Health

Super-infectious Kent Covid strain has spread to at least 60 countries

The super-infectious mutant strain of coronavirus that was first detected in Kent has spread to at least 60 other countries, the World Health Organization said today.

Cases of the B.1.1.7 variant, sometimes known as VOC 202012/01, have been reported in most of continental Europe, as well as in nations further afield including the US, Australia, India, China and Saudi Arabia. 

The WHO revealed the strain, which is thought to be 50 per cent more infectious than the original Covid variant, was detected in 10 new countries in the past week alone.

On Monday the Centers for Disease Control and Prevention said at least 122 cases had been identified in 20 US states, with the bulk being picked up in Florida and California.  

There will be far more infections across the US, however, because the CDC only analyses a small percentage of random samples from positive tests. American officials now anticipate the Kent strain will experience ‘rapid growth’ over the next few weeks and become the dominant Covid variant nationwide by March.

The Kent strain first emerged in the South East of England in October and has quickly become the dominant strain in Britain, sparking a devastating winter wave of infections and hospital admissions which plunged the country into a third lockdown.

Studies have shown the Kent strain is between 50 and 70 per cent more infectious than the original version thanks to key mutations on its spike protein which make it easier to lock onto human cells. This gives it an evolutionary edge over other strains.

There were also fears that these same mutations could make the variant resistant to vaccines or natural immunity from previous infection. But early data from UK studies suggest this won’t be the case.

Cases of the B.1.1.7 variant, sometimes known as VOC 202012/01, have been reported in most of continental Europe, as well as in nations further afield including the US, Australia, India, China and Saudi Arabia (shown in orange and in grey)

Studies have shown the Kent strain is between 50 and 70 per cent more infectious than the original version thanks to key mutations on its spike protein which make it easier to lock onto human cells. This gives it an evolutionary edge over other strains

Studies have shown the Kent strain is between 50 and 70 per cent more infectious than the original version thanks to key mutations on its spike protein which make it easier to lock onto human cells. This gives it an evolutionary edge over other strains  

Offering hope that Britain’s inoculation drive won’t be in vain, Sir Patrick Vallance – chief scientific adviser to the UK Government – today insisted that the current crop of Covid-19 vaccines should work against the Kent strain.

But he admitted there were still ‘question marks’ over the variants first found in South Africa and Brazil, which are thought to be even more infectious than the Kent one and have more problematic mutations. 

The vaccines being rolled out now are based on versions of the constantly-evolving virus studied a year ago, so may become less effective as more mutations occur over time.

Moderna said it was confident its jab will work against the England and South Africa variants and it will carry out more tests on the Brazilian one. Oxford University said it was running checks on its own jab.

Mutant strain of coronavirus has been in the US since November 6 – six weeks BEFORE the UK flagged it as a ‘variant of concern’, study finds 

The highly-infectious coronavirus variant B.1.1.7 which emerged in Kent in September 2020 had reached the US by November 6, new research shows.

It is thought to have mutated inside a single patient in England struggling with a critical case of Covid-19 which forced the virus to adapt, changing its genetic code. 

University of Arizona researchers studied the genomes of 50 B.1.1.7 infections in the US and traced their lineage to determine when the mutated variant first appeared in the US. 

They found two clusters of infections, one in California and one in Florida, which originated on November 6 and November 23 respectively – the first being roughly six weeks before SAGE told the government about the new variant and health secretary Matt Hancock announced it to the public. 

This retrospective study has the benefit of genomic analysis and hindsight, and the first actual case of the Kent strain was not diagnosed in an American until December 29. 

‘It is striking that this lineage may already have been established in the US for some 5-6 weeks before B.1.1.7 was first identified as a variant of concern in the UK in mid-December,’ the researchers write. 

‘And it may have been circulating in the US for close to two months before it was first detected, on 29 December 2020.’

The study has not yet been peer-reviewed but is available online as a pre-print.  

The exact origin of the Kent variant is unknown but it is believed it sprung up in mid-September. 

Dr Susan Hopkins, a senior Public Health England (PHE) official said in December that originally there was ‘nothing to particularly highlight that this was something of major concern, as variants come and go’.

