Omicron: You may forget the COVID-19 variant but here's why your T-cells won't
2 years, 11 months ago

Omicron: You may forget the COVID-19 variant but here's why your T-cells won't

Firstpost  

The view that the immune system — prepped via either recovery from infection, or vaccination — can tackle the new variant has found support in a South African study that credits T-cells with putting up a robust defence against Omicron Countries are going into fresh curfews and restrictions are coming back again amid fresh surges under the shadow of the Omicron variant of the novel coronavirus. The so-called first line of defence, says the World Health Organisation, is the body’s ‘innate immunity’, which is the “general immediate response to any infection". Move past that and the virus encounters ‘adaptive immunity’, which is the “specific response to an infection" built via cellular response — the T cells — and the antibody response, which involves what are known as memory B cells. “Similarly, the development of memory T cells directed at non-surface Sars-CoV-2 proteins following infection or vaccination may offer a route to durable immunity where virus evolution leads to spike protein mutations that escape pre-existing neutralising antibodies," it adds.

Vaccination South Africa Infection Virus Cells System Immune Immunity Variant Omicron Memory B Cells T Cells Cell Response T Cell Immunity T Cell Responses  covid19  virus  omicron  forget  tcells  wont  vaccination  heres  immunity  variant  system  infection  immune  cell  response  cells

History of this topic

High Levels of Exposure to Covid Virus May Reduce Protection from Vaccination, Prior Infection: Study
1 year, 4 months ago

High Levels of Exposure to Covid Virus May Reduce Protection from Vaccination, Prior Infection: Study

News 18  

High levels of exposure to the SARS-CoV-2 virus may reduce or overcome the protection that COVID-19 vaccination and prior infection provides, according to a study conducted in the US. Hybrid immunity provided the highest level of protection, at 95 per cent and 71 per cent effectiveness, in residents without a documented exposure and with a cell exposure, respectively, according to …

High levels of exposure to Covid virus may reduce protection from vaccination, prior infection: Study
1 year, 4 months ago

High levels of exposure to Covid virus may reduce protection from vaccination, prior infection: Study

Hindustan Times  

High levels of exposure to the SARS-CoV-2 virus may reduce or overcome the protection that COVID-19 vaccination and prior infection provides, according to a study conducted in the US. Specifically, during the Delta wave, vaccination was 68 per cent effective at preventing infection in residents without a documented exposure but was just 26 per cent effective in residents with exposure …

You know those folks who had COVID but no symptoms? A new study offers an explanation
1 year, 5 months ago

You know those folks who had COVID but no symptoms? A new study offers an explanation

NPR  

You know those folks who had COVID but no symptoms? A new study offers an explanation Enlarge this image toggle caption CNRI / Science Source CNRI / Science Source Do you know someone who tested positive for COVID but never felt a darn thing? Bone marrow donors were key to the study Jill Hollenbach, an immunologist at the University of …

Omicron variants evolve strategies to evade T cell immunity
1 year, 8 months ago

Omicron variants evolve strategies to evade T cell immunity

The Hindu  

Much like many other viruses that have developed strategies to evade T cell-mediated clearance by humans, SARS-CoV-2 virus too has the ability to evade the CD8 T cells. But the authors found that the Omicron subvariants had a “superior capacity” to suppress MHC I levels on the surface of the cells infected by the virus compared with the ancestral strain …

COVID-19 survivors develop natural immunity against severe illnesses: Lancet
1 year, 10 months ago

COVID-19 survivors develop natural immunity against severe illnesses: Lancet

Live Mint  

Protection against COVID-19 re-infection is very high, found a study by The Lancet. For those who had at least one prior infection with COVID-19, natural immunity against severe illness was potent and enduring for all variations. Previous exposure to pre-Omicron variants significantly weakened natural immune defences against Omicron BA.1 reinfection. Also, the research reveals that the amount and duration of …

Covid-19’s spread in China might tell us how deadly Omicron really is
1 year, 11 months ago

Covid-19’s spread in China might tell us how deadly Omicron really is

Live Mint  

Covid-19’s rapid spread in China has prompted reports of crowded hospitals and inundated crematoria. China is meeting the Omicron variant with less exposure to the virus and lower vaccination rates among the elderly, public-health experts said. Covid-19’s spread there will help explain to what extent lower rates of severe disease and death are influenced by Omicron’s nature compared with a …

