Pandemic curve to flatten by mid-June in central Canada, model predicts...other provinces way ahead

AboutAnything  | Greg McComb


   As Canada hits the mid-point of the second month of the coronavirus pandemic, the question on the lips of the quarantine-weary is: when will this thing end!? Several provincial premiers have provided tentative plans for easing of lockdowns as conditions improve, however, we have not heard any hard-and-fast dates....and there is a reason.

Photo by Jusdevoyage on Unsplash

  Although medical experts have a general idea of how the coronavirus virus spreads - the famous COVID-19 curve - much of this movement is random, so it's difficult to know how the disease will unfold over several months. 
 
    Many forecasts done early on by both federal and provincial governments have been well off the mark, most large overestimates of deaths and cases. As we are half way through the pandemic, more data is available to improve forecast accuracy.....so, as promised in my last blog, I took a crack at one. During a deep data dive, I came across an important aspect of this forecast that needs to be highlighted. I'll talk about this first.

Canada forecast is really a forecast of Quebec, Ontario...many provinces have already bottomed out

   As I combed through the coronavirus data, one thing that stuck out was how the vast majority of pandemic deaths were in either Quebec or Ontario; with a small percentage in other provinces. 

Data sources: Public Health Agency of Canada, Ontario and Quebec government reports and databases * Four Toronto-area Public Health Units: Toronto, York, Peel and Durham

The bar graph (May 3) above shows 93% of COVID-19 deaths (3,505 out of 3,760) were in central Canada, including the 'hot spots' of Montreal (1,410) and Toronto (762). Five provinces and three territories had less than 10 deaths. While B.C. and Alberta had small outbreaks: combined, those two provinces had 1/6 the deaths of Montreal alone.

  As discussed in the last blog, the virus spread quickly in Italy and the United Kingdom because they have large, densely populated cities with a lot of viral-laden international travelers traipsing through. The reverse is true for the Prairies, Maritimes and northern territories. Separated by thousands of miles from major cities,  their isolation saved them from any major outbreaks.

  This is important because it means the 'Canada' forecast presented here essentially becomes a forecast for central Canada, not other provinces. The case-based pandemic curves for four provinces illustrate this

Graphs generated by: ctvnews.ca/health/coronavirus

point, (left, April 28). While much is being discussed in the media about curve 'flattening,' these provinces (SK, MB, NB and PEI) have already peaked and come down to less than 10 cases-a-day, the watermark discussed by healthcare professionals to start loosening quarantines. P.E.I. and New Brunswick haven't had a COVID-19 case in several days.  This is likely one of the reasons Saskatchewan is discussing opening up its economy in early May, while Ontario's education minister said schools will stay closed until the end of May.
      
    Pandemic curve to flatten by mid-June in central Canada
                        
 So, back to the forecast model (updated May 4):  the results are in the bar graph below and I will walk you through those before explaining the methodology. The graph below is Canada's COVID-19 curve with the blue bars on the left real data, and the red bars a forecast, based on a 'quick-and-dirty' simulation I developed.

 Forecast model predicts flattening of pandemic curve in mid-June, with two-thirds the deaths of optimistic scenario in federal model.

Data sources: Public Health Agency of Canada (blue), date forecast by author (red)

     Like other COVID curves, this forecast curve follows a pattern: a rapid increase in deaths/day starting at three deaths on March 16th, peaking at 207 deaths on May 1st. Next, is the oft-repeated 

Photo by visuals on Unsplash

'flattening' (horizontal black line) in the middle - which should last about three weeks. We're are near the end of that now. Next, a gradual come-down should last about six or seven weeks, with deaths/day dropping from just over 150 deaths/day to less than 20/day by mid-June. Notice two things: the model predicts regular weekly 'waves' or cycles in deaths -- and the curve is not symmetrical: the left-side has a sharp incline while the right is less sloped, and so has a slower decline in deaths.

So, there are two important findings from this model: 

• The coronavirus outbreak is forecast to wind-down in mid-June, with deaths/day leveling off below 3/day by June 18. 

•  Total deaths from this 'first wave' are estimated at 7,107 or just over 7,000 deaths. That's about two-thirds the deaths predicted by a Public Health Agency of Canada (PHAC) model published in early April. The PHAC model predicts 11,000 deaths for an optimist  scenario that assumes 2.5% of the population is infected over the course of the pandemic. For 5% infection, PHAC's model predicts 22,000 deaths.

                        The methodology: how'd I do that?
  