Mutations in viruses occur all the time, with the vast majority of them being harmless or deleterious to the pathogen.

However, by chance, sometimes the tweaks to the viral code give it a survival edge and increase its success, often by becoming more infectious and easier to spread. 

This is what is thought to have occurred in the B.1.1.7 variant, which previous studies have found is more abundant in the upper respiratory tract. 

A mutation on the spike protein — which protrudes from the coronavirus and hijacks human cells — made it better at infecting people. 

This so-called N501Y mutation is also found on the South African and Brazilian variants which have since been identified. 

The Arizona-based researchers found all the California cases share another minor mutation, which is seen in just 1.2 per cent of European B.1.1.7 cases.

This, they say, indicates a single introductory event, likely from international travel, seeded the variant in California where it then spread from person to person.  

A similar trend was seen for the Floridian batch of cases, which were very similar to the most common type of B.1.1.7 seen in the UK. 

This is a ‘strong indication that they too descend from a single introduction event’, the scientists say. 

Pfizer today said the it was ‘unlikely’ that the B.1.1.7 lineage — the Kent variant — will evade the vaccine. Studies of a lab-made version of the variant was neutralised by antibodies created by the jab. 

The major concerns about the Kent, South Africa and Brazil variants of the virus are that they are now widespread and significantly different to earlier versions, to which many people have developed immunity.

Kent’s variant is the one least likely to drive down the efficacy of a vaccine because it is missing a mutation found on the other two.

The Brazilian and South African variants share a mutation called E484K, which is thought to change the shape of the spike protein on the outside of the virus so much that immune system antibodies in many people are unable to recognise it.

Researchers have not yet done tests on how the immune system of someone who has had a Covid vaccine would respond to those versions of the virus.

When asked about variants and vaccines in a television Q&A on Sky News this morning, Sir Patrick said: ‘On the variant that was first identified in Kent, I think we’re increasingly of the view that that variant will be susceptible to the vaccine and to previous immunity. 

‘The studies are all pointing in that direction so I think that’s good in terms of vaccine effect.

‘For some of the others that are popping up around the world – and they will continue to pop up – we’ve still got some question marks as to how effective a vaccine will be. 

‘Those studies need to be continued and I think it’s likely that we will need to have modified vaccines in due course.’

The reason new variants may be able to get past the immune system is that the substances the body makes to tackle viruses are extremely specific and fit to the virus like a key in a lock.

These substances, the main type of which are antibodies, can be made by someone catching the virus for real or being injected with a vaccine.

If the virus changes shape too much – and it is constantly changing because of random errors when it reproduces, even though many of these changes make no difference – the immune system won’t be able to attach to it.

Companies and scientists making the current crop of vaccines insist that their vaccines will still work as intended, at least on the Kent variant also known as B.1.1.7.   

Pfizer and BioNTech scientists yesterday published a paper that said it was ‘unlikely that the B.1.1.7 lineage will escape [vaccine]-mediated protection’.

The team exposed the virus to the blood of 16 people who had been enrolled in trials of the companies’ vaccine to see if the immune cells would recognise and destroy it.

When they compared the immune reaction to this Kent variant with the reaction to the original virus from Wuhan they said there was ‘no biologically significant difference in neutralization activity’.

Moderna said in a statement: ‘The Moderna Covid-19 Vaccine expresses the full-length spike protein of the SARS-CoV-2 virus, allowing for the generation of neutralizing antibody responses to multiple domains of the protein. 

‘The full-length Spike protein is 1,273 amino acids long, so while recent variants involve multiple mutations, for instance up to eight amino acid changes in the spike protein of the B.1.1.7 strain, these represent less than a one per cent difference from the spike protein encoded by Moderna’s vaccine.

‘While we plan to run tests to confirm the activity of the vaccine against any strain, the broad range of potential neutralizing antibodies made possible by the Moderna Covid-19 Vaccine provide confidence that our vaccine will also be effective at inducing neutralizing antibodies against them.’ 

An AstraZeneca spokesperson said: ‘The University of Oxford and labs across the world are carefully assessing the impact of new variants on vaccine effectiveness, and starting the processes needed for rapid development of adjusted Covid-19 vaccines if these should be necessary.’ 