Covid-19’s spread in China might tell us how deadly Omicron really is
2 years ago

Covid-19’s spread in China might tell us how deadly Omicron really is

Live Mint  

Covid-19’s rapid spread in China has prompted reports of crowded hospitals and inundated crematoria. China is meeting the Omicron variant with less exposure to the virus and lower vaccination rates among the elderly, public-health experts said. Covid-19’s spread there will help explain to what extent lower rates of severe disease and death are influenced by Omicron’s nature compared with a …

Next Covid-19 Strain May Be More Dangerous, Says New Study
2 years ago

Next Covid-19 Strain May Be More Dangerous, Says New Study

News 18  

While China is experiencing a sudden surge in COVID cases, the rest of the world is comparatively doing better with the current Omicron strain in retreat mode. However, our concerns may be far from over as a new lab report says that the next COVID-19 variant may be way more dangerous than the Omicron strain. This study has been conducted …

New Omicron sub-variants: 5 ways mild Covid infections are affecting our health
2 years, 1 month ago

New Omicron sub-variants: 5 ways mild Covid infections are affecting our health

Hindustan Times  

New Omicron sub-variants are spreading across the world rapidly but the panic associated with Covid-19 is comparatively less compared to a year back considering the symptoms associated with Omicron have largely been mild. Omicron XBB the latest variant with its immune-evasive properties can dodge host's immune response and is highly infectious but it causes only mild symptoms in those vaccinated. …

Omicron infections provide protection against new COVID-19 variants, says study
2 years, 3 months ago

Omicron infections provide protection against new COVID-19 variants, says study

India TV News  

Vaccinated people who were infected by the earlier Omicron subvariants have four times greater protection than vaccinated people who were not infected against the new variants like BA.5, finds a new study. The study indicates that previous infection in vaccinated people continues to confer immunity for the variants that are known for their ability to evade the immune response. "Vaccinated …

How Omicron's BA.5 became a master of disguise, and what it means for COVID-19 surge
2 years, 4 months ago

How Omicron's BA.5 became a master of disguise, and what it means for COVID-19 surge

Firstpost  

BA.5 will not be the endgame. As the virus continues to circulate, this evolutionary trend will likely lead to the emergence of more transmissible variants that are capable of immune escape The omicron subvariant known as BA.5 was first detected in South Africa in February 2022 and spread rapidly throughout the world. Soon after researchers in South Africa reported the …

Novel COVID-19 vaccine offers superior protection against Omicron variants
2 years, 5 months ago

Novel COVID-19 vaccine offers superior protection against Omicron variants

Firstpost  

The vaccine, called Omnivax, increases neutralising antibody response against the BA.1 and BA.2.12.1 Omicron subvariants in pre-immunised mice 19-fold and eight-fold, respectively, compared with standard mRNA vaccines Washington: Scientists in the US have developed a new COVID-19 vaccine that offers superior immune protection against two viral subvariants of Omicron than standard mRNA shots. The vaccine, called Omnivax, increased neutralising antibody …

Too early to fully understand the nature and severity of BA.2.75: experts
2 years, 5 months ago

Too early to fully understand the nature and severity of BA.2.75: experts

The Hindu  

Top scientists and doctors in India said on Thursday that it’s too early to understand the nature and severity of the new sub-variant of Omicron — BA.2.75 — reported in the country. “About this new variant — so far there is no data available, except the increasing COVID numbers, which makes it difficult to arrive at any conclusion about the …

Omicron BA.5: How dangerous is it? What protection can vaccines offer?
2 years, 6 months ago

Omicron BA.5: How dangerous is it? What protection can vaccines offer?

Hindustan Times  

Due to the global increase in coronavirus cases caused by the BA.5 subvariant, the World Health Organization currently classifies it as a "variant of concern." Germany's Robert Koch Institute, the country's national public health organization, reported on June 9 that the omicron subvariants BA.4 and BA.5 are growing faster than all other variants and concluded the two could soon be …

The Omicron subvariant spreading across the U.S. shares an ominous trait with Delta
2 years, 6 months ago

The Omicron subvariant spreading across the U.S. shares an ominous trait with Delta

