According to this article in Science, another wave of COVID-19 infections is on the way because several different sub-strains of the Omicron variant have converged on a similar way to evade the antibodies our immune systems manufacture in response to vaccination and/or infection.
It's not possible to say which of the various emerging strains will come to predominate, but one variant, known as BA.2.75.2, is a likely candidate. It is proving to be especially successful at evading antibodies because changes at half a dozen key sites in its genome that affect the way antibodies bind to the spike proteins on the viral coat, mean the antibodies don't bind very successfully.
In a preprint paper posted on the bioRxiv server ahead of peer-review and publication, immunologist Ben Murrell at the Karolinska Institute and his colleagues report that the serum from 18 blood donors in Stockholm, where vaccination and prior infection rates are particularly high, were less that one sixth as effective against BA.2.75.2 than against BA.5. (BA.5 is the currently the dominant sub-strain of the Omicron variant).
AbstractIt's important to note that BA.2.75.2 is not 100% successful at evading the natural antibodies, so it is still essential that boosted vaccination should continue pending an updated version specifically for BA.2.75.2 and similar varianst, since any protection will reduce the severity and duration of infection and reduce pressures on health services.
Several sublineages of omicron have emerged with additional mutations that may afford further antibody evasion. Here, we characterise the sensitivity of emerging omicron sublineages BA.2.75.2, BA.4.6, and BA.2.10.4 to antibody-mediated neutralisation, and identify extensive escape by BA.2.75.2. BA.2.75.2 was resistant to neutralisation by Evusheld (tixagevimab + cilgavimab), but remained sensitive to bebtelovimab. In recent serum samples from blood donors in Stockholm, Sweden, BA.2.75.2 was neutralised, on average, at titers approximately 6.5-times lower than BA.5, making BA.2.75.2 the most neutralisation resistant variant evaluated to date. These data raise concerns that BA.2.75.2 may effectively evade humoral immunity in the population.
Daniel J. Sheward, Changil Kim, Julian Fischbach, Sandra Muschiol, Roy A. Ehling, Niklas K. Björkström, Gunilla B. Karlsson Hedestam, Sai T. Reddy, Jan Albert, Thomas P. Peacock, Ben Murrell
Omicron sublineage BA.2.75.2 exhibits extensive escape from neutralising antibodies
bioRxiv 2022.09.16.508299; doi: 10.1101/2022.09.16.508299
Copyright: © 2022 The authors.
Published by bioRxiv. Open access
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
Just in case any Creationists are tempted to jump on the very low probability of these mutations all arising together as evidence of intelligent design, they are welcome to use it as an argument which makes their creator god look like a hate-fill pestilential monster designing ways to increase the suffering in the world, so I’m hesitant to pre-emptively refute that claim, but the maths are relatively simple.
In addition to cross infection, where two or more strains simultaneously infect the same cell, making a hybrid virus containing mutations from each 'parent' highly likely, even if the chance against these half a dozen mutations arising together in the same viral genome were a trillion to one against, each infected person is quite capable of producing billions or even trillions of new virus particles, especially if they have no natural or acquired immunity, so these trillion to one chances happen multiple times daily.
If this trillion to one mutation happens in a person in a population with a good level of immunity, and is then passed on to a vaccinated or previously infected person, the ability to evade their immunity will give the variant a massive advantage over rival variants, so, probability and natural selection alone are quite sufficient to explain how these variants arise.
And the probability of such a variant arising naturally is massively increased in a population such as that in the USA were there are pockets of vaccine hesitancy due to the pro-Trump antivaxx propaganda of the far right, QAnon, Christian evangelicals, and a Republican Party irretrievably wedded to Trump's panicky response of dismissing the virus as a hoax and not a serious threat.
For some inexplicable reason, though, Creationists would rather we blamed their god for COVID-19 than accept that a natural process is fully capable of explaining it.
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