What are the new variants of COVID-19 and how are they produced?
The genetic mutation in viruses (and therefore the emergence of new strains and variants) is something totally expected from a scientific point of view.
As viruses are transmitted and passed from one person (or living being) to another, their genome undergoes small changes that are part of their natural life cycle.
In addition, the appearance of medical treatments and vaccines causes viruses to suffer a very high evolutionary pressure which, in turn, accelerates the appearance of new strains that escape said treatments and vaccines in order to continue its spread.
Some of these variants appear and disappear without leaving a trace, while others persist over time.
In the case of COVID-19, the so-called “strains” are actually “variants”, since they have not accumulated a significant number of mutations that cause a significant transformation of the virus biology. 3 variants of SARS-CoV-2 have been detected worldwide:
- British: In the UK, a new variant called VUI 202012/1 – also referred to as lineage B.1.1.7 – has emerged with an unusually large number of mutations. This variant spreads more easily and quickly than other variants with an increase in transmissibility of between 50% and 70%. Currently, there is no clear evidence that it causes a more serious disease. This variant was first detected in September 2020 in the south-east of England. Since then it has been found in numerous countries around the world, a total of 70 including Spain.
- South African: In South Africa, in early October 2020, another variant called 501.v2 – or lineage B.1.351 – was detected that is independent of the UK variant, but with which it shares certain mutations. It has been found in 32 countries, Spain just recently discovered its first case on February 2021.
- Amazonian: In Brazil, a variant called P.1.- or lineage B.1.1.28 has also emerged- This was identified in four travelers from Brazil who were evaluated during the routine check at the Haneda airport on the outskirts of Tokyo , Japan. The Brazilian variant contains a set of additional mutations that can affect the ability to be recognized by antibodies. It has been detected in 8 countries, Spain is not among them.
How is the virus detected in patient mucosa samples?
As we all know, the most effective test used to detect the COVID-19 virus is PCR (Polymerase Chain Reaction).
With a swab, a sample of the mucosa of the patient’s nose is removed and analyzed by experts in the laboratory in search of the genetic material of the virus (in this case RNA).
Specifically, the test we perform at Life Length detects 3 specific regions of the coronavirus genome: protein S (spike), protein N (nucleocapsid) and ORF1 ab. In the presence of these regions in the sample taken (and, therefore, in the presence of the virus), its massive replication occurs in the laboratory, which allows the identification of SARS-CoV-2, commonly known as COVID-19.
Does our PCR detect the British variant?
Precisely, the UK variant (the one that is causing the most damage right now worldwide) was detected because scientists obtained positive PCR results in samples with two of the gene regions present and a third negative not present.
This led them to consider that there was a new strain that had managed to mutate, which has been corroborated in a subsequent genetic study in which 16 more new mutations have been found in this UK variant (in addition to the spike mutation).
On the other hand, it has been found that the South African variant, although different from the British one, shares with it having mutations in spike.
In other words, the PCR that detects 3 specific regions of the genome, can indentify these 2 variants. At Life Length, we can detect them for everyone’s peace of mind and without a doubt with our PCR tests, so we will not obtain false negative results in these cases.
What about the vaccines?
It seems that the vaccines that we have on the market as February 2021 are still valid for these new variants, Moderna and Pfizer assure it, although they have verified that their vaccines are more effective against the British variant than against the South African, in which the vacines causes a lower neutralization of the virus.
In the event that the SARS-CoV-2 genetic mutations become very high or in regions that cause very drastic changes, we may be facing cases in which current vaccines do not work and new ones more specific to these variants have to be created.
All this situation is something normal that already happens in other viruses such as the flu (influenza), for which children, the elderly and people at risk are vaccinated every year in Spain.
In short, COVID-19 is going to be present in our lives for the moment, so we must follow the health recommendations and take tests if we have doubts about having been in contact with the virus or having symptoms.
- European Centre for Disease Detection and Control. (2020). Rapid increase of a SARS-CoV-2 variant with multiple spike protein mutations observed in the United Kingdom.
- Applied Biosystems, Thermo Físher Scientific. (2020). Impact of the 69-70del mutation in the spike protein of SARS-CoV-2 on TaqPath COVID-19 testing assays.
- Applied Biosystems, Thermo Físher Scientific. (2020). Emerging mutations in SARS-CoV-2