     In my last blog, I explained the nuts-and-bolts of my coronavirus

methodology: I use deaths/day, rather than cases because of

Andre Ouellet on Unsplash

reliability issues with cases, and I assumed a pandemic starts with at least three deaths. The exceptions are the case-based pandemic curves of four provinces, SK, MB, NB, PEI. There weren't enough deaths in those provinces to make a curve. With one exception, the graphs are generated by the author using data sources sponsored by governments or university researchers. Those sources are cited under each graph. As for the forecast model, the logic behind it follows: 
    
    There are many pandemic curves, especially for the Spanish flu of 1918. However, the COVID-19 curve has a unique signature based on how infectious the virus is, and mortality rates. Therefore, what is required is an existing curve or curves to base my forecast on.  Both Italy and Spain started their pandemics earlier than Canada so in recent weeks we got a glimpse into what the 'back

Italy's COVID-19 curve  (source: worldometers.info)

  end' of a COVID-19 curve looks like, (see graphs to the left). Using a mixture of 'black art' and statistics I merged those curves to forecast the last 1 1/2 months of Canada's pandemic curve. For example, I took an average of the slopes of Italy and Spain's curves -- and estimated the length of

Spain's COVID-19 curve (source: wordometers.info)

Canada's flattening taking into account what happened in those countries.  As well, I borrowed the wave-like tendencies of both curves as best I could. As I said, this methodology involved a bit of 'black-art' so there was no one formula I used for the simulation. It was a series of formulas cobbled together in a spreadsheet.

      One last thing, a disclaimer: I reviewed pandemic curves from many other countries and although they all roughly take the shape a COVID outbreak, each is unique.  For example, curves in Sweden and Germany have wave-like properties but the waves in both are much steeper. 

Photo by Macau Photo Agency on Unsplash

A similar shift could occur in Canada, resulting in a much different forecast. As well, if Canadian provinces move to loosen quarantines or open up businesses too quickly, this could result in higher death rates. This model assumes "business-as-usual" for the duration of the forecast. Finally, few countries have 'finished' their pandemics so there is little data on how stealthy or resilient the coronavirus is, once quarantines end. Will cases and deaths spike again? Essentially, the world has become a large experiment, and we will learn about those viral properties in coming months.

    Seniors not youth are affected by the coronavirus....over 95% of  deaths are people 60 and over

  One other thing that stuck out during my data dive was how older people have been disproportionately affected by the pandemic, (see graphs below from April 20). 
      Not just a little, a lot.

Data source: Situation of the coronavirus (COVID-19) in Quebec, Quebec Health

     In Quebec,  diagnosed cases of COVID-19 (blue bars) are spread evenly among age groups: 60% are under sixty and the rest are senior citizens, (40%).  The big difference is the survival rate of patients: younger people are healthier and have stronger immune systems so they get sick, but survive. Under one percent (0.2%) of  the 10,977

Photo by Michelen Studios on Unsplash

younger patients died, (see brown bars). That's in line with the regular flu.  Not so for seniors. Look at the blue/brown bar coupling on the far right, COVID patients over eighty years old. It shows this age group makes up one-fifth of diagnosed cases, yet they form 71.1% of deaths. In raw numbers, 623 of the 877 people who died from the coronavirus were the eldest age group, over 80. With weakened immune systems and comorbities like advanced cases of heart disease or diabetes, older seniors don't last long once infected. 

    The same thing is happening in Ontario, their graph is like Quebec (see graph below). In that province, 20.9% of diagnosed COVID

Data source: COVID-19 in Ontario, Public Health Ontario

cases were for people over 80, while 67% of total deaths are for this elderly group. By the numbers, 416 of the 622 total deaths were seniors over 80. 

 Over the past month, we have heard over-and-over about how this crisis has unfolded in senior homes, with dozens of deaths occurring in a single residence once an infection gets hold. This has been the most tragic part of this pandemic; especially the fact these parents and grandparents had to die in isolation, without the support of family members. The statistics don't tell this story...a complete overhaul of seniors' housing policy is-in-order.

                Pandemic policy over the next few months

   So, what does all of this mean for pandemic policy?  The federal government wants a phased and coordinated approach with the

Photo by Nathan Dumlao on Unsplash

provinces as Canada opens up over the next few months.  This makes sense.  As discussed above, provinces with pandemic curves that have 'bottomed-out' should end their lock downs first and act as test-cases for the rest of Canada, while 'hot spots' like Montreal and Toronto go last. Close monitoring of the early movers will let other provinces know just how fast-or-slow they can go, as they lift quarantines and get their economies moving again.

