Author: Ernie Dainow

The first blog article on the Delta variant, on June 18, 2021, showed an increase in cases in July but declining throughout August and beyond. This was more of a bump than a fourth wave.
https://anydaynow.blog/delta-variant/

The blog on July 19 revised the model projections by recalculating herd immunity for the delta variant when 80% of the population was fully vaccinated. Then vaccination rates were projected and herd immunity was predicted in August in Canada.
https://anydaynow.blog/herd-immunity-recalculated/

But here we are at the end of August and daily cases in Canada are still increasing.

What happened to herd immunity?

The big change was that at the beginning of August, the rate of vaccination decreased in Canada. On the current trajectory, 80% fully vaccinated will not be reached until October instead of August.

https://tinyurl.com/bn353kvy

This change results in a fourth wave that peaks with about 6,000 new cases per day at the beginning of October, 2021. After that, cases decline to a negligible amount.

It’s amazing how many people have became experts in public health in less than a year. Many of these people, like state governors and provincial premiers, use their newfound knowledge to make major decisions that affect the health of millions of people. Professionals working in the field of public health generally have at least six years of training, for a medical degree and/or a master’s degree in public health. Does anyone believe that politicians are so much smarter than health professionals that they can become experts in a year?

Public Health covers a very wide range of areas, from managing and monitoring disease to biosafety and security.
https://www.canada.ca/en/public-health.html

Contrary to what some people might think, public health did not just evolve in the last year with the onset of the coronavirus pandemic. Public Health has been an evolving scientific discipline for a long time.

Lockdown and other social distancing measures are not unique to the coronavirus pandemic. There are many articles and books about how plagues were dealt with in the past.

“From the onset of the Black Death in 1347-48, Italian cities which faced the Mediterranean, an epidemic sea, constructed a complex and articulated health defence system which was an example to all other western countries. The cornerstones of this health defence system lay in quarantine, sanitary cordons, lazarets, disinfection, and in the social regulation of the population at risk.”
https://pubmed.ncbi.nlm.nih.gov/19227587/

“Popular narratives continually included grievances about the cruelty and inequity of quarantine and the militaristic nature of its implementation. Despite these objections, quarantine remained a staple of the government response to plague outbreaks throughout the seventeenth century.”
https://pubmed.ncbi.nlm.nih.gov/22611587/

The Public Health Act in Britain was passed in 1848. It aimed to improve the sanitary condition of towns in England and Wales by placing the supply of water, sewerage, drainage, cleansing and paving under a single local body with the General Board of Health.

The Vaccination Act 1853 introduced compulsory smallpox vaccination in England and Wales.

The Infectious Disease (Notification) Act 1889 mandated the reporting of infectious diseases to the local sanitary authority, which could then pursue measures such as the removal of the patient to hospital and the disinfection of homes and properties.

The first public health organization in the U.S. was in New York City in 1866.

https://en.wikipedia.org/wiki/Public_health#After_the_18th_century

In 1905 the U.S. Supreme Court upheld the legitimacy of compulsory vaccination in Jacobson vs. Massachusetts. The Court compared the right to enact public health measures during an epidemic to the right of a government to defend its people from a military invasion. They compared the right to compel individuals to be vaccinated, whether they wanted to or not, to the power to conscript people to raise an army. This remains the major case in public health law today.
https://www.brandeis.edu/now/2020/may/smallpox-and-coronavirus-willrich.html

The current controversy raging over mandating vaccination for Covid-19 is at odds with long-standing principles encased in law going back over 100 years.

Why is there a debate over vaccine mandates? 

The various measures being proposed to mandate vaccinations are not compulsory orders requiring people to get vaccinated. They are just simple rules made for public health, that in specified areas, unvaccinated people pose a health risk to other vaccinated people in that space, and so unvaccinated people are to be restricted from entering that space. The space may be hospitals, restaurants, stores, or offices under the jurisdiction of a particular health authority. Such decisions are clearly within the bounds of public health authority.

Private companies also have the right to ban unvaccinated employees from the workplace for the safety of their employees. Many American companies, including those operating in Canada, require a medical exam as part of a job application. The information is not given to the employee but is used by the employer in any way they wish and may be used to deny employment.

