OTTAWA – Mask more. Wash more. Stay home. Keep your distance. Always.

That message hammered into everyone, every day, by every provincial and federal official is a tough sell in the second wave of the .

COVID-fatigue is real.

Now one of Canada’s top public health doctors admits it poses a genuine challenge to officials who are trying to understand how the virus still has the upper hand, and how to engage people to combat it.

Deputy chief public health officer Dr. Howard Njoo mused aloud this week that scientific modellers did not accurately foresee how human behaviour – especially COVID-fatigue — would factor into the rising second wave and be such a tough thing to predict.

Epidemic modelling in the spring predicted a best-case scenario, in which strong infection control measures were in place, would see Canada experience 11,000 deaths over the entire course of the pandemic.

But just nine months after the World Health Organization declared the pandemic, that number has already been overtaken, with one global tracker reporting Canadian COVID-19 deaths at 11,165 as of Wednesday.

Dr. Theresa Tam, Canada’s chief public health officer, attributed it to the high number of deaths in long-term care homes.

In the spring, Njoo said, modellers focused on technical variables like attack rate and projections, “and so on and so forth.”

But one thing “we didn’t take into account — and it’s something we’re learning about — is the human behavioural aspect and the fact we’re all suffering COVID fatigue.”

Njoo said people “bought into” the need to wear a face mask and physical distancing in the spring, and by now, they know “there’s a higher risk in terms of closed settings of being exposed.”

But the second wave has been tough.

“How do we get people to understand and appreciate that the situation now is just as severe if not worse compared to what we endured in the spring? That to me is a big learning in terms of the social and behavioural aspect of this.”

Raywat Deonandan, an epidemiologist and associate professor at the University of Ottawa, agrees that there were challenges that made it difficult to forecast just how tough this wave would be.

First, he said, “the degree of anti authoritarianism was not expected, and therefore not included in models” as non-compliance.

Second, “the degree of misinformation and disinformation was not expected, and that directs human behaviour.”

Third, the nature of this disease itself was not expected. Now it spreads by explosive super-spreading events, rather than seeping out uniformly like the flu.”

And finally, Deonandan wrote in response to the Star, “the compartmental nature of human interaction is not included in many models, how most of us only interact with a set number of people in our given lives.”

In an interview Wednesday, Njoo said the coronavirus has challenged both public health modelling and messaging in many ways.

First, he said Canada based its pandemic planning on an influenza pandemic and how a respiratory infectious disease typically behaves. But the novel coronavirus had unique characteristics – for example asymptomatic transmission, and airborne transmission by smaller, not just large, droplets – which were not immediately known.

He pushed back at critics who say Canadians were confused because public health authorities kept changing their advice, saying public health messages on masking and physical distancing had to — and did — evolve along with the science.

“But part of my learning was that we never anticipated that, let’s say even with the wearing of masks and so on, we never anticipated we’d all be doing it for so long.”

That’s where fatigue comes in.

And Njoo doesn’t think its depth as a cultural and social factor was foreseeable.

“This is an unprecedented pandemic,” he said. “Even with H1N1, I don’t think we got into the depth or length of having to deal with it for this period of time.”

Secondly, he notes, this is the first pandemic of the social media era. That makes the spread of “misinformation and disinformation” easier, and challenges health professionals to use behavioural science and social marketing techniques to cut through the noise and the fatigue.

That makes this pandemic different than, say, the Spanish flu pandemic of 1918-1919

Liberal MP Kirsty Duncan is an expert in pandemics, the environment and human health, and wrote a book on the Spanish flu. She says it’s hard to compare the two time periods and how pandemic fatigue factors in. In 1918, “the flu came at the end of the (First World War). People had suffered for four years. There was a shortage of medical personnel because doctors and nurses were serving in the war,” she said.

“Things were done differently in different places. Some places had masking, some places closed businesses, other places closed schools. There was no flu vaccine, no antiviral drugs, no antibiotics. Today scientists are working around the clock for preventives.”

Njoo said while we await a vaccine, Canadians need to stick to what works.

He called the #COVIDZero campaign – an idea advocated by some doctors to drive cases down to zero — “a nice, aspirational sort of a goal or objective.”

But he said we need to consider the “practical aspect” or “feasibility” of it, and “balancing all of the sort of unintended consequences of it.”

“I think what needs to happen is maybe a bit of a surgical, targeted approach, maybe a combination of still pushing for people to do the right things in terms of personal behaviour” and, as seen in jurisdictions like Nunavut, short-term lockdowns.

That, and provinces need an aggressive “test-trace-isolate” strategy in place, he said.

Testing “hesitancy” is a hurdle for officials to overcome because people are worried about being stigmatized, facing discrimination or job security challenges. Njoo said some provinces have asked for extra human resources for contact tracing from the federal government but it’s hard to integrate them into local efforts.

At the end of the day, said Njoo, combating COVID-19 relies on individual behaviour.

“It’s not only government or public health authorities alone, leaning on the hammer, that’s going to address this. It’s going to be every single person.”

Tam told reporters Wednesday that another set of federal modelling scenarios will be presented Friday, and she suggested Canadians can still “be successful again if we rapidly get the resurgence under control.”

Tonda MacCharles is an Ottawa-based reporter covering federal politics for the Star. Follow her on Twitter: