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Friday, December 9, 2022
Dr. Brown: The race is on, humanity vs. the COVID-19 virus

Dr. William Brown is a professor of neurology at McMaster University and co-founder of the Infohealth series at the Niagara-on-the-Lake Public Library. 


The race is on and it’s by no means certain who is going to win. At this point, the virus seems to be pulling ahead for two main reasons. 

First, the pandemic is now raging out of control in many countries, including Canada, the U.S., U.K. and Brazil, among others. Last year’s late surge was signposted in the new year by record daily death tolls and huge numbers of moderate to severe symptomatic affected patients that threatened to overwhelm health care systems from California to Ontario.

It was the perfect storm: a product in North America of Thanksgiving celebrations, widespread refusals by many to socially distance, wear masks and avoid social gatherings outside of established social bubbles throughout the U.S. election, Christmas holiday celebrations – and something we didn’t count on. 

In the U.K. a highly transmissible variant (B.1.1.7) emerged that within weeks threatened to become the dominant strain in that country and forced PM Boris Johnson to enforce an earlier-than-planned national lockdown.

Within a few more weeks this variant had spread to over 30 other countries, including the U.S. and Canada. It also may have played a role in the burgeoning number of cases in Ontario and forced a lockdown. Had the lockdown been imposed even a week earlier, it might have saved many lives – a brutal lesson hopefully learned. 

Which reinforces the second point: the virus has not been idle. All viruses mutate and this one has had plenty of time and huge numbers, to do so, what with a worldwide playing field, millions and millions of vulnerable humans, and no effective way to keep potentially dangerous variants, such as the U.K. and South African mutants, from crossing borders. 

Mutations are common in nature, the inevitable result of copying errors when in this case, COVID-19’s genome is copied trillions and trillions … and trillions of times.

With so many copies, sooner or later slip-ups occur – perhaps a substitution, deletion or addition of one or more bases or the transposition of chunks of the virus’s genome to other locations in a genome almost 30,000 bases long. Most copying errors are neutral, that is they have no effect on the behavioUr of the virus’s genes and hence proteins and behavioUr. But some confer an advantage on the virus.

That’s what happened with the U.K. mutant. The changes in the genome made the virus roughly 50 per cent more transmissible in a virus that was already easily transmitted, possibly made worse by recent hints that this mutant may be as much as 30 per cent more deadly.

And a mutant strain in South Africa ((501Y.V2) turns out to be even more transmissible compared to the U.K.'s – and like the UK mutant, it also may be more virulent. Yet another mutant recently recognized in Brazil was suspected when some who had had an earlier proven COVID-19 infection, proved susceptible to a second infection, the virus driving the latter apparently having acquired the capability of getting around the antibodies produced in response to the first infection. That's an example of what’s been called “immune escape.”

The latter phenomena is a great concern because it suggests the molecular targets on the virus, which created the initial immune response, might have changed – perhaps a change in the shape or electrical charge of one or more of the spike proteins – which somehow might conceal the target from the body’s immune system.

That could be a real problem for the RNA and DNA vaccines, which were designed to target very specific proteins in the spikes of the coronavirus. If those targets were somehow cloaked by the mutant versions of those spike proteins, some or all of those vaccines might not work or work as well as now. 

And that’s the great concern isn’t it – that this virus might escape one or more of the vaccines in our current crop and that patients who were infected at one time – symptomatic or not – might face a new, novel variant.

If that happened, some vaccines might have to be changed, literally on the run as Moderna a few days ago suggested, to keep up with the mutations by incorporating the mutated version of the RNA in their vaccine.

The same is probably possible for the other vaccines from Pfizer and AstraZeneca and others in the works. So far, fortunately, early evidence suggests those vaccines would be effective against the U.K. variant. But at this time, the jury is out about whether they protect against the South African variant. The companies say yes, but some independent scientists aren’t so sure.

That would be a nightmare – a continuing arms race between emerging viral mutants and virologists to keep vaccines up-to-date – to say nothing about the nightmare of getting the updated vaccines manufactured in high enough volumes and the logistics of getting the vaccines into arms.

And what about clinical trials? They would need to be nimbler than even the stripped-down phase 2 and 3 trials needed to get some of the initial vaccines approved. It all reads like the perfect script for a seasonal horror movie or novel. 

To avoid the looming nightmare there are several steps that need to be taken now. 

1. We need to immunize as many as possible as soon as possible, not only to protect those at risk but to shrink the global playing field for the virus.

2. Think globally, after all this is a global problem and won’t be solved within national boundaries any more than climate change will be.

3. The public must understand the nature and magnitude of the challenge – yet many for political, cultural or religious reasons (or in some cases wilful ignorance), treat standard health care measures such as wearing proper masks, distancing and avoiding groups unless they’re in their bubble, as optional rather than obligations to the community. Far from optional, those simple measures work and must continue by all – vaccinated and unvaccinated. That obligation to protect others will continue probably well beyond vaccinating 70 to 80 per cent of the population because until the virus is effectively corralled worldwide, mutants may arise, spread and cause renewed surges, possibly necessitating updated vaccines.

4. Do what the British have done from the outset and continue to do so well: sequence the virus’s genome in roughly 10 per cent of all positive cases compared to less than one per cent in the U.S. and fewer still in Canada. Without regular sequencing of the genome of the virus, virologists, pharmaceutical companies, health care planners and governments are flying blind in managing the pandemic and keeping vaccines up to date. We must have real-time intelligence on potentially worrying changes in this virus’s genome from around the world and freely share what’s learned with others. Remember, this virus knows no borders.

5. Governments at all levels need to be far more forthcoming with their goals and strategies. They must respect and treat the public as essential allies, as indeed they are. Information shared with the public should be as clear as possible without in any way dumbing down the message. That’s always been a real problem with science in general and health care experts who aren’t used to clearly communicating publicly what they know or question. One way for them to do so is to assume that the public is as intelligent as the messengers, even if not so familiar with the language of the experts. Drafting opaque government standard-issue documents is not helpful. 

The next few months will test whether we, our health care system and federal, provincial and local leaders, are up to the interdependent challenges of vaccinating everyone, caring for those who are ill (whether from COVID-19 or other health problems) and helping those who face social and economic challenges.

This must happen while doing our level best to keep up with a changing virus and acting accordingly. In past times, other generations faced equally daunting challenges and proved they were up to the job. Will we?