Is Sars-CoV-2 already targeting the vaccinated?

Will future variants of Sars-Cov-2 tailor themselves to target the vaccinated?  Given that up to 90% of the population of some countries are now fully vaccinated, the question should perhaps be: Why would Sars-CoV-2 NOT target the vaccinated? 

Selective pressure on the virus may mean an increasing drift towards variants that can overcome vaccines, as we are already seeing with Omicron.

There is some evidence in the scientific literature that the global vaccination campaign may have, through selective pressure, encouraged the virus to target the vaccinated.

  • In this Medrxiv preprint, “COVID-19 vaccines dampen genomic diversity of SARS-CoV-2: Unvaccinated patients exhibit more antigenic mutational variance”, the authors state that “This study presents the first known evidence that COVID-19 vaccines are fundamentally restricting the evolutionary and antigenic escape pathways accessible to SARS-CoV-2.”
  • In this PLOS paper, the authors assert that there is a “risk of rapid evolutionary escape from biomedical interventions targeting evolution”, and “predicted resistance timelines are comparable to those of the decay kinetics of nAbs raised against vaccinal or natural antigens, raising a second potential mechanism for loss of immunity in the population.”
  • In this paper, “Implication of SARS-CoV-2 Immune Escape Spike Variants on Secondary and Vaccine Breakthrough Infections”, the authors state: “The increasing degree of immunity in the human population is inevitably conferring a great deal of selective pressure on the virus that promotes the rise of antibody escape mutants. The emergence of immune escape mutants is perhaps most apparent in chronic COVID-19 patients as documented in multiple reports.”
  • This UK government paper suggested ways in which Sars-CoV-2 may evolve in future: “Antigenic ‘shift’: Natural recombination events that insert a different spike gene sequence (or partial sequence) from human CoVs MERS-CoV… This would recombine into the ‘body’ of SARS-CoV-2 that is capable of high replication in human cells. The consequence could be a virus that causes disease at a level similar to COVID-19 when it first emerged but against which our current battery of spike glycoprotein-based vaccines would not work.
  • In this Virolyvj paper, the authors say “we speculate that with continued circulation, vaccination and convalescent sera therapy, further positively selected for mutations in the NTD are likely to occur.”


Shown below, there certainly seems to be a bias towards infecting the vaccinated in the daily case figures from Denmark’s SSI. Double and triple vaccinated individuals were making up ~90% of all new daily cases recently.

Shown above, from the latest Danish report for vaccine breakthrough infections, it is clear that the vaccinated make up far more of new Covid cases than the unvaccinated.

Shown below, nearly 300,000 cases of Covid are vaccine breakthroughs for those with two doses, and nearly 35,000 cases are breakthrough cases for those with three doses.


Clearly, Sars-CoV-2 will become under ever greater selective pressure to infect the vaccinated as the pool of unvaccinated people decreases.  Deliberately targeting the vaccinated cohort may be the only possible way for the virus to survive in future.

You may not feel comfortable with the issues this post deals with, but if you haven’t considered the key question in this post – Could Sars-CoV-2 start targeting the vaccinated? –  then you simply haven’t been paying attention for the last two years.

Selective pressure forcing Sars-CoV-2 to target the vaccinated is not only a possibility, with the Omicron variant, it may have already started.


Denmark: ~90% of Omicron cases are double or triple vaccinated *17 UPDATES*

Deltacron: a new variant that combines Omicron and Delta discovered in Cyprus *4 UPDATES*

Cypriot authorities have reported the detection of up to 25 cases of infection [now 77 cases – see updates] with a combined version of the Delta and Omicron variants of the SARS-CoV-2 coronavirus which they have named “Deltacron”.

“Currently there are coinfections of Omicron and Delta. We have found a variant that is a combination of both,” explained Leondios Kostrikis, professor of Biology at the University of Cyprus and director of the Laboratory of Biotechnology and Molecular Virology.

Kostrikis and his team have highlighted that they are more frequent in hospitalized patients for COVID-19 than in non-hospitalized positives. “We will see in the future if this variant is more pathological or contagious or if it will be imposed” on Delta and Omicron, he has indicated, although in his opinion it is most likely that it will be overshadowed by the Omicron variant as it is more contagious.

El Periodico report


UPDATE 1 – 8th January 2022

“Dr Leontios Kostrikis, who leads the team of scientists working at the University of Cyprus’ biotechnology and molecular virology lab, said a new coronavirus variant has been identified in the community.

Speaking to local media, Kostrikis explained that the new variant, which has been dubbed Deltacron, shares the genetic background of the Delta variant along with some of the mutations of Omicron.

“We have found a significant number of mutations only previously found in Omicron cases, which is different from other variants as it has 30 mutations,” he said. “Ten of these were identified in these samples taken in Cyprus”. report

UPDATE 2 – 9th January 2022

UPDATE 3 – 9th January 2022

Cypriot Scientist Says Covid-19 Variant Deltacron Not an Error

Bloomberg report

UPDATE 4 – 9th January 2022

Speaking to local media, Kostrikis explained that the new variant, which has been dubbed Deltacron, shares the genetic background of the Delta variant along with some of the mutations of Omicron.

“They do not know the results we have,” he told Sigmalive.

He said that in addition to the initial 25 individuals found in Cyprus they had found another 52.

Cyprus-Mail report


Image by PublicDomainPictures from Pixabay