Second, the age analysis showed a stark divide between how old-and-young people react to a coronavirus infection.  Older people are extremely vulnerable while the young get sick, but survive.  As quarantines open, this would suggest that senior citizens (especially those eighty or over) should be the last to roam around freely in public: they should keep a social distance, and wear non-medical masks.  In contrast, society should be less worried about younger people, especially those under forty. With precautions, re-opening elementary and high schools could be done in an early phase.

  Finally, I have written little about the massive costs to the economy of closing everything down during a pandemic. Pandemics involve a harsh trade-off  between saving peoples lives during lock-downs, on the one hand -- and crashing the economy with millions of jobs lost, on the other.  Using statistics and graphs, I will try to try to make sense out of this in my next blog...

Email: gregmcc07@gmail.com




 
  

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Canada is a world leader containing the coronavirus outbreak...why aren't we talking about it?

AboutAnything  | Greg McComb

   As the world moves into the first full month of the coronavirus pandemic - near peak curve - we get an early glimpse at the oft-repeated COVID-19 curves around the world. 

Photo by Julian Wan on Unsplash

No doubt once the pandemic is over, there will be study-after-study about the disease and the measures taken to eradicate the scourge, whilst balancing the needs of health against economic costs, essentially on the head of a pin.

    One thing is for certain: many researchers will be scratching their heads wondering how and why the self-effacing nation of Canada fared so well, compared to pretty well any other Western country. The early returns are surprising, although not altogether unexpected. 

Coronavirus deaths in all of Canada are a fraction of New York City, a pandemic hotspot (Daily COVID-19 deaths, Canada vs. New York City, March-April 2020)

     The bar graph above compares Canada to the pandemic hot spot of New York City, where daily news reports count the dead in the thousands, and State officials complain about shortages of breathing machines, grave sites and morticians. Only a few hours north in Canada's national capital of Ottawa, the city's public health department reports only a few deaths-a-day approaching peak pandemic in mid-April. The outbreak has pressed city hospitals into action, but there have been no significant shortages. 

    The graph illustrates how starkly different the pandemic is playing out in the two countries.  Daily deaths in only one city - New York - are multiples higher than all of Canada, even though Canada's population is four and a half times larger.  Take day 20 of the pandemic: New York City (orange bar) had 421 deaths compared to 23 deaths in the ten provinces and three territories of Canada, (blue bar).  Throughout the pandemic, Canada's deaths have been a fraction of New York city. (And the death counts may be much higher in New York city, as officials in mid-April said nearly 4,000 at-home coronavirus deaths weren't recorded by firefighters and paramedics).

  Yet you wouldn't know it listening to public officials. In early April, Canadian public health officials estimated a high-end of 22,000 deaths

Photo by Kelly Sikkema on Unsplash

country-wide, even with social distancing and closures. While Alberta suggested 6,600 people could die in that province alone, if people don't practice protocols for social distancing. That's six times the number of deaths in all of Canada as we approach the half way point, (1,006, April 14th) -- in only one province. Ontario had similar dire projections and suggested deaths of between 3,000 and 15,000, such a scenario providing justification for a further tightening of protocols, including closure of sports fields and playgrounds. In contrast, Quebec's Premier Francois Legault struck an optimistic chord saying his analysts suggest outcomes similar to Germany, one of the recognized world leaders in pandemic management.

                      Methodology: know it's boring but need to explain... 

    So, I don't want to lose you, but I need to talk briefly about methodology. There are many approaches and statistics floating around. So, I will explain my approach before moving to the main part of the article in which I compare Canada to other Western countries.

First off, all the graphs are generated by the author using data 'scraped' from reputable websites sponsored by governments or university researchers, such as the data aggregator website: 'worldometer': https://www.worldometers.info/coronavirus/  or New York City's website: https://www1.nyc.gov/site/doh/covid/covid-19-data.page. Second, while most COVID-19 curves use daily case data, my view is these numbers are unreliable because of: 

i) day-to-day variability in testing within countries, e.g. a testing push would result in case 'spikes,'  and ii) variation in testing across countries. For example, Germany tests 15,730 people per million pop., (see graph above) more than double the U.S., (7,101 tests). Using these 'raw' cases would result in inflated case numbers for Germany.  A better measure for COVID curves is daily deaths: it doesn't have the biases associated with testing, and it also measures how good a country is at social distancing measures and treating patients, once a person gets infected. When it gets down to it, whoever lives or dies in a pandemic is what really counts.
   
