Tag Archives: omicron

Immune cells from the common cold offer protection against COVID-19, researchers find

If one in 10 cold infections are from coronaviruses, then antibodies produced from these illnesses could surely give a bit more protection against COVID-19, right? A new study has just provided the answer to this question by showing that immunity induced by colds can indeed help fight off the far more dangerous novel coronavirus.

Image credits: Engin Akyurt.

A study from Imperial College London that studied people exposed to SARS-CoV-2 or COVID-19 found that only half of the participants were infected, while the others tested negative. Before this, researchers took blood samples from all volunteers within days of exposure to determine the levels of an immune cell known as a T cell – cells programmed by previous infections to attack specific invaders.

Results show that participants who didn’t test positive had significantly higher levels of these cells; in other words, those who evaded infection had higher levels of T cells that attack the Covid virus internally to provide immunity — T cells that may have come from previous coronavirus infections (not SARS-CoV-2). These findings, published in the journal Nature Communications, may pave the way for a new type of vaccine to prevent infection from emerging variants, including Omicron.

Dr. Rhia Kundu, the first author of the paper from Imperial’s National Heart & Lung Institute, says: “Being exposed to the SARS-CoV-2 virus doesn’t always result in infection, and we’ve been keen to understand why. We found that high levels of pre-existing T cells, created by the body when infected with other human coronaviruses like the common cold, can protect against COVID-19 infection.” Despite this promising data, she warns: “While this is an important discovery, it is only one form of protection, and I would stress that no one should rely on this alone. Instead, the best way to protect yourself against COVID-19 is to be fully vaccinated, including getting your booster dose.”

The common cold’s role in protecting you against Covid

The study followed 52 unvaccinated people living with someone who had a laboratory-confirmed case of COVID-19. Participants were tested seven days after being exposed to see if they had caught the disease from their housemates and to analyze their levels of pre-existing T cells. Tests indicated that the 26 people who tested negative for COVID-19 had significantly higher common cold T cells levels than the remainder of the people who tested positive. Remarkably, these cells targeted internal proteins within the SARS-CoV-2 virus, rather than the spike protein on its surface, providing ‘cross-reactive’ immunity between a cold and COVID-19.

Professor Ajit Lalvani, senior author of the study and Director of the NIHR Respiratory Infections Health Protection Research Unit at Imperial, explained:

“Our study provides the clearest evidence to date that T cells induced by common cold coronaviruses play a protective role against SARS-CoV-2 infection. These T cells provide protection by attacking proteins within the virus, rather than the spike protein on its surface.”

However, experts not involved in the study caution against presuming anyone who has previously had a cold caused by a coronavirus will not catch the novel coronavirus. They add that although the study provides valuable data regarding how the immune system fights this virus, it’s unlikely this type of illness has never infected any of the 150,000 people who’ve died of SARS-CoV-2 in the UK to date.

Other studies uncovering a similar link have also warned cross-reactive protection gained from colds only lasts a short period.

The road to longer-lasting vaccines

Current SARS-CoV-2 vaccines work by recognizing the spike protein on the virus’s outer shell: this, in turn, causes an immune reaction that stops it from attaching to cells and infecting them. However, this response wanes over time as the virus continues to mutate. Luckily, the jabs also trigger T cell immunity which lasts much longer, preventing the infection from worsening or hospitalization and death. But this immunity is also based on blocking the spike protein – therefore, it would be advantageous to have a vaccine that could attack other parts of the COVID virus.

Professor Lalvani surmises, “The spike protein is under intense immune pressure from vaccine-induced antibodies which drives the evolution of vaccine escape mutants. In contrast, the internal proteins targeted by the protective T cells we identified mutate much less. Consequently, they are highly conserved between the SARS-CoV-2 variants, including Omicron.” He ends, “New vaccines that include these conserved, internal proteins would therefore induce broadly protective T cell responses that should protect against current and future SARS-CoV-2 variants.”

New COVID variant identified in France — but experts say we shouldn’t fear it

Scientists have identified a previously unknown mutant strain in a fully vaccinated person who tested positive after returning from a short three-day trip to Cameroon.

Academics based at the IHU Mediterranee Infection in Marseille, France, discovered the new variant on December 10. So far, the variant doesn’t appear to be spreading rapidly and the World Health Organization has not yet labeled it a variant of concern. Nevertheless, researchers are still describing and keeping an eye on it.

The discovery of the B.1.640.2 mutation, dubbed IHU, was announced in the preprint server medRxiv, in a paper still awaiting peer review. Results show that IHU’s spike protein, the part of the virus responsible for invading host cells, carries the E484K mutation, which increases vaccine resistance. The genomic sequencing also revealed the N501Y mutation — first seen in the Alpha variant — that experts believe can make COVID-19 more transmissible.  

