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Hub Explainer: Why is the Delta variant so dangerous?


The original SARS-CoV-2 virus was responsible for the the large first wave of hospitalizations and deaths that overwhelmed an unprepared world. Most deaths were in the elderly who were inadequately protected.

In the absence of easy effective containment measures and vaccines, lockdowns were used in most countries to slow the spread of disease. In this initial wave, COVID-19 mortality was mainly a disease of the elderly or the unhealthy. 

The virus is made up of various components and proteins as shown below. The spike protein is the most important since it is the entry point for infiltrating cells and then using the cell’s machinery to extensively replicate and spread. 

As time went on and infection rates increased, the viral replication was sometimes imperfect leading to a mutation, that is an alteration in the genetic code resulting in a change in the virus’ protein.

While some of these mutations occurred in all the viral protein components and were often harmless, they were most threatening when they occurred in the spike protein because disease burden increased as the mutation allowed easier entry into cells.

Variants of interest and concern

Mutations occurring in the virus were monitored by genetic sequencing of the viral proteins. Those not highly prevalent or more dangerous were called variants of interest and monitored.

When the viral mutations were shown to be more contagious and caused more severe disease burden they were upgraded from being called variants of interest to being labelled variants of concern (VOC).

These VOCs were first recognized in the U.K., South Africa, Brazil and finally India and were renamed by the WHO with Greek letters Alpha through Delta. The Lambda variant which originated in Peru is not widespread yet in most regions and thus remains a variant of interest.

Why is the Delta variant concerning?

The Delta VOC is now dominating new infections in much of the world and is spreading 50 percent faster than the originally worrisome Alpha variant which itself spread 50 percent faster than the original wild type virus.

Eric Topol, a noted cardiologist and COVID expert has said that the increased risk is due to the virus replicating faster with a shorter incubation period leading to a higher viral load in an infected person.

COVID-19 disease burden relates to the viral load a person is exposed to, which in part explains the greater risk of infection with a VOC that generates higher loads because it replicates faster. Thus the Delta variant is much more transmissible with larger amounts of airborne virus and leads to more super-spreader events and higher numbers of infected people.

So while it is not clear that the Delta variant is much more virulent and deadly by itself, it is more deadly because it creates more cases of disease and thus overall higher numbers of hospitalizations and deaths.

The Delta variant is now dominating new infections in most parts of the world. It is now the cause of over 85 percent of infections in the U.S.

While with the original wild type virus very few young healthy people were being hospitalized or dying, we have now seen a major increase in this population who are no longer relatively safe without vaccination.

The impact of infection on death

As of July 27 The Public Health Agency of Canada reported over 1.4 million cumulative infections and 26,553 deaths.

These deaths represent about 0.1 percent of our overall population or a rate of about 700 per million population. The overall calculated death rate if infected is about 1.9 percent and is heavily skewed to the elderly and those with co-morbidities.

The death rate is likely lower, perhaps 1-1.5 percent since many low grade or sub-clinical infections were not counted especially when testing was not routinely done. While the percentage of the population dying seems low, the deaths that occurred were individual tragedies and more so since so many were preventable deaths.

Hospitalization and ICU care

The disease burden is of course greater than simply the number of deaths.

The hospitalization rate is about 7.5 percent of infections, of which 19 percent of those hospitalized require ICU care and 2.6 percent mechanical ventilation. The age and gender distribution of hospitalized and ICU cases is shown below.

The disease is not benign even for those under 40. This age group accounted for 12.7 percent of hospitalizations and 9.8 percent of ICU admissions. This percentage continues to increase as older people are highly vaccinated and protected and younger people are more vaccine hesitant.

Those that survive are often left with lingering illness and emotional trauma after their brush with death.

Vaccine hesitancy and individual risk

Vaccine hesitancy remains higher in younger people often because they believe their risk of hospitalization and death is very low. The higher viral loads with the Delta VOC have led to more symptomatic and life threatening infections. Anyone hospitalized and fearing ventilation and death typically regret their choice to not be vaccinated.

The low mortality rate should also not be too comforting for the young when you realize the possible misery of being seriously ill, hospitalized and dying badly. The lingering effects of long COVID can also be debilitating. The risks of becoming infected simply put remain much higher than the low risks of vaccination.

Restrictions will ease for the vaccinated and increase for those who choose to remain unvaccinated.

Countries such as Canada, U.K. the U.S. and Israel have very high rates of full vaccination especially in their older population who are thus relatively protected from bad outcomes even from the Delta variant. The disease is becoming primarily a disease of the unvaccinated and those older people whose vaccine immunity is pierced.

After a truly dysfunctional vaccine procurement and roll out, Canada now is at the forefront of rates of full vaccination. Vaccine boosters will soon likely be available to further protect the most vulnerable when the Delta variant increasingly pierces immunity as it is starting to do. We need carefully collected data to inform us when and in whom boosters are required.

The rest of the world is starting to catch up on vaccination rates. According to Our World in Data globally about 4 billion vaccine doses have been administered increasing by 34 million shots daily. We need to continue to help poorer countries by providing vaccines and essential medicines including oxygen.

While the Delta variant likely increases the vaccination levels needed for herd immunity, we are getting closer in Canada. Restrictions will ease for the vaccinated and increase for those who choose to remain unvaccinated.

