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New evidence COVID-19 antibodies, vaccines less effective against variants; Study

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Worrisome new coronavirus variants can evade antibodies that neutralize original virus

(Asian News Hub) – New research at Washington University School of Medicine in St. Louis indicates that three new, fast-spreading variants of the virus that cause COVID-19 can evade antibodies that work against the original form of the virus that sparked the pandemic.

With few exceptions, whether such antibodies were produced in response to vaccination or natural infection, or were purified antibodies intended for use as drugs, the researchers found more antibody is needed to neutralize the new variants.


The findings, from laboratory-based experiments and published March 4 in Nature Medicine, suggest that COVID-19 drugs and vaccines developed thus far may become less effective as the new variants become dominant, as experts say they inevitably will. The researchers looked at variants from South Africa, the United Kingdom and Brazil.


“We’re concerned that people whom we’d expect to have a protective level of antibodies because they have had COVID-19 or been vaccinated against it, might not be protected against the new variants,” said senior author Michael S. Diamond, MD, PhD, the Herbert S. Gasser Professor of Medicine.

“There’s wide variation in how much antibody a person produces in response to vaccination or natural infection. Some people produce very high levels, and they would still likely be protected against the new, worrisome variants. But some people, especially older and immunocompromised people, may not make such high levels of antibodies. If the level of antibody needed for protection goes up tenfold, as our data indicate it does, they may not have enough. The concern is that the people who need protection the most are the ones least likely to have it.”


The virus that causes COVID-19, known as SARS-CoV-2, uses a protein called spike to latch onto and get inside cells. People infected with SARS-CoV-2 generate the most protective antibodies against the spike protein.


Consequently, spike became the prime target for COVID-19 drug and vaccine developers.

The three vaccines authorized by the Food and Drug Administration (FDA) for emergency use in the U.S. — made by Pfizer/BioNTech, Moderna and Johnson & Johnson — all target spike. And potent anti-spike antibodies were selected for development into antibody-based drugs for COVID-19.


Viruses are always mutating, but for nearly a year the mutations that arose in SARS-CoV-2 did not threaten this spike-based strategy. Then, this winter, fast-spreading variants were detected in the United Kingdom, South Africa, Brazil and elsewhere.

Sparking concern, the new variants all carry multiple mutations in their spike genes, which could lessen the effectiveness of spike-targeted drugs and vaccines now being used to prevent or treat COVID-19. The most worrisome new variants were given the names of B.1.1.7 (from the U.K.), B.1.135 (South Africa) and B.1.1.248, also known as P.1 (Brazil).


To assess whether the new variants could evade antibodies made for the original form of the virus, Diamond and colleagues, including first author Rita E. Chen, a graduate student in Diamond’s lab, tested the ability of antibodies to neutralize three virus variants in the laboratory.


The researchers tested the variants against antibodies in the blood of people who had recovered from SARS-CoV-2 infection or were vaccinated with the Pfizer vaccine.

They also tested antibodies in the blood of mice, hamsters and monkeys that had been vaccinated with an experimental COVID-19 vaccine, developed at Washington University School of Medicine, that can be given through the nose.

The B.1.1.7 (U.K.) variant could be neutralized with similar levels of antibodies as were needed to neutralize the original virus. But the other two variants required from 3.5 to 10 times as much antibody for neutralization.

Then, they tested monoclonal antibodies: mass-produced replicas of individual antibodies that are exceptionally good at neutralizing the original virus. When the researchers tested the new viral variants against a panel of monoclonal antibodies, the results ranged from broadly effective to completely ineffective.


Since each virus variant carried multiple mutations in the spike gene, the researchers created a panel of viruses with single mutations so they could parse out the effect of each mutation.

Most of the variation in antibody effectiveness could be attributed to a single amino acid change in the spike protein. This change, called E484K, was found in the B.1.135 (South Africa) and B.1.1.248 (Brazil) variants, but not B.1.1.7 (U.K.).

The B.1.135 variant is widespread in South Africa, which may explain why one of the vaccines tested in people was less effective in South Africa than in the U.S., where the variant is still rare, Diamond said.


“We don’t exactly know what the consequences of these new variants are going to be yet,” said Diamond, also a professor of molecular microbiology and of pathology & immunology.

“Antibodies are not the only measure of protection; other elements of the immune system may be able to compensate for increased resistance to antibodies.

That’s going to be determined over time, epidemiologically, as we see what happens as these variants spread. Will we see reinfections? Will we see vaccines lose efficacy and drug resistance emerge? I hope not.

But it’s clear that we will need to continually screen antibodies to make sure they’re still working as new variants arise and spread and potentially adjust our vaccine and antibody-treatment strategies.”


The research team also included co-corresponding author Ali Ellebedy, PhD, an assistant professor of pathology & immunology, of medicine, and of molecular microbiology at Washington University; and co-corresponding author Pei-Yong Shi, PhD, and co-first author Xianwen Zhang, PhD, of the University of Texas Medical Branch.

Washington University School of Medicine

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Moderna chief predicts existing COVID-19 vaccines will struggle with Omicron variant

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(Asian News Hub) – The chief executive of Moderna has just predicted that existing COVID-19 vaccines will be much less effective at tackling Omicron than earlier variants of SARS-CoV-2 and warned it would take months before pharmaceutical companies can manufacture new variant-specific jabs at scale, FR reported.

