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Dangerous Original Antigenic Sin Anticipated in SARS-CoV-2

Disclaimer : This is an opinion and a prediction that includes as many sources and the best logic possible. Do not base your personal health decisions on it. Plain Language Introduction SARS-CoV-2 is a novel virus with its closest relatives in bats, emerging in the human population at some point in late 2019. As a newly introduced pathogen, there was only one variant at first. Now we have thousands of strains that have been identified, with countless individual virus particles with countless mutations. The genetic diversity of SARS-CoV-2 is much greater than scientists thought it would be by this point in time. Recombination and Evolution That's because we failed to notice that SARS-CoV-2 relies heavily on recombination for evolution. With recombination, in a host that is infected with two strains of the virus, the virus can effectively create a child from two parent virions(a virion is a single virus) through a process called strand switching. When creating a new vi
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Booster Shots Already: Why?

There are five fascinating things about our choice to use booster shots. I will try to explain each, but unfortunately, some introduction is necessary first. COVID Vaccines: How Good are They Really? Global governments have bet the farm on vaccination eradicating (remember when we used to talk about "herd immunity"?) or greatly prolonging the emergence of SARS-CoV-2 as a widespread pathogen to such a great extent that they're deploying vaccine passports for routine, daily activities , demonstrably not a great idea almost regardless what you want to achieve. It was immediately apparent that SARS-CoV-2 was very contagious. Later studies found it to have had a base initial R0 of around 5.7, compared to around 1.3 for the average influenza strain. That meant that achieving an effective vaccine was always going to be extremely hard: a 40% effective flu vaccine could bring Reff close to or below 1, but a 40% effective SARS-CoV-2 vaccine would come nowhere close. The
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Do Vaccines Prevent COVID-19, or just Delay It?

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First, the good news: it looks like global Reff for SARS-CoV-2 is approaching 1 . However, what lies next? Do we see sharp case declines like India and Indonesia did after Delta passed, will we see a lingering high level of cases like South Africa , or something else entirely? Second, the bad news: it's unlikely to stay at or below 1 for long. That could always have been anticipated due to the high R0 and evolutionary rates of SARS-CoV-2 . https://origin-coronavirus.jhu.edu/data/new-cases Unlike India and Indonesia, heavily vaccinated countries like the UK are demonstrating protracted Delta waves, which raises independent questions about whether vaccination prevents cases or just delays them. The US is as well. Still, Reff is trending towards 1 here, albeit at a very high level of cases. We can expect it to hover there as it moves north with the changing seasons. A brand new letter to the editor in the NEJM depicts this perfectly. You will see that infection h
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Is South Africa our Preview of Global Case Trends?

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As SAGE implied in their 20th Technical Update's note 1.8.1 , we have effectively multiple serotypes of SARS-CoV-2 already, as Delta antisera doesn't neutralize B.1.351 nor B.1.621 virus meaningfully. That makes South Africa a potentially interesting case, because B.1.351 and C.1.2 emerged there. B.1.621 emerged in Colombia and has accounted for a significant percentage of cases, but Delta caused a serious wave in only South Africa. Beta was never recorded in Colombia and Delta barely touched them, and interestingly, they are now far below their record high infections, indicating that B.1.621 antisera is effective against its respective virus. https://origin-coronavirus.jhu.edu/region/colombia The lack of Delta's emergence could be geographic and political, but it may also mean that B.1.621 antisera is effective against Delta, which would be very encouraging news. https://outbreak.info/situation-reports?pango=B.1.621&selected=COL&loc=IND&loc=ZAF&
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Possible ADE or OAS Showing in COVID-19?

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Vaccinated people infected by Delta are more likely to be hospitalized than unvaccinated people by Alpha. The statistical power of this study isn't great, but it implies that vaccinated people are more likely to need hospitalization. Ware the confounders. https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(21)00475-8/fulltext Reading the full paper, we find 1.9% of unvaccinated Alpha infectees required hospital admission. 2.2% of unvaccinated versus 2.3% of vaccinated Delta infectees required it, and 3.4% of vaccinated Alpha infectees required it. Thus, strangely, vaccination appears in these findings to increase the risk of hospitalization or emergency treatment required. The statistical power of these findings isn't very great because of too few hospital admissions amongst vaccinated infectees, and bear in mind we vaccinated people at higher underlying risk first and more thoroughly and the propensity of people who have been vaccinated to also be more l
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Original Antigenic Sin, Antibody-Dependent Enhancement, and COVID-19's Future

Original antigenic sin(OAS) has not yet been demonstrated in SARS-CoV-2 . However, I strongly believe that OAS will manifest itself, and it will be a bad and worsening problem over time. If I am correct, it may mean that getting vaccinated will become actively dangerous, depending on antibody-dependent enhancement(ADE) and its degree. OAS occurs when an immune response is produced by the body to a closely related pathogen or vaccine(such as a different strain of a virus) instead of generation of a novel immune response . This is because of homology between the two intruders' epitopes and resulting cross-reactive immune activity. SARS-CoV-2 has clearly demonstrated induction of variably cross-reactive antibodies with strain-variable neutralization potential. It has been demonstrated in many viruses ranging from Dengue Fever to influenza to HIV-1 . The set of viruses is not arbitrary: OAS abuse is a particularly effective strategy in viruses that mutate quickly, like influe
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What does Vaccine Efficacy Really Mean and How Might it Change?

Summary: The "efficacy" of a vaccine(VE) is a convenient number, but it's often provided without vital context that would ensure it is interpreted correctly. There are different kinds of efficacy that matter, and the numbers reported are often at peak levels following vaccination. It is in the commercial, professional, and political interest of drugmakers, the media, virologists, and policymakers to emphasize the highest number to demonstrate the power of the vaccines. The 3 primary outcomes that vaccination is intended to prevent are severe disease, infection, and transmission. The number for severe disease is likely to be highest, while the number for transmission is likely to be lowest. This is because different aspects of the immune response affect each. There are 3 main takeaways: VE is usually reported in terms of prevention of severe disease, VE can change against infection and severe disease independently, and SARS-CoV-2 is likely to escape from today
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