One reason there is so much debate over vaccine mandates is that many public health officials have not taken initiative and leadership throughout the pandemic. Many have been working in a government bureaucracy for their whole career and they did not step forward when the pandemic was recognized to insist on instituting public health measures, even though that is supposed to be an important part of their job. They continually deferred to the political leaders, even when those leaders made bad public health decisions. A good example of this was David Williams, the chief medical officer of Ontario. He was a typical dry bureaucrat with little foresight or initiative and rarely challenged decisions made by Premier Doug Ford. In spite of criticisms and calls for him to resign, from many parts of the medical and public health community, Ford reappointed him for another term. However, shortly after starting his term, Williams finally saw the light and announced he would retire in June 2021.
https://www.cbc.ca/news/canada/toronto/ontario-top-doctor-pandemic-retirement-1.6046068

Only in extreme cases have public health officials overridden bad decisions made by politicians. One case of this was when Premier Ford in Ontario was very slow to bring in measures to control the large spike of the third wave. In response, the City of Toronto’s medical officer of health issued an order to close the schools, even though the Ontario Education Minister said the provincial government believed schools were safe and not sources of transmission of Covid-19.
https://www.cbc.ca/news/canada/toronto/toronto-closing-schools-covid-19-1.5976923

What should have been done?

If more public health officials had just done their job and issued orders to protect public health, without deliberating and knuckling under political pressure, a lot of bad decisions made in managing the pandemic could have been avoided. 

Restricting unvaccinated people from public places, such as hospitals, airplanes, trains, restaurants, shopping and office buildings where they are a health threat to others is just good public health practice, nothing more. The debate over requiring medical workers to be vaccinated is particularly ludicrous – people who go into a hospital for medical treatment should not be exposed to an increased risk of getting Covid-19. This has nothing to do with “personal freedom of choice”, it is fundamental public health where the health of the public is being protected. 

It is clear that a lot of people from citizens to people in power do not really understand what public health is and don’t feel it is an obligation and a priority of society, even though it is science that has been developed for hundreds of years and has corresponding laws that can be enacted by public health officials when necessary.

People who are demonstrating against vaccine mandates do not oppose the government requiring them to get a license to drive a motor vehicle. It is the law, and the purpose of the law is to protect innocent people from being injured by drivers who do not have adequate vision or safe driving skills. The purpose of public health is exactly the same – to protect innocent people from getting infected with a serious illness by people who are carriers of the disease.

In May, the blog showed that Covid-19 has a Herd Immunity threshold of 60%-75%. In other words, 60%-75% of the population must have immunity (from prior infection and vaccination) to prevent epidemic spread of the disease.

This was based on R₀, the basic reproduction number, being 2.5 for Covid-19 (green bar on this graph).

With the increase of the Alpha and Delta variants becoming the major coronaviruses in many countries, including the UK, Canada and the U.S., this has now changed.

The Alpha variant is 1.5 times more transmissible than the initial coronavirus.
The Delta  variant is 1.6 times more transmissible than the Alpha variant.

This increases R₀ to 2.5 x 1.5 x 1.6 = 6.0

Reading up from 6.0 on the horizontal axis of the graph we get a Herd Immunity threshold of .85. This means that 85% of the population needs to be immune. This is a big part of the explanation for the sudden spike in cases in the UK and the U.S.

https://tinyurl.com/76t5h6vn

The other part of the explanation is that while single vaccination rates went up sufficiently to protect against the Alpha variant, protection against the Delta variant really requires full vaccination. The immunity level of fully vaccinated people has not reached the 85% level in any of these countries. Add 10% to the numbers in the following graph to include people with immunity from prior Covid-19 infections to get the total immunity level for the population.

https://tinyurl.com/bn353kvy

The other big problem is that as the number of people vaccinated increases, there is a slower vaccination rate. People with vaccine hesitancy make up a larger proportion of the people who are unvaccinated. The graph above shows this as a decrease in the slope of the line. This has occurred in the UK and very significantly in the U.S. since mid-May. Canada does not show this slowdown yet.

