A coronavirus variant first detected in South Africa 'could be more infectious' than other mutations and have the potential to 'evade vaccines', scientists have said.
The C.1.2 strain, which is linked to 'increased transmissibility', is more mutations away from the original virus seen in Wuhan, experts at South Africa's National Institute for Communicable Diseases and the KwaZulu-Natal Research Innovation and Sequencing Platform said.
The virus was first identified by scientists in South Africa in May and has since been found in England, China, the Democratic Republic of the Congo, Mauritius, New Zealand, Portugal and Switzerland.
In their study scientists found the strain, which descends from the C.1 strain that was first spotted amid the first wave of the pandemic, has a mutation rate of about 41.8 mutations per year.
The C.1.2 strain, which descends from the C.1 strain that was first spotted amid the first wave of the pandemic, has a mutation rate of about 41.8 mutations per year
This rate is nearly double the current global mutation rate seen in any other Variant of Concern (VOC) so far.
During their study, researchers found a monthly increase in the number of C.1.2 genomes in South Africa, rising from 0.2 per cent in May to 1.6 per cent in June and 2.0 per cent in July.
This short period of consistent increase has also been spotted in the Alpha, Beta and Gamma variants.
Scientists also found 14 mutations in nearly 50 per cent of the variants which had a C.1.2 sequence.
While more research is required 'to determine the functional impact of these mutations', scientists warned the latest variant, which has 'mutated substantially', could help the virus evade antibodies and immune responses. In their report, which was published in the journal Nature, the scientists said: 'We describe and characterise a newly identified SARS-CoV-2 lineage with several spike mutations that is likely to have emerged in a major metropolitan area in South Africa after the first wave of the epidemic, and then to have spread to multiple locations within two neighbouring provinces.
'We show that this lineage has rapidly expanded and become dominant in three provinces, at the same time as there has been a rapid resurgence in infections.
'Although the full import of the mutations is not yet clear, the genomic and epidemiological data suggest that this variant has a selective advantage—from increased transmissibility, immune escape or both.
'These data highlight the urgent need to refocus the public health response in South Africa on driving transmission down to low levels, not only to reduce hospitalisations and deaths but also to limit the spread of this lineage and the further evolution of the virus.'
Earlier this month, a report published by Public Health England said that the C.1.2 strain was among ten variants being monitored by scientists in the UK.
In April, scientists found another South African strain — called B.1.351 — had the potential to 'break through' the Pfizer jab. Scientists examined 400 people who had tested positive for coronavirus at least 14 days after receiving one or two doses of the jab - and 400 who tested positive with no vaccine.
The variant was eight times more prevalent in those who had two jabs than none. It was seen in 5.4 per cent of people with two doses - but 0.7 per cent of people without any.
Scientists working on the Tel Aviv University study said their results suggested the vaccine is less effective against the South African variant - compared with the original coronavirus and the Kent variant.
The B.1.351 has key mutations on its spike protein which scientists fear might make it difficult for the immune system to recognise.
These alterations open the door to it being resistant to vaccines, which train the body to spot the spike protein, or natural immunity from previous infection.
Last month health chiefs spotted another Covid variant spreading in Britain, with 31 mutant strains now on the UK's watchlist.
Sixteen cases of the B.1.621 version of the virus – which is thought to have originated in Colombia – were detected by experts.
Public Health England insisted there was no proof it is deadlier than Delta, which makes up 99 per cent of all cases in the UK.
And they also said there was no evidence that the strain renders any of the vaccines currently deployed any less effective.
The latest study comes as Britain recorded a further 61 Covid deaths and 33,196 more new cases on Sunday, official data showed.
The number of new cases represents a 3 per cent rise on the new daily cases from last Sunday which stood at 32,253 while only 49 daily deaths were recorded.
Infections in the last seven days rose by 5.8 per cent on the week before, and weekly deaths jumped by 16 per cent.
This means the new positive test rate over the last seven days is 240,528 while the number of deaths within 28 days of a positive test has been recorded as 797 - an increase of 110.
The Sunday figure for fatalities tends to be lower than weekdays due to a delay by some hospitals in reporting deaths.
Britain is currently recording about 30,000 Covid cases a day, which SAGE scientists fear will surge when pupils go back to classrooms next week. This time last year there were nearly 2,000 cases a day.
Delta Covid variant is twice as likely to land patients in hospital, study shows
The Delta variant doubles the risk of hospital admission, a study has found.
It was already known that the Covid strain first identified in India is up to 50 per cent more transmissible than the previous dominant Alpha variant, which emerged in Kent.
But the largest study to date comparing the two now shows those infected with the Delta strain are 2.26 times more likely to be admitted to hospital.
Delta is also 1.45 times more likely to see people entering A&E needing emergency treatment.
Scientists claimed this is more proof that the same traits which make the variant spread faster also increase levels of the virus in those it infects, which results in them becoming more severely ill.
The authors of the study, led by Public Health England and Cambridge University, said their results should be used by hospitals to plan – especially in areas where the Delta variant is on the rise.
Dr Anne Presanis, a senior statistician at the university, said: 'Our analysis highlights that in the absence of vaccination, any Delta outbreaks will impose a greater burden on healthcare than an Alpha epidemic.
'Getting fully vaccinated is crucial for reducing an individual's risk of symptomatic infection with Delta in the first place and, importantly, of reducing a Delta patient's risk of severe illness and hospital admission.'
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