LA Times  

Coronavirus particles are seen under a microscope. A genetic trait that harks back to the pandemic’s past, known as a Delta mutation, appears to allow the virus “to escape preexisting immunity from vaccination and prior infection, especially if you were infected in the Omicron wave,” said Dr. Wesley Long, a pathologist at Houston Methodist in Texas. The Omicron subvariant gaining …

Omicron infection better at upping immunity than boosters, claims study
2 years, 7 months ago

Omicron infection better at upping immunity than boosters, claims study

India Today  

As coronavirus continues to infect people across the world, the latest trends in India show that hospitalisation rates are very low and the recovery is faster. A new study now reveals that Omicron infections produced even better immune responses than a booster shot in vaccinated people. The study conducted by vaccine maker BioNTech SE and the University of Washington reassures …

What do we know about “stealth omicron” so far?
2 years, 8 months ago

What do we know about “stealth omicron” so far?

Associated Press  

What do we know about “stealth omicron” so far? It was given the “stealth” nickname because it looks like the earlier delta variant on certain PCR tests, says Kristen Coleman at the University of Maryland School of Public Health. In rare cases, early research indicates BA.2 can infect people even if they’ve already had an omicron infection. Health officials also …

Booster dose of COVID-19 vaccine needed to fight against Omicron, says study
2 years, 8 months ago

Booster dose of COVID-19 vaccine needed to fight against Omicron, says study

Firstpost  

New Delhi: Neutralising antibody levels waned after six months in those who were fully vaccinated against the coronavirus with Covishield, Covaxin and a mix of both — Covishield as the first dose and Covaxin as the second dose with regard to Omicron variant, a study done by the National Institute of Virology in Pune has indicated. The heterologous vaccination regimen …

Next COVID variant can be severe as Delta, immune evasive like Omicron
2 years, 9 months ago

Next COVID variant can be severe as Delta, immune evasive like Omicron

Live Mint  

In a worrying sign, scientists have suggested that the next COVID variant can cause severe infections like the Delta, Alpha variant and also show immune escape properties like the Omicron. “It is possible that a later variant may be back to a Delta or Alpha lineage, with sufficient immune evasion to sweep Omicron away,” Andrew Rambaut, who studies viral evolution …

Op-Ed: Will the next coronavirus variant escape our best immune defenses?
2 years, 9 months ago

Op-Ed: Will the next coronavirus variant escape our best immune defenses?

LA Times  

An image of the coronavirus, shown as orange, emerging from the surface of cells, in green, cultured in a lab. Studies show that the strength of our long-lived T-cell response to the virus’ proteins — especially by T cells that recognize the spike protein — strongly correlates with the degree of protection. Rather, T-cell recognition occurs when a viral protein …

Is omicron leading us closer to herd immunity against COVID?
2 years, 10 months ago

Is omicron leading us closer to herd immunity against COVID?

Associated Press  

Is omicron leading us closer to herd immunity against COVID-19? Experts say it’s not likely that the highly transmissible variant — or any other variant — will lead to herd immunity. “ Herd immunity is an elusive concept and doesn’t apply to coronavirus,” says Dr. Don Milton at the University of Maryland School of Public Health. Herd immunity is when …

Covid vaccine efficacy limited against Omicron, says study
2 years, 10 months ago

Covid vaccine efficacy limited against Omicron, says study

India Today  

People who are double-vaccinated and those who have recovered from infection by previous strains of the SARS-CoV-2 virus have virtually no antibody protection against the Omicron variant, according to a study. Read: Very small blood clot risk after first AstraZeneca Covid shot, say UK studies They adapted for Omicron a test developed for the previous variants, which investigates whether the …

New Covid variants complicate the question of vaccine mandates
2 years, 10 months ago

New Covid variants complicate the question of vaccine mandates

Hindustan Times  

Post-infection immunity might be a strange topic for political strife, but it touches on Covid vaccine mandates and whether those who’ve had the virus should be exempt. “But I think it’s more nuanced now, and a lot of people think natural immunity gives you a substantial level of protection.” But how much protection, compared to vaccination? “That’s not clear.” Barouch …

Next Covid-19 variant will be more infectious than Omicron, possibly deadlier, warns WHO
2 years, 10 months ago

Next Covid-19 variant will be more infectious than Omicron, possibly deadlier, warns WHO

