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According to experts, the British strain of coronavirus may already dominate in Lithuania, however a professor and immunologist at the VU Center for Life Sciences says that one should not be surprised that one strain of the virus displaces another.
Although there are doubts as to whether the available vaccines will be effective enough against the varieties that spread, A. Žvirblienė notes that it is too early to talk about it. Data on the increased mortality of new variants of the virus are also lacking.
Still, a new advance in the treatment of the disease caused by this insidious virus is expected from the development of biopharmaceutical antibodies, which were also used by former US leader Donald Trump, who fell ill with COVID-19.
A conversation with the entire immunological scientist A. Žvirblienė about all this.
How many coronavirus mutations have already occurred and which of the strains is currently the most concerning?
The number of mutations can hardly be named, because in each of these variants of the virus – the so-called British, South African, Brazilian or Japanese – there has not been a single mutation, but a whole series of mutations. Consequently, these variants are named and include mutations that occur in the needle protein, although they are present in other parts of the genome. The virus evolution process is ongoing and those variants are changing. The new variants, if they are more virus-friendly, displace the existing ones.
What is known at this time is whether these varieties are more contagious and dangerous.
As for the British version, there is already enough scientific data to confirm that it is spreading faster. Although those percentages are still adjusting and range from 40 to 90 percent, there is no question that this variety is spreading faster than previous variants. Due to the mortality and more serious complications of the disease, again, the data is conflicting, it is not clear how accurate they are, because they were carried out with a small number of people. British studies suggest that mortality may be higher, but more research data should be awaited. So it is too early to talk about it.
What is most concerning about the South African variant is that the vaccine may not work as effectively against it, and there is still a risk of becoming infected with older variants of the virus. Regarding the spread of this variety, the data is not very clear, but it also seems that it is spreading faster. On the other hand, even if it did not spread faster, it is clear that if vaccines and the transmission of another variant of the virus provide less protection against the South African strain, this would reduce the effectiveness of the measures used.
Some mutations in the Brazilian and Japanese variants are the same as those in the South African strains, and the data is still being refined due to their higher infectivity. Basically, to the extent that I was interested in all of these varieties, I didn’t see any clear evidence that they increased the risk of more serious diseases or mortality. There are all kinds of interpretations, but it would still be difficult to say which is greater. On the other hand, if the spread of the strain is faster, there will naturally be more illnesses and more deaths. It is simple arithmetic.
Vaccine manufacturers are in a rush to compare which vaccines are most effective against strains. Are any of them really superior?
Real-world data suggests that current vaccines are quite effective at protecting against the British variant. As demonstrated by the vaccines Pfizer and AstraZeneca, J. In Great Britain, they were effective enough to stop the spread of the British variety.
The South African variant is not widespread and there is not much real world data yet. There are some experimental data, but these are indirect, in vitro investigate. After all, many more different elements are activated in the immune system of the vaccinated person. And all the more so since each manufacturer performs this type of test with different models, which makes it difficult to compare results.
One of the vaccines that has been shown to respond quite well to the South African variant is the recently registered Johnson & Johnson vaccine. And those data are due to the fact that the phase III clinical trials were conducted specifically in PAR and the United States. Overall, therefore, the data remain inconsistent and insufficient, and more information is needed on the efficacy of vaccines.
It seems that the strains of the virus that you will have to deal with are a kind of lottery. Are there ways to fight the virus other than vaccines?
The arsenal of weapons with the virus also includes biopharmaceutical antibodies that are being developed through pharmaceutical campaigns. They work in a similar way to plasma from people with COVID-19, but are more accurate. They are specifically designed to neutralize and inactivate the virus. It is not used that much yet, but it is still a weapon.
These antibodies are directed against a particular sequence of the viral protein S, there is no way that a single antibody will recognize the entire protein. A particular antibody recognizes a very small portion of a viral protein, which can be only a few amino acids. That is, if a mutation in the virus enters a recognizable part of the antibody, called an epitope, in which case the effectiveness of the antibody disappears completely and it is no longer capable of neutralizing the virus. Here is a threat that those new variants of the virus could become insurmountable with the newly developed antibodies.
How are these antibodies made?
These are artificially created antibodies, and otherwise the antibodies are usually produced by the human body after the vaccine has been vaccinated or relapsed. Antibodies are the result of the activity of the immune system. We have billions of different antibodies that attack viruses. They circulate in the blood and therefore contain a mixture of various antibodies in the plasma of individuals infected with COVID-19.
Biopharmaceutical antibodies, because they are created artificially, are directed against a very specific sequence of the virus. And those sequences are selected so that the antibody blocks the virus from entering the cell. Because there is no point in creating antibodies that would otherwise bind to the virus. Therefore, they are designed to recognize a particular protein S sequence that is involved in introducing the virus into the cell, so that they can stop the spread of the virus.
In general, the field where potentially dangerous mutations occur in the virus is not very wide. But the bottom line is that the neutralizing antibodies also target the same “area” of the virus. The same is true of antibodies from relapsed or vaccinated people, as they deliberately stop the spread of the virus by attacking those specific parts of the cell.
So these antibodies are basically used as a treatment? How widely is it applied?
Thus, for example, when the former president of the United States, Donald Trump, fell ill, he was also treated with experimental biopharmaceutical antibodies, not yet registered, and received a “cocktail” of two antibodies.
At present, several of these antibodies have been developed in the world and some have already been registered. But they are still developing intensively because it is not a vaccine, it is a way of treating an already infected person. When a person is already sick, the injection of these antibodies prevents the virus from multiplying, which protects healthy cells from the virus. They are usually used early in the infection until the virus has spread widely. However, so far they are not used much as it is quite an expensive treatment, and there is still a real threat that they will no longer work if the virus changes.
It is one of the weapons against the virus and a lot of effort is being put into its development, new technologies are being developed. After all, it is not only prevention that is important, we must also think about those who are sick and how to protect them from serious diseases.
Looking ahead, can we expect the dominant strain of the virus to always be different?
Yes, as I mentioned, it is a natural process of evolution. We saw it best early last summer, when the virus first spread from China, an easier-spreading variant later appeared in Europe, displacing the original. Thus, even in early summer, the Spanish version instead of the Chinese dominated in Lithuania. So even now we are observing the natural process of evolution of the virus that is taking place in other countries as well.
Could the virus become less contagious or “enraged”?
The virus is unlikely to become less contagious because it is unfavorable to you. This, unfortunately, I am afraid to send an optimistic message here. Because normally the evolution of the virus takes place in such a direction that the less contagious variants are supplanted by a better spread.
As for mortality, it is not very good for the virus to kill its host, but it can happen by accident, because there are various mutations and they can change the biology of the virus in such a way that it will be more dangerous. But again, it’s too early to talk about it.
In any case, it is very good that we are finally having the complete genome of the virus, and we see that this is important. You just have to realize that these are complex studies. Here’s a sample taken on March 2, where a South African strain was found, tested just a few days ago. This raises the question of whether it will be possible to isolate the spread of varieties in time. Because without quarantine, hardening, the new strain of the virus would already be widespread.
Thanks for the conversation.
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