In the paper, the clinicians highlight that it’s important to keep our guard and expect more surprises from the virus: “These observations show once again the unpredictability of the emergence of new SARS-CoV-2 variants and their introduction from abroad,” they write. For comparison Omicron (B.1.1.529) carries around 50 mutations and appears to be better at infecting people who already have a level of immunity. Thankfully, a growing body of research proves it is also less likely to trigger severe symptoms.

Like many countries in Europe, France is experiencing a surge in the number of cases due to the Omicron variant.

Experts insist that IHU, which predates Omicron but has yet to cause widespread harm, should not cause concern – predicting that it may fade into the background. In an interview with the Daily Mail, Dr. Thomas Peacock, a virologist at Imperial College London, said the mutation had “a decent chance to cause trouble but never really materialized. So it is definitely not one worth worrying about too much at the moment.”

The strain was first uploaded to a variant tracking database on November 4, more than two weeks before Omicron was sequenced. For comparison, French authorities are now reporting over 300,000 new cases a day thought to be mostly Omicron, with data suggesting that the researchers have identified only 12 cases of IHU over the same period. 

On the whole, France has good surveillance for COVID-19 variants, meaning health professionals quickly pinpoint any new mutant strains. In contrast to Britain, which only checks three in ten cases for variants. The paper’s authors state that the emergence of the new variant emphasizes the importance of regular “genomic surveillance” on a countrywide scale.

Moderna booster offers reliable protection against Omicron variant

Three doses of the Moderna vaccine appear to provide significant protection against the new Omicron variant, the company said based on new data that has not yet been peer-reviewed. The announcement comes similar results were reported for the Pfizer/BioNTech vaccine: two doses offer little protection, but the third one does the trick.

Image credit: Flickr / The Focal Project.

Preliminary data from laboratory tests found that the booster from Moderna currently being used in the US and elsewhere provides increased antibody levels that can neutralize the virus. The pharmaceutical company said it’s currently working on an Omicron-specific booster (with clinical trials starting in 2022), but some experts believe the special booster may not be necessary, as even the normal dose seems to work fine. 

While two shots of the vaccine generated low levels of neutralizing antibodies against Omicron, a 50-microgram booster increased them 37-fold, Moderna said. A 100-microgram booster led to even higher antibody levels – more than 80 times compared to pre-boost level.

US regulators have so far authorized a 50-microgram booster of Moderna and a 100-microgram version for the first two doses. Moderna said the 100-microgram booster was safe and well tolerated, but with a trend toward more frequent adverse reactions, adding that it will now be up to governments and regulators to decide on its authorization.

“The dramatic increase in COVID-19 cases from the Omicron variant is concerning to all. However, these data showing that the currently authorized Moderna COVID-19 booster can boost neutralizing antibody levels 37-fold higher than pre-boost levels are reassuring,” Stéphane Bancel, Chief Executive Officer of Moderna, said in a statement.

Moderna’s news comes after the Pfizer/BioNTech booster was also found to provide a strong protection against the Omicron variant. Pfizer CEO Albert Bourla said earlier this month “the best course of action” to address a further spread of the Omicron variant was to get as many people as possible vaccinated with two doses as well as a booster. 

There are many uncertainties regarding the new variant, including its relationship with severe illness and its ability to dodge the body’s defenses. As Moderna, they are now working on a new vaccine specific for the Omicron variant, which should be ready in 2022 after approval from regulators. 

[Read: Here’s what we know about Omicron so far]

A growing spread

The new Omicron variant was first identified in South Africa in late November, though it may have emerged in another area. Since then, researchers and pharmaceutical companies have raced to better understand its properties and the risks that it represents. Preliminary data suggests Omicron spreads faster than the Delta variant and that can infect people immune to other variants.

Omicron has already been detected in 89 countries, with a “substantial growth advantage” over the Delta variant (which it seems to be displacing) the World Health Organization (WHO) said. The WHO classified Omicron as a variant of concern earlier this month, with cases currently doubling every 1.5 to 3 days in places where there is community spread, WHO said. 

Coronavirus cases are growing fast across Europe, largely driven by the Omicron variant. Many countries are imposing tighter restrictions to try to curb the virus, such as orders to work from home and limit opening hours in restaurants.. In the US cases are also rising rapidly, with Washington DC and New York reporting record daily numbers last Friday. 

UK faces new surge of COVID-19 infections due to Omicron variant

The Omicron Covid-19 variant, which appears to be more contagious than other previous strains of the virus, is expanding fast across the United Kingdom, and the government is preparing a new set of restrictions. The country has already registered the first death of a person with the variant, which is expected become dominant in London in the next few days.

UK Prime Minister Boris Johnson. Image credit: Flickr / Number 10.

As of Monday, there were 4,714 confirmed cases of Omicron in the UK, according to Health Secretary Sajid Javid speaking to Parliament, with the total daily infections with all strains estimated at 200,000. Javid said the new variant is spreading “at a phenomenal rate, doubling every two days in infections.” That’s something never seen before in the pandemic, he added.