India Today  

Even as the world limps back to normalcy with the Omicron wave subsiding, experts have warned that the next Covid-19 variant will be more transmissible, and perhaps, more deadly than its predecessors. In a recent press briefing, World Health Organization epidemiologist and technical lead on Covid-19 Dr Maria Van Kerkhove stressed that the pandemic is far from over and future …

Booster does up protection against Omicron to 68%: RIVM research
2 years, 10 months ago

Booster does up protection against Omicron to 68%: RIVM research

Dutch News  

While vaccinations or a previous coronavirus infection provide less effective protection against the Omicron variant when compared with Delta, a booster does ensure renewed protection, according to new research by public health institute RIVM. After a booster vaccination, protection against infection with Delta rose to 93% and to 68% for Omicron, the RIVM research shows. ‘International research shows that protection …

Omicron amps up concerns about long COVID and its causes
2 years, 10 months ago

Omicron amps up concerns about long COVID and its causes

Associated Press  

More than a year after a bout with COVID-19, Rebekah Hogan still suffers from severe brain fog, pain and fatigue that leave her unable to do her nursing job or handle household activities. In her lab at Stellenbosch University in South Africa, scientist Resia Pretorius has found microclots in blood samples from patients with COVID-19 and in those who later …

Immune response induced by Omicron effectively neutralise Delta variant: ICMR study
2 years, 10 months ago

Immune response induced by Omicron effectively neutralise Delta variant: ICMR study

Deccan Chronicle  

New Delhi: An ICMR study has demonstrated that individuals infected with Omicron have significant immune response which could neutralise not only the Omicron, but also other variants of concern, including the most prevalent Delta variant. It suggests that the immune response induced by the Omicron could effectively neutralise the Delta variant, making the re-infection with Delta variant less likely, thereby …

Covid-19 is less severe with Omicron than Delta, suggests US study
2 years, 10 months ago

Covid-19 is less severe with Omicron than Delta, suggests US study

Live Mint  

The Omicron variant appears to result in less severe COVID-19 than seen during previous periods of high coronavirus transmission including the Delta wave, with shorter hospital stays, less need for intensive care and fewer deaths, according to a new U.S. study. Despite the steep spike in COVID cases, the percentage of hospitalized patients admitted to intensive care units during the …

Explained: Why antibodies become ineffective against Omicron
2 years, 10 months ago

Explained: Why antibodies become ineffective against Omicron

India TV News  

The presence of a large number of mutations, and more than 30 on its spike protein makes antibodies ineffective against the Omicron variant of Covid-19, shows a study. Further, the team used a preexisting S-protein structure, one which would theoretically prevent the binding of antibodies to a virus, to assess whether or not the Omicron mutations would similarly affect the …

Current Covid vaccines may protect from severe disease caused by Omicron: Study
2 years, 10 months ago

Current Covid vaccines may protect from severe disease caused by Omicron: Study

Deccan Chronicle  

Washington: Current COVID-19 vaccines prompt the body to make effective, long-lasting T cells against SARS-CoV-2 that can recognise variants of concern, including Omicron, and protect from severe disease, a study has found. The research, published in the journal Cell, also shows that fully vaccinated people have fewer memory B cells and neutralising antibodies against the Omicron variant. "Most of the …

Why Omicron variant is less severe than Delta
2 years, 11 months ago

Why Omicron variant is less severe than Delta

India TV News  

Highlights Omicron variant of Covid is highly contagious but is known to cause less severe disease than Delta Researchers from University of Kent and Goethe-University Frankfurt, provides the first explanation Omicron variant, first detected in late November, has swiftly spread to 171 countries so far The Omicron variant of Covid is highly contagious but is known to cause less severe …

Omicron will soon replace Delta globally due to 'immunity evading potential': WHO
2 years, 11 months ago

Omicron will soon replace Delta globally due to 'immunity evading potential': WHO

India TV News  

Highlights WHO on Sunday said that the Omicron variant of Covid 19 has been identified in 171 countries. The global health body said that Omicron is soon set to replace Delta globally. In its latest technical brief, the global health body said that Omicron is soon set to replace Delta globally as a result of its immunity evading potential. "Omicron …

Booster shots needed against omicron, CDC studies show
2 years, 11 months ago

Booster shots needed against omicron, CDC studies show

Associated Press  

NEW YORK — Three studies released Friday offered more evidence that COVID-19 vaccines are standing up to the omicron variant, at least among people who received booster shots. The papers echo previous research — including studies in Germany, South Africa and the U.K. — indicating available vaccines are less effective against omicron than earlier versions of the coronavirus, but also …