    Third, day counts are used on the horizontal axis, not actual dates. The counting starts (1, 2, 3, 4..) on the first day a country records at least three deaths. Sounds a bit random but the data often shows a single death, break, another death, and so on. It's only when 3 or 4 deaths occur that the pandemic sets in. The advantage of this approach is that it ensures

Photo by Fusion Medical Animation on Unsplash

daily comparisons between countries are done at similar progressions on their pandemic curves. Most pandemics started in mid-March* with the exception of Italy, which started on February 29th. 
        
      Finally, daily deaths in each country are 'weighted' for population with the metric: deaths per 10 million population. This ensures a fair comparison so that more populous countries like the United States (pop. 331 million) are not directly compared with smaller countries like Sweden (pop. 10.1 milllion) without adjustment. If this weighting isn't done, the U.S. would appear more worse off than it actually is. 
     

                           Country comparisons: Canada kicks COVID butt.. 

    So, the methodology has been set, and I will now use it to compare Canada's pandemic performance with six other western countries: UK, US, Germany, Italy, Sweden and the Netherlands. These countries were

Photo by Martin Sanchez on Unsplash

chosen to be representative of differing pandemic policies and outbreak progressions. As an example, Italy, France and Spain had similar rapid progressions of the coranovirus outbreak and resulting deaths, so Italy was chosen to be indicative of this group.  Germany was chosen for its rigorous management of the outbreak including extensive testing and monitoring; while Sweden and the Netherlands have similar "herd immunity" policies: less stringent social distancing and closures with the goal to make the population immune faster than quarantining. 

       The U.S. was chosen to compare Canada to its neighbor, a country with similar economic conditions but lacking a national healthcare system. A significant percent of the U.S. population (8.5%) doesn't have health insurance, while others - even with insurance - have constrained access to healthcare due to high, unregulated costs for drugs, doctor visits and hospitals stays. As ground-zero for the coronanovirus, China has the largest and most complete set of data, however, it was left out due to data reliability issues raised by numerous researchers. Finally, the countries were split into two graphs for ease of interpretation, e.g. a less 'cluttered' presentation.

Coronavirus deaths in Canada are much lower than the United Kingdom and United States, lower than Germany most days (Daily COVID-19 deaths/million, Canada vs. Germany, U.K. and U.S., March-April 2020)

    So, my motivation for this article was a 'hunch ' or hypothesis  that Canada is doing a better job at managing our coronavirus outbreak than what our public officials are letting on. This analysis seems to prove that out. Adjusted for population, Canada has far fewer deaths than the United Kingdom and the United States, and less than Germany most days (see graph above). Even as Canada (blue bar) approaches peak pandemic, the deaths/day for every ten million people ranged from 15 to 30 people, compared to deaths of over a hundred in the United Kingdom (grey bar) and 50 to 60 deaths in the United States, (yellow bar). Even Germany, which is held up as a leader in pandemic management consistently had higher daily deaths/10M than Canada for all but a few days.
    
   Despite having an excellent national health service (the NHS), the United Kingdom had ten times as many deaths/10M than Canada on some days. For example on day twenty-two, Canada had 11 deaths/10M compared to 104/10M deaths in the U.K.  This is early days, but the fact the U.K. is densely-populated with an international capital, London, likely contributed to the rapid outbreak of the virus. That, and the fact the UK government initially tested the herd immunity policy - with lax social distancing - before switching to tighter quarantines.

    United States is a tricky one for country comparisons. Although news reports frequently broadcast that the U.S. has the most deaths in the

Photo by Jon Tyson on Unsplash

world, those same reports rarely cite the fact the U.S. also has one the largest populations. At 331 million, the U.S. population is five times larger than both the United Kingdom (67.9M) and Italy (60.5M). Thus any 'raw' reports of deaths in the U.S. greatly inflate outbreak severity. That's why in this population-weighted graph, daily deaths/10M are 1/2 to 1/3 lower in the U.S. (yellow) than in the United Kingdom (grey). That said, there are numerous pandemic 'hot spots' in the United States, including New York city, the subject of a case study at the start. 

      The next graph (below) compares Canada to three other countries - all European - where the pandemic got an earlier start with more severe outbreaks. Canadian population-weighted deaths (blue bar) are a small fraction of deaths in all of these countries: Italy, (yellow) Netherlands (orange) and Sweden, (grey).

