Joanne Liu is a physician and the former international president of Médecins Sans Frontières.

Canada is about to experience the full brunt of the COVID-19 pandemic. Most Canadians have no idea how overwhelming a pandemic can be.

With hundreds of Médecins Sans Frontières (MSF) colleagues, I have fought numerous epidemics, namely one million cases of cholera in Yemen and the devastating Ebola outbreak in West Africa, where 28,000 people were infected and more than 11,000 lost their lives.

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Looking at the looming threat of COVID-19 , here is what is keeping me up at night.

There is no room for wishful thinking. The right mindset is to prepare for the worst-case scenario. While doing everything we can to avoid it, we must be mentally and organizationally prepared to deal with the conditions that are rocking Italy and Spain. In the best-case scenario, we will be overprepared – a small price to pay. In the worst-case scenario, we will be ready to save many more lives than if we were not fully prepared for the worst.

There are three steps that must be taken now:

1. As much as possible/feasible, we need to set up medical facilities dedicated only to COVID-19 patients: either stand-alone structures or a separate hospital within a hospital. It is tempting to try to manage COVID-19 cases within existing structures. This might work where case numbers are low. But when the numbers become overwhelming; when all beds are occupied by COVID-19 patients; when all stretchers in the hallway are filled by COVID-19 patients; and when very sick COVID-19 patients are queuing for ventilators, chaos will take over and foster cross-contamination.

There needs to be a dedicated COVID-19 area and a non-COVID-19 area with no interchange of staff or patients between the two .

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By separating patients, and by having separate staff, Canada can significantly decrease the risk of medical facilities becoming centres of amplification. These will be overwhelmed in a worst-case scenario, but at least they will be overwhelmed apart from the rest of the hospital system.

Dedicated staff in dedicated facilities will more quickly develop the individual and collective expertise to handle COVID-19 patients. Dedicated staff may also reduce the volume of personal protection equipment (PPE) required as staff will not go from one COVID-19-positive patient to a non-COVID-19 patient.

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2. Our health-care workers are our best and last line of defence in a pandemic. For their sake and ours, we need to protect their physical and mental health.

We need to make sure that our medical staff will always have the right PPE available at all times.

In the worst case, we need to help them decide who will perish or pull through. . A physician should not have to make, in an ad hoc way, the excruciating decision of who gets a ventilator – the 78-year-old with diabetes or the 55-year-old with no past medical history and three children. Yet this is what is happening in Europe today.

There should be guidelines prepared to guide doctors with this sort of complex and harrowing decision-making, should it become necessary to do so.

We need to help health-care workers protect and take care of their families. Should medical staff stay away from their loved ones? If medical staff are infected by COVID-19, where should they be hospitalized? Can health-care workers and their families count on being fully supported if they fall gravely ill?

Being a health-care worker in a pandemic is a life-and-death issue – for some, unfortunately, death will inevitably ensue. Is the government ready to take responsibility for dependants as it does for soldiers who die at the front line?

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The mental pressure and anguish faced by health-care workers in a pandemic is unimaginably high. They must have access to psychological counselling and support.

3. We must ensure that critical care to non-COVID-19 patients is maintained.

During the height of the crisis, COVID-19 could get all the attention and monopolize all available resources. We have to make absolutely sure that highly treatable and preventable medical conditions do not become lethal.

We should not create a second-rate status for non-COVID-19 patients with acute needs.

In our fight against COVID-19, we have made economic and political decisions that would have been unimaginable a few weeks ago. We now need to confront the unimaginable on the health side and prepare for the worst.

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We need to do it now. Because the full force of the pandemic is coming.

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