The Kent strain of coronavirus does not cause different symptoms or a more severe Covid-19 illness than earlier variants, experts have claimed.
King’s College London researchers say they found ‘no significant difference’ in disease suffered between regions where the variant was widespread in December – London, South East and East of England – compared to those further north, where it was yet to gain a foothold.
This suggests the strain — dubbed B.1.1.7 — may not be more deadly than the original virus and that an alleged higher risk of death could be linked to other factors.
Sir Patrick Vallance sparked a row over the variant in January when he told the public at a Downing Street press conference that it appeared to be more deadly but that there was ‘huge uncertainty’ about it.
Scientists said no proof had been offered that this was the case and the Government’s evidence was not published until hours after the briefing, with it showing there was wide variation in scientists’ estimates of how deadly it is.
Sir Patrick said that data currently suggests the new variant could kill 13 or 14 of every 1,000 men over the age of 60 who caught it, compared to 10 in 1,000 of the old variant.
A top scientific group advising the Government, Nervtag, has said there is a ‘realisitc possibility’ the Kent variant could be more deadly, but this is not confirmed.
There were concerns that it may get around vaccine-triggered immunity but studies have put these to bed and found jabs should be just as effective against it.
Another concerning variant, from South Africa, has also been found to be vulnerable to the antibodies sparked by vaccines but they may be less effective against it. Research is ongoing into variants originating in Brazil but there are not yet suggestions that any of the above are more deadly than the original virus.
The Kent variant is now the dominant variant in the UK and more than 100 cases of the South African strain have been identified here.
Above are the number of hospitalisations by region in England and Wales (left) and the number of symptoms suffered during infections by region (right). Scientists say there was no significant difference between areas with high and low prevalence of the Kent variant, suggesting it does not trigger more severe infections
Data was also collected on the duration of infections in regions with high and low prevalence of the Kent variant. This also indicated no significant differences in disease suffered
Above are the symptoms of the virus from positive tests split by type. The NHS only recognises three signs of coronavirus – high temperature, new continuous cough and loss of taste and smell – but experts say there are 14 key symptoms
Dr Mark Graham, an epidemiologist at King’s College London who led the study, told MailOnline there was still uncertainty around whether the Kent variant is deadlier and more evidence is needed.
‘However, our paper does add to the growing body of evidence that the new variant is more transmissible than the old variant,’ he said.
‘This is actually more worrying than an increase in the new variant’s mortality – because of the exponential nature of spread, a more transmissible variant will lead to a lot more people getting Covid, and thus a lot more people dying.
WHAT ARE THE MOST COMMON SYMPTOMS OF CORONAVIRUS?
Below are the most common symptoms of coronavirus as reported by 4,182 people who tested positive for the disease.
They entered their symptoms into the Covid Symptom Study app.
% of individuals ever experiencing symptom
Loss of smell
Shortness of breath
Severe shortness of breath
‘So an increase in transmissibility of 35 per cent (as suggested in the study) could cause more deaths than an increase in the strain’s deadliness by, say 35 per cent.’
This is because you would expect there to be a proportionate increase in deaths that is in line with how much cases increase by.
For example, with a 0.1 per cent death rate you would expect 10 deaths for every 1,000 cases.
But if there were 1,300 cases – a 30 per cent increase – there would be expected to be 13 deaths – also a 30 per cent increase, up from 10 – even though the variant was no more deadly.
But Dr Graham added they had found the brutal lockdown had curbed the spread of the virus and forced the second wave to shrink, protecting more Britons from the disease.
There had been concern the measures would not be able to block the transmission of the virus because it is more infectious.
Dr Claire Steves, who was involved in the study, said it showed the Kent variant ‘does not appear to alter symptoms, severity or duration of Covid when we take account of the changing seasons and age of people affected’.
She added: ‘It’s important to emphasise the range of symptoms both the new and the old variant can cause, such as headaches and sore throat, in addition to the classic triad of cough, fever and loss of smell.’
The scientists looked at data from 55,000 Brits who had been infected with Covid-19 between September and December for their study.
The cases were extracted from the ZOE Covid Symptom Study App, where users log daily whether they are well and what symptoms they are suffering so scientists can track the pace of the outbreak.
Researchers checked each for 14 symptoms, the total number of symptoms to indicate the severity of the disease and whether warning signs lasted 28 days or more.
They also counted self-reported hospitalisations and possible re-infections, where two separate positive tests were recorded 90 days apart.
These were then split by region and matched against the estimated prevalence of the new variant across each using data from COG-UK genomics, which tests 10 per cent of all swabs to map the spread of new types of the virus.
The data also showed there was ‘no difference’ in the proportion of reinfections and hospitalisations.
As many as 249 suspected reinfections were noted in the study, or 0.7 per cent of the total, which was the same as was expected with the old variant.
Above is the incidence of the old virus and new strains by region (left) and the estimated R rate for those regions by time (right). B.1.1.7 indicates the Kent variant. Scientists say the new variant pushed up the R rate by a third because it is more transmissible
Scientists think the variant is more transmissible because of differences on its spike proteins – which it uses to invade cells
This is yet more evidence the Kent strain cannot get around antibodies triggered by the vaccine or previous immunity.
What do we know about the Kent variant?
