Was it luckor was New Brunswick actually quite good at responding to COVID-19?

New Brunswickand its Atlantic neighbours are emerging from the worst of the pandemic, having avoided the more severe waves of infection seen elsewhere.

It's a success that has been viewed with envy in other parts of Canada.

But what drove it?

Halifax epidemiologist Kevin Wilson says it was clearly the willingness of public officials to lock down quickly and keep a lid on transmission, especially last fall.

"It was not taken for granted that the virus would wash over us and be this omnipresent force in our lives," he said."There was this sense that we could totally get this under control if we put the work in."

In April 2020, experts told CBC News our relatively lower case rate at the time came from a mix of good policy and what we called "demographics and dumb luck."

Put simply, the theory went, our lack of urban density, mass transit and major travel hubs deprived the virus of easy opportunities to spread.

Chief Medical Officer of Health Dr. Jennifer Russell was never a big fan of that theory.

"I don't think I necessarily agreed with the assessment at that time in terms of luck and those kinds of things, because I know how hard people have worked to achieve the success that we have," she said.

"In order do that, we did have to work quite hard as a province, collectively."

A key moment was last fall, when cases began rising after a relatively COVID-free summer. Atlantic provinces locked down quickly, but others, including Ontario, adopted a wait-and-see approach, hoping the numbers would level off on their own.

Demographics helped, but were not enough

The experts we spoke to more than a year ago still believe demographics helped this region.

But over several waves in a 15-month period, that would never have been enough.

"The advantages are only meaningful to the extent that they are capitalized upon by political leadership, and they are only meaningful to the extent that the population as a whole runs with them," said University of Ottawa epidemiologist Raywat Deonandan.

"That's a decision, a policy decision. That pays huge dividends."

Striking estimates of higher case counts

Wilson has come up with a rough but striking estimate of those dividends.

He calculates New Brunswick would have had 9,599 more COVID-19 cases and 154 more deaths if its rates were similar to other parts of Canada with similar rural populations.

Atlantic Canada as a whole would have seen almost 33,000 more cases and almost 600 more deaths..

Wilson also estimates outbreaks in Atlantic Canada were 400 per cent more likely to be resolved than to persist and become part of ongoing high case numbers. Even adjusting for demographics, this region was 240 per cent more likely to see an outbreak end.

In other words, this region out-performed other areas with similar rural makeups. So that lack of density was not the deciding factor.

"There's a kernel of truth to it," Wilson said. "Toronto's going to have a harder time than Cape Breton or Miramichi, than a very rural, lower-population, lower-population-density area.

"But then you get these rural areas in other parts of the country that are 20 times worse than Miramichi, and it's: 'well, why did that happen?'"

The only logical explanation is the faster, stricter border closures and lockdowns that distinguished Atlantic Canada from those other parts of the country.

Border closures, limits on gatherings, contact tracing were key

Dr. Colin Furness of the University of Toronto's Institute of Health Policy saidthe Atlantic provinces "would have gotten clobbered if they didn't have excellent public health leadership."

The early and sustained closing of provincial borders to non-essential travel was "absolutely pivotal," he said. "Travel is one of our biggest risks."

Deonandan saidthe various limits on the size of indoor gatherings, from the household bubble of last fall to the "steady 15" of this spring, may have been the biggest contributor to reducing spread.

Russell credited contact tracing. Her team chased potential chains of transmission from positive patients to everyone they'd encountered, and beyond and then instructed those people to isolate to break the chain.

She said this was only possible, however, because the other measures were limiting the spread and buying the contact tracers time to do their work.

Political consensus avoided polarization over rules

The suite of restrictions was made possible by a broad political consensus, from the Higgs government to other party leaders to municipal officials, all of whom were vocally supportive of Public Health's approach.

"It definitely helped steer away from the typical politics that would sometime distract from a message that is really important in a crisis," she said.

Deonanddan speculated that the "ethic" of most Atlantic Canadians a less individualistic, more collective concern for the community as a whole also meant people were more willing to put up with those measures.

But he also said that "increasingly, I'm thinking political will might be the biggest factor."

Elected officials didn't hesitate because of, or pander to, anti-lockdown, anti-mask sentiment.

"There seems to be a willingness on the part of provincial leaders in Atlantic Canadian provinces to forgo the need to satisfy everyone, for the greater public health good."

It's still too early for a victory lap: Russell said that with restrictions now easing, "we could have another wave at one point but the proportion of people who will need to be hospitalized will be lower," thanks to vaccinations.

Zero was never the goal

Some observers outside the region have described the Atlantic Canada approach as "COVID Zero," an attempt to completely eliminate the virus from the region.

"Implicitly, Atlantic Canada had the policy of elimination," saidUniversity of Calgary biologist Malgorzata Gasperowicz, who has called on other provinces to adopt the same strategy. "Everything that was done in Atlantic Canada showed that."

Last month, Public Safety Minister Ted Flemming told a legislative committee that the goal was to limit spread to avoid stress on the health care system.

"Zero was never on the menu," he said.

Russell said thatwhile her "inside voice" was telling her to aim for elimination, she knew New Brunswick was "a different kettle of fish" than the places that pulled it off, such as New Zealand, an island nation.

"We were really just trying to protect our [hospital] resources, so whatever we needed to do to protect those resources, we were committed to doing it," she said.

"So if that meant the lowest number of possible cases, as close to zero as possible, great, knowing that zero cases can explode."