these symptoms and why they tested negative for COVID-19.

Ken Borg, who never bothered to get tested when they were finally made available in his area, said he lived a healthy lifestyle before he fell ill from what he believes to be COVID-19. He played hockey twice a week and went snowshoeing three times a week.

Now, Borg is easily tired out by a round of golf with his friends.

鈥淚t鈥檚 been a long recovery,鈥 he said during a telephone interview from his home in Ottawa in early June. 鈥淚鈥檝e never had as many naps as I鈥檝e had over the last three months.鈥

He believes he was infected with coronavirus at a house party in early March, which included several attendees who had recently returned from abroad.

On March 11, the 58-year-old retiree experienced his first symptom -- a congested throat.

Since then, Borg has experienced waves of fatigue, chest pain, heart palpitations, high-blood pressure, as well as red, painful lesions on his toes, or 鈥淐OVID toes鈥 as the condition has been sometimes called.

And while the heart palpitations appeared to have stopped last week, Borg said he still experiences fatigue and his breathing isn鈥檛 completely back to normal.

He was on day 92 of his recovery when he shared his story with CTVNews.ca.

It鈥檚 been a long journey for Tracey Thompson, too. She was on day 88 of her recovery when she spoke with CTVNews.ca. She started showing symptoms on March 15.

While she initially didn鈥檛 have any of the usual respiratory symptoms associated with COVID-19, such as coughing or trouble breathing, she did experience a fever, gastrointestinal issues, and fatigue.

鈥淚 was very concerned about it,鈥 she recalled during a telephone interview from her home in Toronto in early June. 鈥淚 didn鈥檛 know what was going on and I was definitely not OK. It wasn鈥檛 anything I had experienced before.鈥

As the weeks dragged on, Thompson said new symptoms would appear, disappear, and then reappear with no warning. She had days where she felt like she was in a fog, she had rolling fevers, sore throats, chest pain, and lost her sense of smell and taste.

Because she works in a restaurant in Toronto that鈥檚 currently closed because of the pandemic, Thompson has been able to ride the wave of new symptoms in isolation at home.

鈥淚鈥檓 in limbo,鈥 she said. 鈥淓very week I keep thinking, 鈥極K it鈥檚 going to be over鈥 and every week it鈥檚 not and I can鈥檛 get any answers.鈥

Thompson has tried to find those answers by calling telehealth and visiting her local testing unit, but she hasn鈥檛 been given a clear explanation as to what is happening to her. She believes her symptoms are from a COVID-19 infection.

That鈥檚 why she resorted to a popular , which aims to connect COVID-19 survivors and share information on the disease.

And it appears Thompson isn鈥檛 the only one in search of answers.

The Survivor Corps group has more than 54,000 members, many of whom describe themselves as 鈥渓ong-haulers鈥 who have suffered from symptoms for weeks or even months.

Another popular , created by a New York City-based queer, feminist collective called Body Politic, has had more than 4,000 members join their discussion channels on the messaging platform Slack.

One of their busiest Slack channels is dedicated to people who have had symptoms for more than 30 days. It鈥檚 a place where members can 鈥渇eel connected and supported through infection, symptoms, and recovery,鈥 according to the founders.

Body Politic recently of 640 of their long-haulers, which is not peer-reviewed or representative of the entire group, and found that symptoms among respondents were not limited to cough, fever, and shortness breath.  

In fact, some of the more widely reported symptoms included fatigue, body aches, headache, brain fog, gastrointestinal issues, dizziness, chills, sweats, and trouble sleeping.

Interestingly, the survey found the majority of respondents were between the ages of 30 and 49 (62 per cent).

The survey also noted that nearly half of respondents (48 per cent) were denied testing or didn鈥檛 receive a test for another reason. Of the quarter who tested negative for COVID-19, they were, on average, tested six days later into their illness than those who tested positive.

TESTING NEGATIVE 

While many respondents in the survey and commenters in the support groups tested negative for COVID-19, if they were tested at all, that doesn鈥檛 necessarily mean they didn鈥檛 have the disease.

In March, when Desjardins, Borg, Thompson, and many others in these groups started showing symptoms, nasal swabs used for testing for COVID-19 were in high demand and in most areas, reserved for those with compromised immune systems, health-care workers, people in close contact with infected individuals, and travellers recently returned from international locations.

During this time, people with mild symptoms who did not require hospitalization and who were not at a higher risk of a serious outcome were advised to isolate themselves at home and monitor their symptoms.

It wasn鈥檛 until the end of April to mid-May, when testing became more widely available to residents in Canada, that people like Desjardins and Thompson were finally able to get tested.

Like many others in the support groups, they both tested negative.

Thompson said a health-care worker at Mount Sinai Hospital鈥檚 assessment centre in Toronto emailed her to tell her that even though she received a negative result, she most likely had COVID-19 at some point and she鈥檚 鈥渘ot crazy.鈥

鈥淪he鈥檚 like 鈥極h yeah, you definitely had it,鈥欌 Thompson recalled.

Dr. Iris Gorfinkel, a family physician and medical researcher in Toronto, has been particularly interested in the topic of long-term symptoms.

That鈥檚 because several of her patients and her sister, a family doctor based in Chicago, are currently going through it.

Gorfinkel said there are a number of possible explanations as to why long-haulers receive negative test results when they are tested. She said there鈥檚 the possibility that the test isn鈥檛 picking up the virus because it鈥檚 only taking the sample from the area inside the nose.