Stéphane Bancel said the high number of Omicron mutations on the spike protein, which the virus uses to infect human cells, and the suspected potential rapid spread of the variant in South Africa, suggested the current crop of COVID-19 vaccines may need to be modified next year to beat Omicron.

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“There is no world, I think, where [the effectiveness] is the same level, we had with Delta,” Bancel said.

He added: “I think it’s going to be a material drop. I just don’t know how much because we need to wait for the data. But all the scientists I’ve talked to . . . are like ‘this is not going to be good’.”

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Omicron has 30+ mutations in spike protein region, may bypass vaccines: Dr Guelria AIIMS chief

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Says efficacy of vaccines, including those in use in India, needs to be evaluated ‘critically’

(Asian News Hub) – The new Omicron variant of coronavirus has reportedly got over 30 mutations in the spike protein region giving it the potential to develop a immunoescape mechanism, and thus the efficacy of vaccines against it needs to be evaluated critically, PTI reported as saying by AIIMS chief Dr Randeep Guelria.

The presence of spike protein facilitates a virus’ entry into the host cell and is responsible for making it transmissible and causing infection.

Also Read: As new Covid variant surfaces, Doctors body calls for enhanced genome sequencing

“The new variant of coronavirus reportedly has got more than 30 mutations in the spike protein region and therefore has the potential of developing immunoescape mechanisms. As most vaccines (work by) forming antibodies against the spike protein, so many mutations at the spike protein region may lead to a decreased efficacy of COVID-19 vaccines,” AIIMS Director Dr Randeep Guelria told PTI.

In such a scenario, the efficacy of vaccines, including those in use in India, needs to be evaluated “critically”, he said.

The future course of action will depend on what more data on its transmissibility, virulence and immunoescpae shows, he said.

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The Indian SARS-CoV-2 Genomic Consortia INSACOG is closely tracking the new variant of COVID-19 called B.1.1.529 and its presence has not been detected yet in the country, officials have said.

Dr Guleria emphasised the need to be very vigilant and having aggressive surveillance both for international travellers and in the region where there is a sudden increase in the number of cases.

“Also, we must ask everyone to religiously follow Coivd-appropriate behaviour and not let their guards down. Also, it has to be ensured that people get both the doses of vaccine and those who have not yet taken the jab are encouraged to come forward to take it,” he said.

The new, and potentially more contagious variant, was first reported to the World Health Organization (WHO) from South Africa on November 24. It has since been identified in Botswana, Belgium, Hong Kong and Israel among other countries.

On Friday, it was designated a ‘Variant of Concern’ by the WHO, which named it Omicron. A ‘Variant of Concern’ is the WHO’s top category of worrying Covid-19 strain.

The Centre on Thursday asked all states and union territories to conduct rigorous screening and testing of all international travellers coming from or transiting through South Africa, Hong Kong and Botswana.

In a letter to the additional chief secretary/principal secretary/secretary (Health) of all states and union territories, Union Health Secretary Rajesh Bhushan asked them to ensure that samples of travellers turning positive are sent to the designated genome sequencing laboratories promptly.

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As new Covid variant surfaces, Doctors body calls for enhanced genome sequencing

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DAK President

(Asian News Hub) – With the emergence of a new Covid-19 variant carrying worrisome mutations, Doctors Association Kashmir (DAK) on Saturday called for enhanced genome sequencing of Covid-19 positive samples to look for the variant in the valley.

“We need to expedite the genome sequencing to identify the variant early and protect the community from another wave of Covid-19,” said DAK President and Influenza expert Dr Nisar ul Hassan.

Also Read: J&K records lowest fertility rate in India

“Picking up the variant early is key to formulate appropriate and effective health policy that would help prevent and control its spread in the community,” he said.

The DAK President said genome sequencing is a laboratory method that is used to identify changes (mutations) in the genetic structure of the virus.

“A new variant of Covid-19 B.1.1.529 has surfaced in South Africa and has also been identified in Botswana, Belgium, Hong Kong and Israel,” he said.

Dr Hassan said the variant has 32 mutations in the region of the genome that controls production of the viral spike protein.

“The spike protein of the virus is critical for viral binding and entry to human cells. It is also the chief target of antibodies that the immune system produces to fight Covid-19 infection.” he added.  

“Dubbed as Omicron, WHO has designated the new variant as variant of Concern,” said Dr Nisar.

He said a variant is labeled as variant of concern when the evidence shows the virus is more infectious, is causing more severe disease and is less responsive to existing control measures such as diagnostics, vaccine or treatment or a combination of these factors.

“South Africa has reported a fourfold increase in the number of new cases coinciding with the emergence of the new variant. 

Many countries including Europe, US and Canada has imposed travel restrictions from South Africa and several other African countries,” he added.

Spokesperson DAK Dr Riyaz Amad Dagga said in today’s connected world, an outbreak anywhere is a risk everywhere.

Kashmir being the most favorite tourist destination, the mutant can come to us anytime. We have to be prepared and alert.

“We have to prepare in advance,” he said adding advance planning and preparedness is critical to help mitigate the impact of any eventuality.

General Secretary DAK Dr Arshad Ali said the best way to prevent the variant is to stop it from coming in as once the virus enters the community it is difficult to control it.

“Passengers at Srinagar international airport especially coming from affected countries should be rigorously screened to prevent the entry and spread of the variant in the valley,” he said.

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