Sunday, August 15, 2021

Vaccines and variants

by George J. Dance

When in comes to Covid, a lot can change in a month. In the U.S. the UK, and Canada, the pandemic appeared to be finally over by the beginning of July: cases and deaths were dropping back to last summer's low levels, while growing levels of vaccination seemed to indicate they would stay that way. Now Covid is resurgent, with cases and deaths rebounding in all three countries, and indications that the vaccinated, too, are now spreading it

What happened? A few brave souls question whether vaccine effectiveness may be waning; but the majority consensus puts the blame on the Delta variant, now the dominant coronavirus strain throughout the world. But what caused that variant? Where did it come from? Most importantly, for some, whom do we blame for it? 

By this point it has become standard to blame the unvaccinated for the entire pandemic, and the Delta variant is no exception. “Unvaccinated people are potential variant factories,” William Schaffner (a professor of infectious diseases at Vanderbilt University Medical Center) told CNN in July – a claim that CNN shortened in its headline to the punchier "Unvaccinated people are ‘variant factories". In that punchier form, the meme was headlined widely in both mainstream and social media. Some, like Canada's Global News, went so far as to claim that merely being unvaccinated makes a person "a risk" to others: "'Variant factory’: The unvaccinated pose a risk to more than just themselves.".  

Yet going beyond the headlines told a different story. The Global article, for example, quoted Winnipeg epidemiologist Cynthia Carr, whose message was different:

"It’s a good, succinct term that I hope catches people’s attention: ‘variant factory,'" Cynthia Carr tells 680 CJOB.
What is that?
Carr says it could be the body of anyone who gets COVID-19.
"The virus cannot live and thrive outside of a living cell – it needs that cell to survive." 

Note that: A "variant factory" can be any living person infected with Covid. Even double-vaccinated people can be infected with Covid, since some double-vaccinated people have clearly died with it. Every living person, vaccinated or not, infected or not, is a "potential variant factory," including those who like to throw the term around so much.

If not the unvaccinated, who or what is responsible for the variants? Could it be the vaccination program itself? That theory is becoming popular in some alternative media and social media, including the expected fever swamps where bizarre conspiracy theories breed. That is no reason to reject the theory, but it is reason to dismiss those accounts and look for a more credible source. 

Back in May, GDPA found and blogged what looks like the original source of the claim, a video interview (in French) with the 2008 Nobel Prize winner (yes, in Medicine), Luc Montagnier. In the account we blogged, Montagnier was quoted as saying "that 'it is the vaccination that is creating the variants',... 'There are antibodies, created by the vaccine' that force the virus to 'find another solution' or die. This is where the variants are created. It is the variants that 'are a production and result from the vaccination.'" 

I can read French, with difficulty, but there is no way I can follow a spoken video. So I had to turn to my own limited knowledge of viruses, most of which I have picked up only this year, to try to piece out out an explanation on my own.

Because it has no DNA, a virus is not genetically stable; it reproduces by copying its own RNA, and in the process numerous 'copying errors' can happen. Those last give rise to mutations. Most mutations are suboptimal compared with the original strain, and quickly die out. Occasionally, though, a mutation can confer an advantage on the new strain: for example, it may incubate in a shorter time, meaning it can reproduce faster than antibodies can eliminate it. (The Delta variant is said to incubate in four days, versus six for the original strain.) In that case the mutation can survive and even thrive in an infected person, and may even displace the original strain (though that last is unlikely, given the original strain's head start). 

When someone infected with a new mutation (A) infects an unvaccinated person (B), then both the original strain and mutation can be passed on. Given that the original strain is more likely to be dominant, it is more likely to be the one passed on, though of course it is logically possible for an unvaccinated person B to catch both. 

If person B is vaccinated, though, there are three possibilities. Every vaccine has an efficacy of more than 0% and less than 100%; meaning that it will suppress some (in fact, most) infections, but fail to suppress others. Person B's vaccine may suppress both strains, fail to suppress both strains, or suppress only one. In that third case above, the vaccine will be suppressing the less infectious original strain, meaning that person B gets infected only by the more infectious mutation. If person B goes on to infect persons C, D, and E, they will also be infected by the new mutation. 

The result over time will be a growing number of people spreading a new, more infectious strain of the virus through the community. Since the new strain incubates faster, and more people are susceptible to it, it will spread faster than the original strain, will infect more people, and can even become dominant in the community. At that point the mutation has become a variant. Vaccination has not produced the new variant – random mutation did that – but by suppressing its less infectious competition, vaccination has selected for the new variant.

That was my theory, which I dubbed "artificial selection". However, as I have noted, I am no scientist, and my reading in the field is limited. So how to test my own assumptions? Who better than a scientist challenging Montagier's theory? Fortunately, I was able to find one of those: Peter Stoilov, PhD, an associate professor of biochemistry who leads the variant sequencing efforts in West Virginia, and who describes Montagnier’s theory as 'completely bonkers.'         

Here is Dr. Stoilov's lengthy debunking, from an interview with the website healthline.com:

"The fact on which he bases his argument is that mutations can change epitopes that the immune system has learned from the vaccination, and this gives some selective advantage to the virus. Consequently, in his mind, this would ‘create’ new, more dangerous variants," he said.
However, Stoilov pointed out that "selection does not cause new variants to emerge; it merely selects some of them."
"Mutations and variants occur randomly and independently of vaccination or any other selection process. In fact, they may precede selection by years or millennia," Stoilov said....
Stoilov said it’s a well-established fact that selection does not cause mutations.
"The facts that Dr. Montagnier ignores are that, while vaccination may select for some variants, it is still effective at suppressing them and the overall effect is a dramatic reduction of infections and a milder disease when the virus manages to break through the vaccine," he said....
If vaccines were creating new dangerous variants, then Stoilov said we would see proportionately more new variants emerging over time among vaccinated populations than with unvaccinated parts of the world.
There would also be a lot more diversity among the virus variants in countries with high vaccination rates, and increased disease spread and mortality among vaccinated people.
"We see nothing of that. In fact, we see exactly the opposite," Stoilov said. "In places with high vaccination rates, the case numbers and mortality are dropping; virus diversity is limited to few (one to three) variants; and, so far, no new variants are emerging among vaccinated populations." 

Stoilov does a good job rebutting the idea that the vaccine is causing the mutations that become variants. But his arguments do nothing to refute the theory that mass vaccination is selecting for them. Rather, he freely admits that "vaccines may select for some variants" (while pointing out that this "selection does not cause new variants to emerge; it merely selects some of them") – which is exactly what I had already concluded. 

None of the above is a reason to stop vaccination, as Montagnier is suppose to have urged. So far, vaccination has been effective at reducing cases, hospitalizations, and deaths; on these terms, mass Covid vaccination has been a success. Artificial selection is merely an unintended consequence of that success: precisely by stopping most (but not all) infections, vaccination selects for more infectious variants. If the result is less, not more, severe injury or death – and so far that is the case – then vaccination has to be seen as an unalloyed good. 

So no policy changes follow from adoption of the artificial selection hypothesis. All that follows is increased awareness that in epidemiology, as in every other field of human action, policy changes will have unintended consequences, of which the policy makers are unaware and unable to anticipate beforehand, much less adequately explain or deal with afterwards. 

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