We need to continue to be vigilant but focus on how to restart life, learn from the hard lessons of what we did wrong, protect jobs and grow our economy. Hardship and restrictions make you value freedom and safety more than ever.

‘They’re gearing up for battle’: Kenney prepares to be Trudeau’s campaign villain


During the 2019 federal election, Conservatives spoke in hushed tones about “the Doug Ford factor” in the campaign. Was the unpopular Ontario premier dragging the federal party down with him?

After the election, the chatter got louder and polling all but verified that Ford had a noticeable negative effect on Conservative chances in a province that was vital to the party’s electoral hopes.

The same poll showed that Alberta Premier Jason Kenney, riding high from an election win, was a strong factor in encouraging people to vote for Andrew Scheer’s federal Conservatives.

In fact, Scheer and Kenney held boisterous joint events, including one at a Calgary baseball diamond where they spoke together from the snow-covered bed of Kenney’s blue pickup truck.

United Conservative Party leader Jason Kenney and Conservative Party leader Andrew Scheer attend a campaign rally in Calgary on April 11, 2019. Jeff McIntosh/The Canadian Press.

To say things have changed in the last two years would be an almighty understatement.

In the wake of the COVID-19 pandemic, Kenney’s approval rating has cut in half, with even Ford polling ahead of him. Scheer has been replaced as Conservative leader by Erin O’Toole and the party has struggled to introduce the new leader to Canadians while the pandemic dominates the news cycle.

The attacks started early on O’Toole and they have ramped up as an election draws near. A recent advertisement by Unifor described O’Toole as another “out of touch politician we can’t afford.”

In a parody of pickup truck commercials, the gravelly-voiced narrator describes O’Toole as “driven to cut health care and public services, just like Jason Kenney.”

If the Unifor ad is anything to go by, Justin Trudeau’s Liberals may be planning to cast Kenney as the next Doug Ford, attacking him as a stand-in for the little-known O’Toole.

Kenney say it’s nothing new for him.

“I’ve already been in that situation, (Trudeau) ran explicitly against me and Alberta in the last election, saying in Quebec in the last week, in French, that we need a prime minister who will stand up to Jason Kenney and the big Alberta oil companies,” said Kenney, in an exclusive interview with The Hub.

“So I certainly hope he doesn’t do that, because I think the role of the prime minister is to strengthen national unity and not drive regional wedges. But he did it before in desperation, I wouldn’t be surprised if he does it again,” said Kenney.

The federal-provincial relationship is, by nature, fractious. The federation always has at least one province that feels hard done by and often it has many.

Along with criticizing the federal equalization program, Kenney has argued that Alberta makes an outsized contribution to the federal budget, compared to what it receives in federal spending. That recurring criticism from provinces actually pre-dates Confederation, with Upper Canadian politicians grousing about their contributions as far back as 1865.

In Alberta, it’s almost a rite of passage for a conservative premier to square off with Ottawa. Former Alberta Premier Ralph Klein spent his provincial career battling the federal government and Peter Lougheed, who presided over the province when Pierre Trudeau brought in the National Energy Program, believed that strong, assertive provinces make for a stronger federation. Kenney appears to agree.

“Trudeau just took it all in with that Cheshire grin.”

Calgary HErald Columnist Don Braid

Kenney said Trudeau’s policy criticisms are fair game and expects to see a lot of that during an election campaign.

“I make the case against his government’s re-election, he has every right to attack my policies, but by running against Alberta’s resource sector, he’s really running against the Canadian national economy,” said Kenney.

“It is obvious to the vast majority of Albertans that this is one of the most hostile federal governments we’ve ever had,” he said.

The campaign may have already started. During a federal announcement in July about funding for Calgary’s Green Line LRT project, Mayor Naheed Nenshi ripped the UCP government for demanding a review of the project, causing delays.

“Trudeau just took it all in with that Cheshire grin,” wrote Calgary Herald columnist Don Braid.

And although there are obvious policy and ideological differences, the phenomenon may simply be driven by the political opportunity created by Kenney’s plummeting approval ratings.

The Liberals will be hoping to pick up one or two seats in Edmonton and may be dreaming of snagging a seat in Calgary.

Mount Royal University political scientist Duane Bratt said the anti-Kenney message could even resonate in one or two urban Calgary ridings.

“They’re gearing up for battle. The difference this time is that the Liberals have chances inside Alberta, which they didn’t in 2019,” said Bratt.

In a June poll, the Angus Reid Institute found that only 31 percent of Albertans approved of Kenney’s job as premier, compared to more than 60 percent after his party won the spring 2019 election.

Politicians at various levels of government are taking notice and scoring easy points by criticizing the Alberta premier. In Calgary, a procession of municipal politicians hoping to succeed Mayor Naheed Nenshi took turns taking shots at Kenney’s government.

In 2019, when Trudeau was targeting Ford, the Ontario premier stayed out of the headlines for the duration of the campaign. Bratt said he doesn’t expect Kenney to hide, in part because it’s personal.

“There has been a pattern of behavior of bad relations on both sides between conservative premiers and Trudeau,” said Bratt. “I think there is a personal animosity between them and it has played out on so many different files over time.”