A simple projection of the above chart, assuming these countries maintain their current vaccination rate, shows the following results for reaching herd immunity when about 80% of the population is fully vaccinated:

Canada in August
UK in November
U.S. in January 2022

Covid-Zero is a strategy to impose a range of restrictions including strict lockdowns and rigorous testing and tracing to drive transmission of Covid-19 to zero. Several organizations have been set up to promote this strategy to end the coronavirus around the world.
EndCoronavirus.org

It has had remarkable success in a number of countries, such as Australia, Vietnam, Taiwan and New Zealand.
Get Real Canada, Get to Zero

However, Australia’s success with Covid-Zero seems to have run into a roadblock. It seems like the Delta variant spreads too quickly for this strategy to continue working. Who would have predicted this a few months ago?
Why the Delta Variant Could End Australia’s Pursuit of ‘Covid Zero’

Many countries in Asia who have also done really well keeping Covid cases low are running into the same turn of events.
As Delta Variant Surges, Outbreaks Return in Many Parts of the World

As vaccinations increase in Canada and Covid-19 cases continue to decline, there is a general sense of optimism that the pandemic is almost over. However, reports from the UK on the rapid spread of the Delta variant, first discovered in India, provide an ominous forecast.

In the past, trajectories of the coronavirus in Europe and the UK have not been followed very seriously in North America. Our “experts” and political leaders have adopted a “wait and see” approach. This happened with the original coronavirus outbreak in March 2020, the second wave that started in September and the third wave (due to the Alpha, or UK variant) in March 2021. The result was that in most cases public health action was delayed and not optimal.

In a crisis, this is not the right thing to do. The right thing to do is to be prepared and plan for the worst. 

Here is what has been reported in the UK (June 11).
– 90% of new Covid cases are now the Delta variant.
– Cases are doubling about every 10 days.
– The Delta variant is 60% more transmissible than the Alpha variant, which makes it 140% more transmissible than the original Covid-19.
– The first vaccination is only about 30% effective; but the second shot provides 80% effectiveness.
– There are some cases of fully vaccinated people getting Covid, and dying.
https://www.theguardian.com/world/2021/jun/11/delta-variant-is-linked-to-90-of-covid-cases-in-uk

Modelling in the UK shows that a third wave of infections could rival Britain’s second wave from the Alpha variant. To counteract this, Prime Minister Boris Johnson delayed the final stage of easing lockdown restrictions for 4 weeks until 19 July.
https://www.bbc.com/news/uk-57476776

What’s the risk in Canada?

The last projection in the May 12 blog predicted “restrictions being removed in July. There is no surge and cases continue to decline to a negligible number”. 

But this did not include the Delta variant. It has now been added to the model using the characteristics of the Delta variant summarized in the following report, assuming 16% of all Covid cases are the Delta variant on June 18, rising to 90% in the first week of August.

In addition, the relaxation of controls was applied, using the guidelines that most provinces are following. These are the steps in the Ontario reopening plan, with at least 21 days between steps.

Step 1: 60% of adults vaccinated with one dose.
Step 2: 70% of adults vaccinated with one dose and 20% vaccinated with two doses.
Step 3: 70 to 80% of adults vaccinated with one dose and 25% vaccinated with two doses.
https://www.ontario.ca/page/reopening-ontario

Ontario, B.C. and Alberta entered Step 1 in the second week of June.
The model projects proceeding with
– Step 2 in the first week of July.
– Step 3 in the last week of July.
– Fully reopen first week of September.

Here is the picture with these assumptions.

So cases continue a rapid decrease into July but start to rise as controls are relaxed and the Delta variant spreads.

It remains to be seen which provinces delay advancing to the next reopening step when cases increase or just “wait and see”, allowing the Delta variant to spread and hoping that the increase in full vaccinations will reduce the spread in September.

What’s the risk in the U.S.?

The fully vaccinated rate is 44% In the U.S. compared to 14% in Canada. This means there is more resistance to the spread of the Delta variant. But all states except 4 have reopened completely which allows the coronavirus to spread more easily.
https://www.nytimes.com/interactive/2020/us/states-reopen-map-coronavirus.html

The U.S. could see a fourth wave similar to the one in Canada in the summer or autumn. There are also many regions in the U.S. that have very low vaccination rates. There will likely be several outbreaks in these parts of the country as the Delta variant spreads. 