Is Omicron the end game of Covid-19? Study in South Africa may have an answer
2 years, 11 months ago

Is Omicron the end game of Covid-19? Study in South Africa may have an answer

India Today  

When will the Covid-19 pandemic end? This is where studies conducted in South Africa which reported Omicron first to the World Health Organization in mid-November last year, and where scientists have devoted a lot of time and resources understanding the variant bring cheer amid the Covid-19 gloom. In a South African laboratory study, researchers found those previously infected with the …

Booster shots needed against Omicron, CDC studies show
2 years, 11 months ago

Booster shots needed against Omicron, CDC studies show

LA Times  

A dose of a Pfizer COVID-19 vaccine is prepared at Lurie Children’s hospital on Nov. 5, 2021, in Chicago. Three studies released Friday offered more evidence that COVID-19 vaccines are standing up to the Omicron variant, at least among people who received booster shots. The papers echo previous research — including studies in Germany, South Africa and the U.K. — …

COVID-19 vaccine booster provides effective antibody protection against Omicron, says Lancet study
2 years, 11 months ago

COVID-19 vaccine booster provides effective antibody protection against Omicron, says Lancet study

Firstpost  

COVID-19 Vaccine Booster | The study found that in people who had received the Pfizer vaccine for all three doses, antibody levels against Omicron after a third dose were similar to those previously reached against Delta after only two shots. London: A third dose of COVID-19 vaccine increases the level of antibodies that can effectively neutralise the Omicron variant of …

How the body’s immune system tries to fight off COVID-19
2 years, 11 months ago

How the body’s immune system tries to fight off COVID-19

LA Times  

Vaccines and the antibodies they generate are just one piece of the puzzle when it comes to fighting off the coronavirus, pictured, that causes COVID-19. Here‘s a breakdown of how the body’s immune system works and how it’s been tested by Omicron: B cells, T cells, NKs and DCs Think of the immune system as having three layers of defense. …

‘Mild’ COVID Doesn't Mean What You Think It Does
2 years, 11 months ago

‘Mild’ COVID Doesn't Mean What You Think It Does

Huff Post  

Dalibor Despotovic via Getty Images As omicron cases explode in the United States, health officials have offered stark warnings about our collective future. It’s also problematic because many people’s sense of what it means to have a “mild” case of COVID-19 is really. If you can — even if that means you’re really not able to do anything, and you …

A fourth vaccine dose doesn't seem to fully stop omicron, study finds
2 years, 11 months ago

A fourth vaccine dose doesn't seem to fully stop omicron, study finds

Salon  

Besides being incredibly contagious, COVID-19's omicron variant is frightening for its vaccine-resistant properties. Hence, two weeks ago, a group of Israeli scientists studied whether the existing Pfizer-BioNTech vaccine can protect against omicron infections if patients are given four doses of vaccine, meaning a two-shot vaccine and two boosters. RELATED: Omicron's lower mortality rate may be explained by how the variant …

Explained: Why T cell vaccines could be the key to long-term immunity from COVID-19
2 years, 11 months ago

Explained: Why T cell vaccines could be the key to long-term immunity from COVID-19

Firstpost  

Many of the doses designed to date – including Moderna’s, Pfizer’s and AstraZeneca’s – have focused just on the spike protein of the coronavirus. The main types are B cells, which make antibodies, and T cells, which either support B cell antibody production or act as killer cells to destroy the virus. This knowledge suggests that, against COVID, a good …

Omicron Scare: Does booster dose really neutralizes COVID-19's new variant?
2 years, 11 months ago

Omicron Scare: Does booster dose really neutralizes COVID-19's new variant?

India TV News  

An international team of researchers recently studied the sensitivity of Omicron to antibodies compared with the currently dominant Delta variant. In a new study supported by the European Union's Health Emergency Preparedness and Response Authority, scientists from the Institut Pasteur and the Vaccine Research Institute, in collaboration with KU Leuven, Orleans Regional Hospital, Hospital Europeen Georges Pompidou and Inserm, studied …

Explained | Is vaccination limiting Omicron’s virulence?
2 years, 11 months ago

Explained | Is vaccination limiting Omicron’s virulence?