While the claim that Pfizer’s jab will still work against the variant is good news for Britain, where it is now the dominant strain, it is also good for the US, which has seen it spread widely with research now suggesting it has been there since November.

Coronavirus variant found in Germany

Another mutated coronavirus variant has been found in Germany, different to those originating in the UK, South Africa and Brazil.

Health officials said the variant was identified in Bavarian hospital patients, but it isn’t yet known how transmissible it is or whether it makes Covid worse.

Concerns have grown in recent weeks over the spread of the variants, the UK-based version of which forced Boris Johnson to cancel Christmas for millions and plunge the nation into a third national lockdown

Discovery of the new German strain has also seen Angela Merkel take action, with the Chancellor declaring restrictions including the closure of schools and shops will be extended until mid-February.

Germany’s infection rate has stabilised in recent days, indicating that existing restrictions may have been effective in bringing down the numbers. 

The variant was found in 35 out of 73 newly infected people at Garmisch-Partenkirchen, in the southeast of the country.

Experts continue to analyse samples after Clemens Stockklausner, deputy medical director at the Charité university hospital in Berlin, admitted it was too early to say whether this virus was more deadly than other variants.

He said: ‘At the moment we have discovered a small point mutation… and it is absolutely not clear whether it will be of clinical relevance.

‘We have to wait for the complete sequencing.’ 

University of Arizona researchers studied the genomes of 50 B.1.1.7 infections in the US and traced their lineage to determine when the mutated variant first appeared in the US. 

They found two clusters of infections, one in California and one in Florida, which originated on November 6 and November 23 respectively – the first being roughly six weeks before SAGE told the government about the new variant and health secretary Matt Hancock announced it to the public. 

This retrospective study has the benefit of genomic analysis and hindsight, and the first actual case of the Kent strain was not diagnosed in an American until December 29. 

‘It is striking that this lineage may already have been established in the US for some 5-6 weeks before B.1.1.7 was first identified as a variant of concern in the UK in mid-December,’ the researchers write. 

‘And it may have been circulating in the US for close to two months before it was first detected, on 29 December 2020.’

Greater concern about the effectiveness of vaccines is swirling around mutations that emerged in South Africa and Brazil, which carry an extra mutation called E484K.

This mutation has been linked in early scientific studies to ‘immune escape’ and may make the antibodies of some people significantly less effective at destroying it.

South African academics found that 48 per cent of blood samples from people who had been infected in the past did not show an immune response to the new variant. 

Professor Penny Moore, the researcher behind the project, claimed people who were sicker with coronavirus the first time and had a stronger immune response appeared less likely to get reinfected.

She told a scientific panel meeting earlier this week: ‘When you test the blood of people infected in the first wave and you ask “Do those antibodies in that blood recognise the new virus?” you find that in 50 per cent of cases – nearly half of cases – there’s no longer any recognition of the new variant.

‘In the other half of those individuals, however, there is some recognition that remains. I should add those are normally people who were incredibly ill, hospitalised and mounted a very robust response to the virus.’

Professor Moore said that research made it ‘clear that we do have a problem’, but that it is still in its early stages and laboratory studies cannot perfectly recreate the real world.

On whether vaccines would be affected, she added: ‘If you have very high antibodies to begin with, there does remain some recognition of the new virus and that’s important as we think about vaccines.

‘Some vaccines elicit very high levels of antibodies and others do not, so we need to understand whether there is some recognition by vaccine-elicited, rather than infection-elicited, antibodies.’

The inevitable mutation of the virus could mean that vaccines have to be updated, redeveloped and given out every year in the same way that flu jabs are.

Sir Patrick said: ‘I think that will be something that’s going to be a regular feature of this.

‘Fortunately the new vaccine technology, particularly the messenger RNA vaccines [Pfizer and Moderna], are relatively easier to change and you can almost dial up a change. It then takes a few weeks for that to be made and come through, so it’s not instantaneous, but I think that’s what’s going to come through.

‘I wouldn’t be at all surprised if, from time to time, we need to get slight variations of the vaccine in order to make sure we keep on top of this, and I think changes in the virus will occur all over the world. 

‘Viruses mutate, that’s what they do, and I would expect to see more and more of that as we go forward.’


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