How to keep up with the Delta variant?

You can easily follow the Covid-19 trend without waiting for a news report. Just watch this chart “New Covid-19 Cases per Million People” which is updated daily.
https://tinyurl.com/76t5h6vn

It clearly shows the Delta variant in the UK taking off on May 25. If the curve for Canada or the U.S. starts a steep rise like this, you know they are headed for trouble.

Herd Immunity occurs when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity. It is the point where the disease reaches an endemic steady state, which means that the infection level is neither growing nor declining exponentially.

At the beginning of the pandemic it was not clear if Covid-19 was like other viral infections and if people would acquire immunity after recovering from it. It was recently confirmed that this is in fact the case.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00675-9/fulltext

Here is a chart of Herd Immunity  for different diseases. Note that Covid-19 has a Herd Immunity level of 60%-75%.
https://en.wikipedia.org/wiki/Herd_immunity

R₀ the basic reproduction number is the average number of people that get infected by someone who has the disease. R₀ is basically a measure of contagiousness. It was measured early in the pandemic as 2.5 for Covid-19.

The Herd Immunity Threshold (HIT) is different for different diseases. It is calculated as  1 – 1/R₀

In December 2020, Dr Fauci stated that the real range to reach Herd Immunity is when 70%-90% of the population has immunity, instead of 60%-70%.
https://www.nytimes.com/2020/12/24/health/herd-immunity-covid-coronavirus.html

More recently the thinking has shifted to saying that reaching Herd Immunity Is unlikely in the U.S.
https://www.nytimes.com/2021/05/03/health/covid-herd-immunity-vaccine.html

What’s going on here?

It seems like some people are now using a different definition for Herd Immunity. Instead of “reducing the likelihood of infection” it is now being used to signify the point at which the virus disappears.

If we use the classic definition, latest statistics give a pretty good indication that the U.S. has achieved Herd Immunity. The new cases (and hospitalizations and deaths) have been in decline since April 15, down by 33% in three weeks. If there are no further surges and social restrictions can be removed, then this is Herd Immunity.

Note that for the first time in the pandemic, the new case rate in Canada has exceeded the U.S. Cases in Canada have flattened but not significantly declined. The difference is that the U.S. has had a much higher vaccination rate, and also a higher number of prior infections.

https://ourworldindata.org/explorers/coronavirus-data-explorer?zoomToSelection=true&time=2020-03-01..latest&pickerSort=asc&pickerMetric=location&Metric=Confirmed+cases&Interval=7-day+rolling+average&Relative+to+Population=true&Align+outbreaks=false&country=CAN~USA

The level of immunity in the U.S. on April 15, 2021 was 48%.
  (38% from vaccination plus 10% from people who had recovered from Covid).

In Canada, immunity was 25%.
  (22% from vaccinations plus 3% from people who had recovered from Covid).

https://ourworldindata.org/explorers/coronavirus-data-explorer?zoomToSelection=true&time=2020-03-01..latest&pickerSort=asc&pickerMetric=location&Metric=People+vaccinated&Interval=7-day+rolling+average&Relative+to+Population=true&Align+outbreaks=false&country=CAN~USA

Several months ago, the spreadsheet model I have been using since the beginning of the pandemic, projected herd immunity in the U.S. would occur in April 2021 with an immunity level around 50%, matching these actual statistics. This verifies that the basic logic in the model is in the right ballpark. 

To gauge what will happen going forward, these adjustments were made.

1 . To reflect the vaccine hesitancy that is occurring in the U.S. the average daily vaccination rate was reduced. The maximum number of people that get vaccinated was set to 70% of the population. 

2. To reflect the removal of pandemic controls, the reproduction number was increased to the Covid-19 basic number of 2.5 in mid-May.

3. The UK variant was set to be 90% of new cases.

The result shows the U.S. reaching 75% immunity in mid-May, based on 60% of the population being vaccinated with at least one dose. There is no surge and cases continue to decline to a negligible level. This is Herd Immunity corresponding to the more strict definition.

Since this is a national model, it does not reflect areas of the country where the vaccination rate is much lower than the national average, such as Alabama and Mississippi, where Covid outbreaks may continue to occur.