Coronavirus deaths in Canada are a fraction of  Netherlands, Sweden and Italy         (Deaths/10 M pop.) 

     With the earliest outbreak, Italy had the world lead in 'raw' deaths for several weeks, stemming that tide by going into a strict lock down after 10 days. Italy's daily deaths were multiples higher than Canada throughout the pandemic: for example, on day 23, Italy had 108 deaths/10M deaths compared to 15 deaths/10M for Canada. It's still early days, but reasons for Italy's high death rates include: the mass importation of the virus from a large tourist population that visits their numerous historic sites and scenic cities; an older population more susceptible to the disease and a 10-day delay enacting a strict quarantine.

    Sweden (grey) and the Netherlands (orange) are often reported as 'experiments' in herd immunity, a policy with more lax social distancing

Photo by Jonathan Brinkhorst on Unsplash

policies and fewer business closures. The 'raw' deaths in these two northern countries are much lower than hot-spots like Italy and Spain, and so are rarely reported in the media. With population-weighting, however, deaths in these northern countries are actually close to Italy. On day 23, Sweden had 113 deaths/10M, Netherlands had 96 deaths/10M while Italy had 108 deaths/10M. It is surprising that countries with such different pandemic policies have similar death rates, although Sweden and Netherlands have greater freedoms and their economies may snap back faster with fewer closures. 

  As for Canada, my country has consistently had lower deaths than all other countries surveyed during the pandemic: I joked in the subhead, "Canada kicks COVID butt.."  Why is this so?  One of the main reasons is that we have a solid taxpayer-funded national healthcare system. People are healthier to start with so we have fewer people with the comorbidities associated with COVID deaths, and our healthy immune systems are able to fight off the virus. Second, Canada's population is widely dispersed over a large geographic area, making it difficult for the coronavirus to spread from a 'hotspot' like Montreal to the Maritimes, where there are few deaths. Third, Canada's health system is well-funded with plenty of hospital beds, ventilators and - after some emergency air-

Photo by Toni Reed on Unsplash

lifts - medical masks. There are few shortages in Canada. Just across the border, as we approach peak pandemic the United States is failing on all these fronts: it has fragmented, high-cost healthcare so people aren't as healthy and access is limited. Critically, there are shortages of  life-saving ventilators and hospital beds due to lack of funding. On top of that, the U.S. administration and states dithered over social distancing measures - keeping Florida open for spring break in mid-March, for example - while Canada moved quickly to close the U.S. border and quarantine Canadians, especially those returning from abroad. I know, I was one of them. I was isolated in my house for two weeks,  after I was forcefully told by the Canadian government to return home from my winter vacation...pronto!  

   It's still early days, but one of the reasons Canada is doing well may be that our quarantine measures are less strict than many European countries which essentially imprison citizens in their houses or apartments.

Photo by MARCIN CZERNIAWSKI on Unsplash

Canada's measures allow us to social-distance walk, bike or run for exercise, and a large number of essential services have stayed open such as  auto mechanics, limited bus service and many take-out food restaurants. I bought a social-distanced sub the other day, on one of my frequent walks. Although its early, this policy of "loose quarantines" may be one of the keys to Canada's success, as it allows people to get fresh air, sunshine and exercise needed to stay healthy and support a strong immune system necessary to fight off any viral infection. There is a possibly the ultra-tight quarantine in Italy is one of the reasons for so many deaths in that country. It did not allow people to walk in streets or parks for exercise, and kept people close in small apartments where they are more likely to get infected from another family member. 


         As for policy, the analysis in this article in no way should be interpreted as justification to open up quarantines and loosen social distancing in Canada. COVID-19 is a serious-deadly disease, especially for seniors. Hundreds have tragically died in senior residences in Canada over the past month. My view is the Canadian quarantine measures should be loosened only when we reach the bottom of the COVID curve, (less than 3 deaths) likely around mid-to-late May (see next article for forecast) -- and then gradually to ensure Canada does not experience a second wave. Canada has done well managing COVID, with the lowest deaths in the world -- this management should not stop. 

    As for the question in the headline: Why aren't we talking about our success? You'll have to ask the Canadian government and provinces that question.  I really don't have a clue....I can only guess that analysts and policy wonks need to do more in-depth international comparisons, rather than presenting inflated death forecasts...these are really scaring people!

Email: gregmcc07@gmail.com




 
  

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