TORONTO -- Dr. Jamie Spiegelman at first refused the COVID-19 vaccine.

As a critical care doctor at Humber River Hospital in northwest Toronto, one of the worst COVID-ravaged regions in the country, he meets the definition of a front-line worker.

But he thought there were others, from nurses to respiratory therapists, who needed it first. Besides, he says, he probably contracted the novel coronavirus in the first wave, among the 50 per cent of the population who show no symptoms.

One day last month the hospital's CEO called telling him there were leftovers from the clinic that day that would go to waste if not used.

So he relented.

Looking back over the last year, Spiegelman feels like he's needed his entire life's training to fight COVID-19.

He's treated about 150 patients with COVID-19 in the intensive care unit. About half of those have died.

"This disease has really solidified in my mind that the training that I put in, the reason why I went into medicine, has really paid off at this point because of this disease," he tells The Canadian Press over the phone.

The hospital's ICU has been full for months, to the point where they've created an additional room with six beds to treat non-COVID patients. The hospital has been steadily transferring patients out to make room for others, sending them as far afield as Kingston, Ont.

Spiegelman has seen healthy patients in their 30s and 40s succumb to the disease.

"We've had some young people die no matter what we did for them," he says. "Unfortunately, it's a disease that we don't completely understand and some patients just crash."

Yet Spiegelman remains hopeful.

Humber

"You have to look at the positives and we're going to survive it as a society," he says.

Hugging his wife and three kids after a tough day helps. And he still tries to laugh.

"Obviously, we have job security, that's another thing that we've learned from this," he says. "No one's going to kick us out."

He's learned a lot about the disease in the past year, and the damage it causes to many parts of the human body other than the lungs - mostly due to cardiac arrests and encephalitis.

Failing kidneys are an ominous sign that a patient is going to die, he says, and when a patient needs kidney dialysis, mortality skyrockets.

Spiegelman says he always tells people COVID-19 is like the movie "Avengers: Endgame," where some superheroes die and others survive.

From his own experience in the ICU as well as hospital data, about half of the people with COVID-19 tested at Humber River are fine and have no symptoms. About 35 per cent have a flu-like illness that does not require hospitalization.

Roughly 12 per cent, he says, of COVID-19 patients are hospitalized, but do not need critical care.

His job is to help the three per cent who are critically sick.

"You don't want to fall into that three per cent category," Spiegelman says.

They've seen some trends, but it's unclear if it's causal or correlational at this point. But he's noticed young, obese people fare worse with the disease and he's also seen patients with diabetes, hypertension, heart disease, kidney disease and asthma in the ICU.

Pregnant women are also at higher risk, according to the literature, but Spiegelman says they've yet to see a single pregnant woman with COVID-19 in the ICU at Humber River.

Humber River Hospital

He also believes there's a genetic component at play that somehow contributes to the severity of the illness.

There have been several cases where multiple family members come in critically ill with COVID-19 while other family members of a different ethnicity have not been that sick, he says.

"What we learned with the first and going into the second wave is all these patients are so, so sick, their lungs are so damaged from COVID-19, that they're very, very difficult to manage from an oxygen standpoint," he says.

They've found some success.

They give everyone steroids, which has reduced mortality by about 25 per cent, he says.

Pure oxygen also helps about a quarter of the patients in the ICU. The other 75 per cent in the unit go on ventilators, he says.

At that point, things can turn bad fast.

Before COVID, Spiegelman says they've never seen patients' oxygen levels plummet so quickly. In some cases, patients oxygen levels have fallen so fast that after 30 seconds they go into cardiac arrest.

They've learned to act quicker, to intubate faster, he says.

Looking ahead, he thinks COVID-19 is not going away.

"I think it's going to be kind of like the flu eventually, a yearly thing," he says. "It's just going to be part of what we have to deal with, I think, going forward."

This report by The Canadian Press was first published Jan. 24, 2020.