The forecast for the Canada model predicts cases declining in May. At the height of the third wave, this may not look likely, with major outbreaks still underway in Alberta, Manitoba and Nova Scotia. But because cases have been coming down in the large provinces (Quebec, Ontario, B.C.), the national average shows this trend, which will occur later in the smaller provinces.

The model predicts restrictions being removed in July when Canada reaches 74% immunity and vaccinations reach the 70% limit. There is no surge and cases continue to decline to a negligible number. This is Herd Immunity corresponding to the more strict definition.

The Covid-19 outbreak in India is pretty scary now, with a really steep increase in new cases and deaths in just a few weeks.

https://www.theguardian.com/world/2021/apr/19/what-do-we-know-about-the-indian-coronavirus-variant

There was an interesting article March 1, 2021 about why poorer regions like India and Africa did not have huge outbreaks of Covid-19. While many possible reasons were given, the overall conclusion was that it is somewhat of a mystery. It was written by Siddhartha Mukherjee, a brilliant doctor and writer who won a  Pulitzer Prize for the book “The Emperor of All Maladies. A Biography of Cancer”. This is a long article but worth reading, or listening to. It is not often that you will read such a well written piece on the pandemic.
https://www.newyorker.com/magazine/2021/03/01/why-does-the-pandemic-seem-to-be-hitting-some-countries-harder-than-others

Now there is a partial answer to the mystery. It took time for a mutation to adapt to the particular conditions of India. Now that it has, the virus is taking off.

The spike in cases in India is actually a similar trajectory (slope) as the UK variant was in Britain. But because the population of India is 20 times that of the UK, there is a huge difference in the number of people who are getting sick and dying. The UK variant peaked at over 50,000 cases. With a factor of 20, it is possible that daily new cases in India could rise to 1,000,000.

The UK was able to recover with a hard lockdown at the beginning of January and an aggressive vaccination program. Once the UK vaccination rate reached 50%, spread of the virus started to slow down. 

It won’t be easy for India to do this. They need to vaccinate over 500 million people to reach 50%.

https://ourworldindata.org/grapher/covid-vaccination-doses-per-capita?country=CAN~GBR~USA~IND

Typical estimates for herd immunity reported in the media are when 60-80% of the population has immunity. In fact my model shows much lower thresholds. Herd immunity depends on a combination of factors:

number of prior infections¹ + number vaccinated + transmission rate

¹A recent study has confirmed that people who recover from Covid-19 do in fact acquire immunity.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00675-9/fulltext

My U.S. model shows herd immunity at 50%, with cases starting to decline in mid April (as reflected in the graphs above).

If Canada can keep the transmission rate low at 1.1 we will see slowing cases when vaccination reaches 40% of the population, which will be mid May.

This model assumes that vaccines continue to work against the variants active in Canada. There’s plenty of evidence, from both vaccine clinical trials and real world data that all the vaccines protect against these variants, but there is not enough information yet about the India variant.
https://www.healthline.com/health-news/covid-19-vaccines-are-still-effective-amid-rising-number-of-variants

Another assumption is that Canada will receive vaccines according to the contracted agreements with suppliers.
https://www.canada.ca/en/public-health/services/diseases/2019-novel-coronavirus-infection/prevention-risks/covid-19-vaccine-treatment/vaccine-rollout.html#a4a

On April 16, 2021 Ontario extended its stay-at-home order, banned outdoor gatherings with people outside their household and shut down outdoor amenities like playgrounds, tennis and golf. It also stepped up enforcement powers for police in a bid to stem the exponential rise in Covid-19 cases. But it didn’t institute paid sick days for essential workers.

These measures are not based on science and do not make sense to most people. How many cases were there of Covid being transmitted at a playground?

A day later Ford reversed the decision to close playgrounds.