The Hindu  

The story so far : Omicron, the latest SARS-CoV-2 variant of concern, may be pushing up COVID numbers across the world but it is also reporting a lower rate of hospitalisation and deaths compared to the previous Delta waves so far. According to WHO, the threat posed by Omicron largely depends on four key questions -- how transmissible the variant …

COVID19: Omicron is 91 per cent less likely to cause death in infected patients, says CDC
2 years, 11 months ago

COVID19: Omicron is 91 per cent less likely to cause death in infected patients, says CDC

India TV News  

The Omicron variant is significantly less severe than other strains of Covid-19, according to a report from the US Centres for Disease Control and Prevention. Among people hospitalised, they were 75 per cent less likely to require intensive care, and even the rate of mortality was 91 per cent lower than that of Delta. Currently, the US is averaging 750,515 …

COVID-19 testing is necessary to break the chain of transmission, says health expert
2 years, 11 months ago

COVID-19 testing is necessary to break the chain of transmission, says health expert

Deccan Chronicle  

New Delhi: Amid the continuous rise in COVID-19 cases driven by the Omicron variant, a health expert says it is important that we get tested to break the chain of transmission as avoiding the test and just assuming the presence or absence of COVID infection will lead to carelessness. Therefore, it is important that you get yourself tested and then …

T-cell responses offer protection against Omicron variant of Covid: Study
2 years, 11 months ago

T-cell responses offer protection against Omicron variant of Covid: Study

Hindustan Times  

A new study has claimed that T-cells present in the human body offer protection against the fast-spreading Omicron variant of Covid-19. Previously, researchers and scientists have also said that 70-80% of T-cell responses are able to fight the Omicron variant. "SARS-CoV-2 T cell responses induced by either natural infection or vaccines have been linked to rapid viral clearance and reduced …

Explained | Why you should still try to avoid catching Omicron
2 years, 11 months ago

Explained | Why you should still try to avoid catching Omicron

India Today  

A fast-spreading Omicron variant that causes milder illness compared with previous versions of the coronavirus has fueled the view that Covid-19 poses less of a risk than in the past. OMICRON'S LONG-TERM EFFECTS ARE UNKNOWN Infections with earlier variants of the coronavirus, including mild infections and "breakthrough" cases after vaccination, sometimes caused the lingering, debilitating long-haul Covid syndrome. Also unclear …

Omicron is not common cold, warns Centre
2 years, 11 months ago

Omicron is not common cold, warns Centre

The Hindu  

Omicron infection is not common cold, the Union Health Ministry warned on Wednesday, adding that fully vaccinated people were 78% less likely to develop COVID-19 infection than unvaccinated people. Quoting a study by the New York State Health Department, Lav Agarwal, Joint Secretary, Health Ministry, said the report, based on analysis since May 2021, also showed that fully vaccinated people …

Omicron quickly overtaking Delta globally in terms of circulation: WHO
2 years, 11 months ago

Omicron quickly overtaking Delta globally in terms of circulation: WHO

Live Mint  

United Nations/Geneva: Omicron is quickly overtaking the Delta variant of COVID-19 and becoming dominant around the world, a senior WHO official has warned, with the global health agency cautioning that there is "increasing evidence" Omicron is able to evade immunity but has less disease severity as compared to other variants. It could take some time for Omicron to overtake Delta …

Omicron quickly overtaking Delta globally in terms of circulation: WHO
2 years, 11 months ago

Omicron quickly overtaking Delta globally in terms of circulation: WHO

Deccan Chronicle  

United Nations/Geneva: Omicron is quickly overtaking the Delta variant of COVID-19 and becoming dominant around the world, a senior WHO official has warned, with the global health agency cautioning that there is "increasing evidence" Omicron is able to evade immunity but has less disease severity as compared to other variants. She further cautioned that even though there is some information …

Omicron 'not mild disease', still causing hospitalisation: WHO
2 years, 11 months ago

Omicron 'not mild disease', still causing hospitalisation: WHO

India TV News  

Highlights Omicron variant is quickly overtaking the Delta variant of COVID-19, the WHO has said Omicron has been detected in all countries where we have good sequencing, it said Omicron is becoming the dominant variant that is being detected, the WHO has said There is increasing evidence to show the Omicron variant is able to evade immunity but has less …

Discover Related