A micron variant of the coronavirus is “a kind of Frankenstein”, in the words of the virologist Inmaculada Casas. It presents more than half a hundred mutations, 36 of them concentrated in the spike, to a protein that it uses as a key-master to invade human cells.
The antibodies —the human defenses generated by a vaccine or by a previous infection— know how to recognize the original coronavirus spike from Wuhan and annul it. The great fear is that the numerous mutations in the spicule give microns misleading antibodies, reducing the effectiveness of the vaccines. A preliminary study by the University of Stellenbosch (South Africa) suggests that, compared to previous variants, such as delta (dominant non-planet axis), they have microns or three times the ability to reinfect people who have covid-19.
You anticorpos we can not reconfirm bem o mutated virus
You anticorpos we can not reconfirm bem or mutated virus
You anticorpos we can not reconfirm bem o mutated virus
Some mutations of the micron, albeit disso, alter its way of coupling to the receptors of human cells, according to the bioinformatic models of the virologist Javier Jaimes. The effects of this novelty are still an enigma. An international team of scientists coordinated by the National Institute for Infectious Diseases in South Africa calculated on the sixth-fair that omicron is expected to be twice as fast as delta. The explanation could be a greater transmissibility, due to its better ability to penetrate human cells, or a greater ability to dribble antibodies and reinfect. Oh both.
O encaixe da ômicron nas human cells is different. his mutated form I could facilitate your entry.
O encaixe da ômicron nas human cells is different. his mutated form I could facilitate your entry.
O encaixe da ômicron nas human cells is different. his mutated form I could facilitate your entry.
The micron fit in human cells is different. his mutated form I could facilitate your entry.
The unprecedented accumulation of mutations in the micron variant could completely change the behavior of the virus. Oh no. Virologist Sonia Zúñiga recalls that “in biology 1 more than 1 is always equal to 2”.
Weeks will pass, or days in the best hypotheses, until the scientists get a real portrait of the micron variant. Some researchers, meanwhile, have started to make conjectures based on the few data available in South Africa. The biologist Tom Wenseleers, from the University of Leuven (Belgium), calculates that each infected pela ômicron would be contagious in more than eight pessoas numa população non-immunized population, compared to 2.5 of the original virus from Wuhan and 6.5 of delta, to variant more transmissível até agora. Wenseleers also credits that the ômicron’s ability to reinfect can be up to five times greater than in previous versions. These results still need to be viewed with care, but two leading specialists in the new coronavirus, or Danish biologist Kristian Andersen, believe that the reality should not be much different.
A ômicron is um frankenstein because it brings together dozens of advantageous mutations for the virus and is seen separately in the four worst previous variants, as identified in India, Brazil, the United Kingdom and South Africa in 2020. The real effects of the combination of the 36 mutations in their spike are still a mystery .
mutations
ACE2 receptor gives
human cell
virus spike
mutated (ômicron)
Source: GISAID and CoVariants.
As mutations Q498R, N501Y and S477N Increased affinity of viruses for ACE2 receptors give cells
Mutations associated with a possibility greater ability to escape two antibodies: G339D, S371L, S373P, S375F, K417N, G446S and E484A.
Viruses need to cut the spicule to initiate cell invasion. As mutações H655Y, N679K e P681H, localized not localized by furin cutting, we could facilitate the process.
The SARS-CoV-2 coronavirus is basically a message of 30,000 letters, with instructions to hijack a human cell and make thousands of copies of itself. Each of these letters is simply the initial of a chemical compound with different amounts of carbon, hydrogen, nitrogen and oxygen. There are four types: adenine (C₅H₅N₅), cytosine (C₄H₅N₃O), guanine (C₅H₅N₅O), and uracil (C₄H₄N₂O₂). This brief chemical text já matou more than five thousand people. Since its appearance at the end of 2019, the coronavirus has multiplied several times four times, committing typing errorsexchanging one letter for another, which sometimes are advantageous, just by chance.
Assim produced a mutation
Or a virus hijacks a human cell to make thousands of copies of itself.
The cellular machinery uses 30,000 letters and for each three of them it manufactures an amino acid, the essential unit of the virus.
No copy process error. A micron accumulates 36 mutations in its spicule, which could facilitate cell invasion.
Assim produced a mutation
Or a virus hijacks a human cell to make thousands of copies of itself.
The cellular machinery uses 30,000 letters and for each three of them it manufactures an amino acid, the essential unit of the virus.
No copy process error. A micron accumulates 36 mutations in its spicule, which could facilitate cell invasion.
The virologist Theodora Hatziioannou believes that ômicron will be semi-duvid “the most resistant variant” to human defenses. Her team at the Rockefeller University, in New York, modified in September a harmless virus of gado, increasing-lhe a spike of the coronavirus with 20 mutations, many of them also present now in the micron. Their artificial virus was able to completely escape the antibodies generated by a previous infection by covid-19 and also produced by two doses of an RNA vaccine, such as that of Pfizer and Moderna. “A ômicron will be very resistant to neutralizing antibodies. We could make this forecast with a lot of confidence thanks to our synthetic spicule”, warns Hatziioannou.