Here is the assessment from Ontario’s Covid-19 Science Advisory Table: “Without stronger system-level measures and immediate support for essential workers and high-risk communities, high case rates will persist through the summer.”

https://www.cbc.ca/news/canada/toronto/covid-19-ontario-april-16-2021-new-restrictions-modelling-1.5990092

Finally, doctors are speaking out more forcefully. It remains to be seen if this has any impact on these policies.
https://www.cbc.ca/player/play/1886237251529

“The root cause is the fact that the people in my ICU right now, who are essential workers or related to them, do not have adequate protection from the virus. The modelling was very clear.” (Dr. Michael Warner, Head of critical care at Michael Garron Hospital)

It’s worth listening to Rosemary Barton’s comments about Doug Ford. She is the CBC’s chief political correspondent, an astute observer of Canadian politics. It is obvious from what she says and her tone that she thinks that Ford skirting the truth and making the pandemic political is pretty despicable.
https://www.cbc.ca/player/play/1886559299598

Glaringly absent from the emergency measures to reduce the spread of Covid are restrictions on workplaces. The Workplace Safety and Insurance Board data indicated that more than 20,000 confirmed workplace cases of Covid -19 have been reported. Just since March 1, 2021, ministry inspectors have conducted 1,800 Covid -19-related field visits in the construction sector, issued over 3,770 orders on those visits and stopped unsafe work 11 times.
https://canada.constructconnect.com/dcn/news/government/2021/04/breaking-ford-announces-closing-of-non-essential-construction

The one workplace restriction brought in by Ford was to shut down some non-essential construction such as shopping malls and large office buildings. Note that this does not include the huge residential construction industry. So in a choice between increasing infections, hospitalizations and deaths or a 4-6 week delay in people being able to move into a new home, why did Ford pick increasing deaths? A delay in construction means losses of millions of dollars to developers.

The list of businesses that the province deems as “essential” is a really long list. See the bottom of the page in https://toronto.ctvnews.ca/ontario-orders-all-non-essential-businesses-to-shut-down-1.4864492

In response to a question from a reporter about closing more workplaces where we know transmission is occurring, Ford rejected it outright, saying that there is a “very deep supply chain” and many industries supply materials which are needed by essential services. He gave as an example that you cannot shut down the forestry industry because it supplies an important ingredient that is needed to make Aspirin.

It does not seem that any analysis has been made into this option. I’m sure that the pharmaceutical industry has enough inventory so that shutting down forestry for 4-6 weeks would not result in a shortage of Aspirin on pharmacy shelves. The same conclusion could be arrived at for many other “essential” services.

Using Ford criteria, a factory that makes paper clips could claim it was essential, because it supplies a product that is used in hospitals.

This makes it pretty clear that the fundamental problem with Doug Ford is that he is beholden to business interests. He needs their support to get re-elected. Even faced with a dire health situation and recommendations from many doctors and scientists, Doug Ford sacrifices public health for his own political interests.

Hopefully, enough people in Ontario will come to recognize this and never elect him for anything ever again.

At the end of March, about 30% of seniors aged 80 and up in Ontario had not received their shot. This was regarded as very low and a failure of the vaccine rollout. Many reasons were suggested for this.

https://www.cbc.ca/news/canada/toronto/covid-19-vaccine-ontario-booking-appointments-1.5958792

However, the article does not mention what has been one of the main problems. Many people just did not know how or where to get a vaccination. Often when a vaccination site opened up, it was word of mouth that notified people that they could register for a shot. I registered for my shot when I got an email from a friend at 11 pm one night. Of course, this leaves out many people who aren’t as well connected.

Many older people who got a vaccination were able to do so because they had a relative or a friend who negotiated the myriad paths to find out how to book a shot. Even computer literate younger relatives often spent hours scouring websites to locate a vaccination site that their relative/friend could use. I have heard these stories from many people. This has been a problem from New York to California as well as Ontario. 

Why has the vaccine rollout been so chaotic?

There is really no excuse for yet another case of really bad pandemic policy and management by government and public health.

Here’s a simple common sense approach that should have been followed (this example is for Ontario but is applicable to other jurisdictions).

Every person eligible for a vaccination in Ontario has an OHIP number (Ontario Health Insurance Program). The government has a database of all of these people. Each OHIP record has the name of the person, date of birth, address and phone number. So the Ministry of Health could have easily contacted every person in Ontario to give them clear instructions in advance on how to get a vaccination. 

Here is a simple letter that should have been sent out in November to everyone in Ontario with an OHIP number.

That was pretty easy, it took about 20 minutes to draft this letter.