The UK has already increased its Covid-19 alert level to four, which means a high or rising level of transmission — a level that hadn’t been seen in place since May. New guidelines were also implemented this week, asking people to work from home whenever possible and wear a mask when going to the shops and on public transportation — something that was previously not the case in Britain.

“Sadly at least one patient has now been confirmed to have died with Omicron,” Prime Minister Boris Johnson told reporters when visiting a vaccination center. “So I think the idea that this is somehow a milder version of the virus – I think that’s something we need to set on one side – and just recognize the sheer pace at which it accelerates.”

Johnson set the target of offering every adult a third Covid-19 vaccine by the end of December, a month earlier than originally planned. The government had already reduced the period between the second and third doses from six months to three – focusing its Covid response in vaccination instead on reimposing further restrictions.

The Prime Minister also said there’s “a tidal wave of Omicron” on its way to the UK but showed confidence on the booster shot, which could bring protection levels back up. Two doses of the Covid-19 vaccine “are simply not enough to give the level of protection we all need,” he added, encouraging people to get their new shot. 

The speech seemed to have had an effect, as long queues were reported outside vaccination sites in the UK and the National Health Service (NHS) website to book the booster shot even crashed on Monday. The NHS returned this week to the highest level of emergency preparedness, which means the response to Omicron will be nationally coordinated.

It won’t stop in the UK

The new variant is still being studied by researchers around the world but reportedly has more mutations than those of the Delta variant and could be more resilient against vaccination. The World Health Organization (WHO) designated Omicron as a variant of concern, the fifth so far to obtain that classification, as countries tighten restrictions. Although it’s still early days, this is by far the most contagious strain of the virus we’ve seen.

Maria van Kerkhove, WHO’s technical manager of the pandemic, told El Pais newspaper that the world is “facing a tsunami of infections” because of the Delta and the Omicron variants. She asked governments not to delay action, suggesting the use of masks, remote working and preparing hospitals but dismissing new quarantines. 

In an initial study, Pfizer and BioNTech, manufacturers of one of the Covid-19 vaccines currently available, found a 25-fold reduction in the neutralization ability of vaccines against the Omicron variant. Nevertheless, the two companies argued an extra boosted shot would provide the sufficient protection to fight the strain of the virus.

Pfizer boosters seem to offer Omicron protection — but two shots may not

Two doses of the Pfizer/BioNTech vaccine may not be enough to protect against the novel Omicron coronavirus variant, but three doses are enough to neutralize it, the pharmaceutical companies said in a statement. This offers new hope to fight the mutant variant which, although has just been discovered, has the entire world on alert.

Image credit: Flickr / The Focal Project.

Pfizer chief executive Albert Bourla said “the best course of action” to prevent the spread of Covid-19 is to get as many people as possible vaccinated with two doses and a booster. It’s not exactly a new approach, but it could be the only way to get some protection against Omicron until (or if) new vaccines arrive. Two doses only offer a limited level of protection against the Omicron variant, with initial data suggesting protection improves with a booster shot, he added.

However, these results are only preliminary and Pfizer says they will continue gathering data and evaluating the “real-world effectiveness” of the vaccine. They are now working on a new vaccine specific for the Omicron variant, which they hope it will be ready for delivery in the next 100 days, following approval from regulatory agencies. 

Initial Omicron studies

Researchers in South Africa first identified the new Omicron variant in late November. Since then, teams have been racing to better understand its properties and the risks it poses. Preliminary data suggests that the variant is highly transmissible (spreading faster than the Delta) and that is can infect people who are immune to other COVID-19 variants. 

The new strain has been classified as a variant of concern by the World Health Organization, the fifth one to be given that category. Still, WHO’s Emergency Director Mike Ryan said earlier this week that there are no signs that Omicron could be better at evading vaccines than other variants, expressing confidence in the vaccines’ overall protection. 

Pfizer and BioNTech found an average 25-fold reduction in the neutralization ability of vaccines against the Omicron variant. This shows that two doses “may not be sufficient to protect against infection with the Omicron variant,” they said — although again, it’s still preliminary data.

Another study by researchers from South Africa also found that the Omicron variant partly escapes antibody neutralization given by the Pfizer vaccine. Nevertheless, the preprint study showed that previously infected and then vaccinated individuals are likely well protected. This would also be the case of those who get a booster shot. 

Health officials are urging people to get vaccinated and boosted as soon as possible. In the US, for example, the Centers for Disease Control and Prevention advise adults who have had the Pfizer and Moderna vaccines to get a booster six months after their second shot. A quarter of those who are vaccinated have received a booster in the US.

“Vaccines remain the best public health measure to protect people from COVID-19, slow transmission, and reduce the likelihood of new variants emerging. COVID-19 vaccines are highly effective at preventing severe illness, hospitalizations, and death. Scientists are currently investigating Omicron, including how protected fully vaccinated people will be,” the CDC wrote in a statement.