Agreed: The Formula for Containment is Isolation

"[The situation is such leaving me] deeply concerned by both the alarming spread and severity, and by the alarming levels of inaction."
WHO director-general Tedros Adhanom Ghebreyesu

"You can do it [aggressive social distancing] now or do it in three weeks when the ICUs are starting to fill."
"Countries that have done this successfully have closed schools. We can figure out whether it's overkill later."
Dr.David Fisman, physician epidemiologist, University of Toronto

"We need measures that, while painful for all, will slow social contact."
"And we need to stop feeling sheepish about it and just realize that some places [Italy, Iran] are in crisis and some are very likely in the days before a crisis that will be less bad if we slow down the virus to reduce peak demand on health care."
"We will not intervene as intensely as China, making speed more important."
"[A new study has provided the strongest evidence yet that] presymptomatic transmission is occurring." 
Dr.Marc Lipsitch, infectious disease epidemiologist and microbiologist, Harvard University

"[Researchers in Tianjin, China studied two detailed transmission clusters finding] that people can start infecting others three days before they start seeing symptoms themselves."
"One of the huge roles of these social distancing, self-isolation and quarantine measures is to try to stop those transmissions that could be happening even before people feel sick."
"This is still low risk in Canada right now. But I think it really underlies those preventive measures we can take. [When?] The answer is soon. But I don't know the cost implications of that. It has to be weighed in."
Dr.Caroline Colijn, professor, Canada 150 Research Chair in mathematics for evolution, infection and public health, Simon Fraser University

As COVID-19 cases continue to rise in Canada, experts are trying to slow the spread and prevent the health-care system from becoming overwhelmed. (Christinne Muschi/Reuters)

The question looms large ... if not now, when? With the World Health Organization finally declaring formally that COVID-19 is a global pandemic following weeks of health experts warning the world is in the early stages of one, countries around the world are girding themselves for the potential of a worst-case scenario. "There is so much unknown. People could be asymptomatic and contagious. This is the big difference from SARS", said Pierre-Gerlier Forest, director of the University of Calgary School of Public Policy -- of the situation where people became ill and then contagious, with SARS.

The novel coronavirus has demonstrated that it is able to spread wildly and does so before symptoms appear, and for up to two weeks after someone recovers, still shedding the virus and infecting others. Limiting human contact appears, at this stage, to be the primary foreseeable weapon in controlling the viral outbreak. China did so, brutally, and thoroughly, and it appears to have worked, with the numbers of newly diagnosed cases of COVID-19 steadily declining; most of those newly presenting originating from Chinese travellers outside the country, returning from destinations like Italy and Iran.

Microbiologist and infectious disease specialist Dr. Allison McGeer is pleading with Canadians to be vigilant about the 'boring stuff' — such as handwashing, staying home when they're sick and coughing into their elbows. (Evan Mitsui/CBC)

According to Dr.Forest, ultimately the goal is the reduction of the number of people that one single infected person can infect, to less than one. "If you can bring it under one, the epidemic starts to dwindle. The question is how to do it", and earlier rather than too late. Discovering who is spreading the disease is made infinitely more difficult when you throw in the equation that people can be asymptomatic, yet spread the contagion. "The case for social distancing is extremely strong", emphasized Dr. Forest.

Without public health intervention, pointed out Dr.Fisman who with his team's model for Canada, saw an overall attack rate of 70 percent among the population hit by the virus. That's an immense number of people to be felled by a virus, one that is potentially fatal for the elderly and the health-impaired. The emphasis on containment is public health intervention, finding and isolating at least fifty percent of mild cases through testing to allow a significant drop in the attack rate.

And it is envisaged that aggressive social distancing; sporting events played behind closed doors, people working from home, video conferencing, cancelling of concerts, no mass gatherings, shopping at off-peak hours and closing all schools among the many and varied decisions taken to minimize social contact.The goal is "flattening the curve", retarding the number of new infections and the spread of a virus that has already upended the lives of millions.

International researchers studied the virus incubation period -- held to be the time between exposure and the appearance of symptoms -- and serial interval, the time between someone becoming symptomatic and those they infect themselves becoming symptomatic. Two detailed transmission clusters were the focus of study leading to the finding that "people can start infecting others three days before they start seeing symptoms themselves" according to Dr.Colijn.

Any imposed restrictions on individual freedoms according to the federal pandemic plan in Canada, must be proportional to the magnitude of threat. "This principle of 'least restrictive means' should always be a consideration when enacting social distancing measures", reads the governmental plan.

And as a demonstration that no one is immune from this virus, Sophie Gregoire-Trudeau, wife of Canada's prime minister has been diagnosed with COVID-19. She had just returned from a trip to Britain to attend a convention at which she had a speaking engagement. She and her husband, Justin Trudeau, have entered self-isolation. Joining a lengthening list of public officials in self-isolation.

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  Liberal MP Anthony Housefather, Natural Resource Minister Seamus O’Regan, and 
  International Trade Minister Mary Ng are also in self-isolation.