You’d think that with a budget exceeding $1 billion for a provincewide vaccination plan, someone in the Ontario government could have organized this. Of course this plan would have to be followed up with a robust web server and phone answering service built to handle a large number of requests. In 2020, this was not rocket science.

Ontario did finally provide a central website for booking vaccines, but instead of in November it was not up and running until March 15.

As the number of variants of concern increase to 50% of all cases in many areas and Covid-19 case counts start to move up, there is increasing concern that we are at the start of a third wave in Canada and the U.S. In spite of these warning signals, governments continue to relax restrictions, which threaten to accelerate this trend. Many parts of Europe are already in the midst of a major third wave.
https://www.cnn.com/2021/03/19/europe/coronavirus-europe-third-wave-intl/index.html

Because the variants spread more rapidly than the normal Covid-19 virus, the  third wave can occur extremely quickly. This chart shows the rapid rise in the United Kingdom due to the UK variant that peaked in January and in Italy the sharp increase that has doubled the number of daily new cases  in three weeks.

This chart can be accessed with the following link where you can add other countries for comparison and follow the progress of the third wave as time goes on.
https://tinyurl.com/tw6pdb7a

Where is Canada headed?

In December a researcher at the B.C. Centre for Disease Control was reviewing the clinical trial data of the Pfizer vaccine and recalculated the efficacy of the first dose at 92% rather than 52% that Pfizer  had reported. She realized that with such a highly protective first dose, the benefits derived from a scarce supply of vaccine could be maximized by deferring second doses. This was reviewed by the National Advisory Committee on Immunization (NACI) and on March 1 they issued a strong recommendation that the second dose of all COVID-19 vaccines should be delayed up to four months after the first. All the provinces are following this recommendation.
https://www.cbc.ca/news/health/canada-covid-19-vaccine-delay-risk-1.5939134

This was an insightful and bold action taken by Canada. No other country has delayed second doses for 4 months. This almost doubles the vaccine supply in the country.

In addition, after various delays in vaccine deliveries there is a big increase in confirmed deliveries which will double the number of vaccines in Canada in two weeks.

These two changes in Canada’s vaccine rollout make a huge difference. The revised coronavirus model now shows a manageable third wave peak of less than 7,500 new cases daily. By May, the population immunity is about 40% and the number of new cases start to decline. Since Canada sustained daily cases of 10,000 in January 2021, this situation would not trigger a lockdown.

However, while the vaccination rate is increasing, more regions are relaxing restrictions. If the reproduction number increases by only 20%, the third wave peaks at 15,000 daily cases. This would probably trigger lockdowns in some areas of the country in mid-May.

In the second wave, most regions, especially Ontario and Quebec, delayed too long to bring in lockdown measures. If they had done this at the beginning of the second wave in November instead of delaying until the last moment in December, the lockdown period would have been shorter and the population could have enjoyed a December holiday season closer to “normal”.

The variant infection wave accelerated really quickly as shown on the charts for the UK and Italy. This characteristic delay to act by provincial premiers and their health ministries portend a bad outcome. So it’s no wonder that health experts do not trust that their own governments will handle the third wave very well. Sunnybrook, one of the largest hospitals in Ontario,  is building a field hospital in preparation for a possible third wave. This is being done with federal funds provided for such a purpose. The Ontario minister of health had no comment on this development.
https://globalnews.ca/video/7689345/coronavirus-sunnybrook-field-hospital-pops-up-amid-concerns-of-3rd-wave

Regardless of whether there is a third wave or not, here are some of the risks associated with the new variants.

Where is the U.S. headed?

The U.S. continues to increase its vaccination rate. The current trend will easily outpace the variants with no significant third wave. By May the population immunity is 50% and cases decline rapidly. 

However, this scenario is not likely. Already many states have removed all restrictions. If the reproduction number increases by 35%, the U.S. will have a third wave and daily new cases will increase to 185,000. In the U.S. there was a peak of 250,000 cases a day in January 2021. Only some areas particularly hard hit by a third wave would likely implement lockdowns.

This is a lot of cases and corresponding deaths, but the U.S. is able to sustain a high case and death count without resorting to tough lockdowns. This is distinctly different from Canada where cultural and political differences enable public health science to exert a stronger influence over business interests in determining lockdown policies.