Name: B.1.1.7, formerly VUI-202012/01
Where did it come from? The variant was first found in Kent and can be traced back to September 2020. Scientists noticed that it was spreading in November and it was revealed to the public in December.
What makes it new? The variant, which is a version of the SARS-CoV-2 coronavirus that causes Covid-19, has a series of mutations that change the shape of the spike protein on its outside. The main one is known as N501Y. This appears to make it better able to stick to the cells inside the body and makes it more likely to cause infection and faster to spread.
How did that happen? Viruses, particularly ones spreading so fast and in such huge numbers, mutate all the time. To reproduce they basically force living cells to copy and paste the viral genetic code, and this can contain errors that lead to slightly different versions of the virus. Often these mutations make no difference but, if they make the virus stronger, they can stick around for further generations and become the norm.
What can we do about it? Nothing much. People who catch the virus won’t know which type they have, and it will still cause the same symptoms and illness. Officials can try to contain it by locking down the areas where it is most prevalent, but if it is stronger than other versions of the virus it will eventually spread everywhere and become dominant as long as people continue to travel.
Will our vaccines still work? Yes, it’s very likely they will. Scientists on SAGE are fairly sure the mutations the Kent variant carries do not significantly affect how well the immune system can handle it. People who have a vaccine modelled on an older version of the virus, or who have been infected with Covid-19 before, are likely to be immune to it. This is because the main mutations are only on one part of the spike protein, whereas the immune system is able to target various other parts of the virus.
They also found the new strain could push up the reproduction rate (R rate) by a third, because it is more transmissible.
This will trigger more cases of the virus and lead to a higher number of hospitalisations because more people are catching the virus.
The study has been published as a pre-print and is yet to be checked by other scientists.
Professor Tim Spector OBE, an epidemiologist from King’s College London who heads up the ZOE app, said the data was also a promising sign that the strain could not get around immunity triggered by the vaccines.
He said: ‘A key question was whether immunity would be lost with the new strain. Our analysis found that of every 1,000 people previously infected with the virus, only seven got reinfected and this rate was not affected by the new Kent variant.
‘It’s reassuring that reinfections are still really rare many months after previous infection, suggesting that both natural immunity and vaccines will be effective against this new strain.
‘This research highlights the unique value of the ZOE app in understanding the impact of new coronavirus variants across the population in a matter of weeks, and we need our app users to help us maintain vigilance against further new strains as they emerge.’
The NHS only recognises three symptoms of coronavirus, although scientists say there are many others that should be included.
The ZOE team says it has identified 14 others and is calling on the NHS to recognise more so that more infections can be caught in the early stages – limiting the risk of the virus being passed on to others.
It comes after the Government’s top scientific advisers told ministers to ask people to wear masks in crowded outdoor spaces like parks and playgrounds to limit the spread of the Kent variant.
Papers released by Sage, the Scientific Advisory Group on Emergencies, say advice on the use of face coverings should be strengthened so rules are applied more ‘consistently and effectively’ in the fight against the Kent variant of coronavirus.
While shops and offices are strictly enforcing mask wearing already, the document, drawn up on January 13, says people should consider protecting themselves in ‘outdoor spaces where it is difficult to maintain distance’.
The paper, put together by Sage’s Environmental Modelling Group, says that risks of infection are very high in ‘semi-enclosed spaces’ such as ‘covered seating areas, transport shelters or street market stalls’.
The call to strengthen rules around face covering hopes to prevent the spread of the Kent variant, which may be up to 70 per cent more infectious.
A SAGE paper that followed Sir Patrick Vallance’s warning that the variant is more deadly cited three studies: A London School of Hygiene and Tropical Medicine study (left) based on 2,583 deaths that said the hazard of death within 28 days of test for the mutant strain compared with non-mutant strains was 35% times higher An Imperial College London study (centre) of the Case Fatality Rate of the new mutant strain that found the risk of death was 36% times higher A University of Exeter study (right) that suggested the risk of death could be 91% higher. Both the Exeter and the Imperial studies were based on just 8% of deaths during the study period
People infected with Kent coronavirus variant are MORE likely to get symptoms
People infected with the Kent coronavirus variant are more likely to get symptoms than those who have caught older strains but are less likely to lose their smell and taste, according to the Office for National Statistics.
Data from the ONS revealed today that 53 per cent of people in England who tested positive with the variant reported Covid-19 symptoms such as cough, fatigue and fever, compared to 48 per cent of people with other variants.
The ONS found that the largest differences in reported symptoms between the new variant and older stains were cough, sore throat, fatigue and muscle aches, which all became more common with the new variant.
But on the other hand the loss of taste and smell, considered to be one of the tell-tale signs of the virus, became less common.
The ONS report found that there was no significant difference in people experiencing shortness of breath, nausea vomiting or headaches between people who had tested positive with the mutation or novel strain.
Figures showed that 19 per cent of those who tested positive with the UK variant had a loss of smell and taste in comparison to other strains, among which it was 22 per cent.
The Government last week revealed that scientists think the Kent variant may be more deadlier than the previous dominant version of the virus, and it is already known to be more infectious by around 30 to 70 per cent.
The Kent strain now makes up around 60 per cent of all cases in England, according to separate ONS testing figures.