As human defenses, meanwhile, are a powerful army not that the anticorps are just a battalion. Vaccines and previous infections by coronavirus induce, for example, the formation of T lymphocytes, white blood cells that annihilate infected cells. Hatziioannou hopes that the vaccines will continue to prevent the majority of two serious cases of covid-19 and the deaths, as of now, but it is necessary to wait to confirm this. “Logo we will see”, he says to the researcher.
Microbiologist Patricia Muñoz leads a team that identified the first case of micron in Spain, or a 51-year-old man, vaccinated with two doses from Pfizer, who arrived in Madrid from South Africa on November 28, with symptoms of poor importance. The dozens of cases currently being seen in Europe are not serious. “This variant could replace delta, which is absolutely possible, but the vaccines are causing the micron disease to be mild. We are more prepared than the other waves, with many vacinated people [90% da população-alvo na Espanha] and with an alert population”, reassures Muñoz, director of Microbiology of the Gregorio Marañón Hospital, in Madrid.
Virologist Inmaculada Casas directs the Spanish coronavirus genomic surveillance network and is in permanent contact with the European authorities. “The ability to control two antibodies produced in vacinated people is optimal against microns. The figures of hospitalizations and occupation of ICUs [por pessoas vacinadas] they are extremely low”, says Casas, citing preliminary data presented at the sixth fair by his South African colleagues. A virologist insists on the need to offer a third dose of the vaccine to the entire population, beginning with the most vulnerable groups and thus immunizing the children still before Natal. “The countries without access to the vaccine should be our priority,” warns the researcher, from the National Center for Microbiology, in the town of Majadahonda, in the Madrid region. Only 3 in every 100 people are fully vaccinated against covid-19 in the poorest countries on the planet.
Virologist Sonia Zúñiga is perplexed. A micron is so different from the other known variants that some scientists have cogitaram that the virus can evolve in parallel in animals before returning to humans. “It is a very real possibility, and it is something that is truly worrying, which will have to be thoroughly studied,” says Zúñiga, who works on an experimental vaccine against covid-19 at the National Center for Biotechnology of Spain, in Madrid. The researcher recalls that there have been more than a year registered in Denmark cases in which the coronavirus jumped to mink offspring due to officials who work with animals, and later turned to humans incorporating mutations acquired from mammals. “It would not be nonsense. Já aconteceu”, exclaims Zúñiga.
A more cogitated hypothesis, however, is that ômicron evolved for months in a person previously immunosuppressed by another doctor, like aids. About one in five South Africans is positive for or HIV. O coronavírus teria tido tempo de train against low defenses and desperate use of antivirals. One year ago, a 45-year-old man with antiphospholipid syndrome —an immune system problem— remained hospitalized with covid-19 for five months in a Boston hospital, until he died. His medical team detected at the time “an accelerated evolution of the virus”, with the appearance of mutations Y144-, T478K, E484A and N501Y. As four are also in the micron.
The countries without access to vacina should be our priority
Inmaculada Casas, virologist
Inmaculada Casas highlights an excellent piece of news. The micron mutations should not affect the activity of two very promising new treatments against covid-19, or paxlovid, a Pfizer drug that prevents 89% of hospitalizations and deaths, and molnupiravir, an MSD laboratory product whose efficacy reaches 30% . In the 30,000 letters of the coronavirus there are instructions to make the proteins from its structure, such as its spikes and its membrane, but there are also guidelines to produce unstructured proteins, which simply participate in the virus multiplication process. That’s where paxlovid and molnupiravir come in. And because there are no mutations in stretches of the genome. “As pessoas como o vírus ômicron poderiam treat with esses antivirais”, reassures Casas.
Já o Colombian virologist Javier Jaimes, from Cornell University (USA), worries in apparent detail. Based on genomic data, Nextstrain shows a unique sequence of a virus of the micron variant obtained in a patient from Botswana. These 30,000 letters include a mutation that should not be there: to P681R. “It is a mutation of the delta. Isso sim would be worrying. It would be a cereja do bolo para a ômicron”, warns Jaimes.
The spicule of the coronavirus is in the form of a cogumelo. Viruses need to cut through the head of the cocoon to start invading the human cell. For this first cut we use furin, a protein that works like a treasure. Jaimes’ bioinformatic simulations suggest that two micron mutations, to P681H and N679K, “slightly” facilitate this process. “This could facilitate the spread of the virus”, observes the scientist.
The sequence from Botswana does not have the P681H mutation characteristic of the micron, and just another in the same place: P681R, associated with the unusual contagiousness of the delta variant, which dominated the world for several months after being discovered in India, a year ago. The exceptional case of Botswana is like seeing a Frankenstein version of something that was um Frankenstein. “At this time, only one sequence was communicated, but this does not mean that others could not appear,” warns Jaimes.
Scientists from the Weizmann Institute, in Israel, will calculate in June that all the SARS-CoV-2 coronaviruses that infect humanity, together, would weigh something between 100 grams and 10 kilos. In other words: those blamed for the pandemic weigh less than a supermarket bag. It is possible that all the viruses of the micron variant of the planet weigh less than a gram, but will cause the date of borders in the world.