鈥淲hen we do a swab, we鈥檙e limited to the one area that the swab has touched,鈥 she explained during a telephone interview in early June. 鈥淚f I swab the nasal pharynx, I鈥檓 testing the one area that that鈥檚 touched... There could be tons of virus that鈥檚 like two inches below that.鈥

Initially, COVID-19 was considered a respiratory illness, but Gorfinkel said researchers now know coronavirus, or SARS-CoV-2, can infect different organs or regions in the body, such as gastrointestinal areas and the neurological space. She said the virus has been found in stool samples, in blood, and even in cerebral spinal fluid.

Another potential explanation for the negative test results may be that the virus has already damaged these areas in the body and has since cleared by the time the person is tested, Gorfinkel said.

For example, she said the loss of smell and taste is a result of damage to the olfactory nerve.

In addition to Gorfinkel鈥檚 explanations above, there have been concerns about the reliability of nasal swabs after several documented cases of false positive and false negative test results.

A number of factors can affect the outcome of the tests, including the quality of the sample, the type of tools used in the test, and what stage of infection the patient was in when they received the test.

, a false negative result became more likely if the patient was tested a week after their first symptoms emerged.

Timing was the reason Borg said he never bothered to get tested. He said by the time he was eligible for a test, he figured it was too late and the result would just come back negative. Instead, he said he鈥檚 waiting for a serology or antibody test to become available in Canada, which might indicate whether he had COVID-19 due to the presence of antibodies to the virus in his blood.

Even without the confirmation of a positive test result, Desjardins, Borg, and Thompson, and countless others in the support groups are convinced they contracted COVID-19 and that is what鈥檚 behind their persistent and sometimes debilitating symptoms.

鈥淧eople in my situation are pretty frustrated because you kind of feel like you fall through the cracks of the health-care system,鈥 Desjardins said. 鈥淚鈥檓 pretty positive that this is what I have.鈥

鈥楳EDICAL MYSTERY鈥

Because research on COVID-19 is still in its infancy, there could be more than one explanation as to why some patients experience chronic symptoms and the majority don鈥檛.

Amir Attaran, a professor of law and epidemiology at the University of Ottawa, said he was reluctant to speculate on why this happens to certain individuals, but said he thinks it鈥檚 related to the immune system.

鈥淭here is undoubtedly in some COVID patients an abnormal reaction of the immune system that can contribute to the pathology that they experience,鈥 he said during a telephone interview in early June.

While Attaran didn鈥檛 feel comfortable going into specifics, Rob Kozak, a clinical microbiologist at Sunnybrook Hospital in Toronto who helped isolate the SARS-CoV-2 virus in March, said there could be several reasons for an abnormal immune response.

Kozak said there is the possibility that 鈥渕olecular mimicry鈥 is occurring, where proteins in the virus might resemble proteins in the person and the immune system has trouble distinguishing between them.

鈥淭he immune system has been all geared up fighting the virus and it recognizes proteins on the virus and goes out and attacks it. But then once all the virus is cleared, it sees proteins in the host that look not identical, but similar, and it thinks the fight is still going on,鈥 he explained during a telephone interview from Toronto in early June.

Another explanation, according to Kozak, is that even after the infection clears, viral RNA or genetic material from the virus remains in the body and the immune system detects it and launches another attack.

鈥淭he immune system doesn鈥檛 realize that the fight is over,鈥 he said. 鈥淚t sees these parts of virus and it continues to produce inflammation, produce cytokines [small proteins that regulate inflammatory responses], produces inflammatory response.鈥

Kozak said the long-lasting symptoms in certain individuals could be the result of either explanation or a combination of both. However, he said because there are so few cases and limited data, it鈥檚 difficult to know what is really responsible for the various conditions.

Gorfinkel, too, agreed there is the possibility of an overzealous immune response that is unique in certain patients.

鈥淭here are lots of individuals who will get it, who are older, who are at high risk, they've got every risk factor, and yet they get over it,鈥 she said. 鈥淚t鈥檚 not just a question of being older and having chronic conditions, it鈥檚 much more complicated than that.鈥

While Gorfinkel said the immune system may play a role in what is occurring in long-haulers, she also said these patients could have other health problems or conditions that are causing these symptoms, but they鈥檙e being overlooked because of all of the attention on COVID-19.

鈥淪o when patients have problems, and COVID is a huge footprint [top of mind] in the brain does that mean that it's always COVID? No. We have to still think could it be other diagnoses?鈥

Because the topic of the pandemic has become unavoidable, Gorfinkel said that some individuals may be experiencing physical symptoms stemming from psychological issues.

鈥淧revious influenza epidemics have been associated with an increase in anxiety, insomnia, fatigue and depression,鈥 she said.

What鈥檚 more, Gorfinkel said people who did contract COVID-19 may have lingering physical symptoms that are the result of the psychological trauma they have experienced during the crisis.

Finally, Attaran said doctors and researchers still need time to study the viral pathogenesis 鈥 how the virus causes pathology and illness 鈥 before they can fully understand the long-term symptoms in some individuals.

鈥淭his is just going to be a great medical mystery for years to come,鈥 he said. 鈥淲e鈥檒l figure it out.鈥

And while these chronic symptoms may only affect a minority of COVID-19 patients, this uncertainty combined with prolonged illness can be life-altering for those experiencing it.

鈥淚 think the majority of people don鈥檛 get it,鈥 Thompson said. 鈥淚t鈥檚 not like anybody鈥檚 visiting me in the hospital or anything like that, but鈥 I don鈥檛 think that people understand how debilitating it is.鈥

Gorfinkel, however, said the body is capable of eventually recognizing a viral infection and developing an adequate response to it over time.

鈥淲e know that the body鈥檚 immune system is capable of incredible feats and that is true even long after a disease is established,鈥 she said. 鈥淪o just because they鈥檝e had it for months, that does not mean it鈥檚 going to go on forever after that.鈥

With files from The Canadian Press

Edited by CTVNews.ca producers Kieron Lang and Sonja Puzic.