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More recently, strains have appeared in South Africa and the UK, which has raised concerns about the effectiveness of coronavirus vaccines. There is also a suspected new strain in the United States, with the White House Coronavirus Task Force warning at the start of the new year that there may be a new, more transmissible variant of the virus that has evolved in the United States. and that causes the spread, according to a document obtained by NBC News.
And on Sunday, Japan’s National Institute of Infectious Diseases said it had detected a new variant of the coronavirus in four travelers from Brazil.
Essentially, scientists are worried about any major changes in the virus’s so-called spike protein. This contains the receptor binding domain and is used by the virus to enter cells in the body.
As such, mutations can not only make the virus more transmissible, but they can also mean that vaccines are made less potent and require updating.
The “British variant”
The variant was first detected in a patient in Kent, south-east England, in September. It then quickly spread to London. With infections soaring in both regions, an initial analysis suggested it could be up to 70% more transmissible than the older variant circulating in the country.
News of the new variant prompted many countries to ban flights from the UK in an effort to ward off the new strain and led the country’s government to drop a planned easing of social restrictions on Christmas. Nonetheless, the mutation has caused a huge surge in infections, with the number of new daily cases exceeding 50,000 since December 28.
WHO notes that “how and where SARS-CoV-2 VOC 202012/01 originated is not clear,” although scientists are investigating whether the mutation has appeared in patients with weaker immune systems and who had long-lasting coronavirus infections, giving the virus the opportunity and time to evolve in a way that allows it to spread faster.
The “South African variant”
South Africa named the variant “501Y.V2” because of the N501Y mutation found in the spike protein. This mutation, among others, has also been found in the new British strain and as such is believed to be more transmissible as well.
The South African strain contains other mutations, and these have raised concerns that it may prove to be more resistant to coronavirus vaccines. However, most scientists expect the vaccines to work despite the mutation, and the vaccines are regularly adapted to new strains of viruses, such as the common flu.
The “Danish mink variant”
The new strain was found in North Jutland in Denmark and has been linked to infections in farmed mink which were later transmitted to humans.
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Studies are underway to assess the effectiveness of treatment in humans with this variant. Fortunately, it doesn’t appear to be more transmissible, according to the European Center for Disease Prevention and Control and the WHO. Denmark has taken drastic measures by slaughtering 17 million farmed mink.
Early mutation in China
After several months, this became the dominant strain of the virus we know of today, the WHO said. “Over a period of several months, the D614G mutation replaced the original strain of SARS-CoV-2 identified in China and in June 2020 became the dominant form of the virus circulating around the world. ”
Studies in human respiratory cells and animal models have shown that, compared to the original viral strain, the new strain has increased in infectivity and transmission. However, the new variant was not considered to cause “more serious disease or impair the effectiveness of existing laboratory diagnostics, therapies, vaccines or preventive public health measures”.
No blame game
Likewise, US President Donald Trump has been criticized for calling Covid-19 a ‘Chinese virus’ – the coronavirus may have emerged in China, but we still don’t know its origins and a team of WHO experts are coming together. travels to China this week to investigate. At the moment, scientists mostly believe that the virus was transmitted to humans by an animal species, possibly by bats.
Many countries where variants have been discovered – including the UK, Denmark and South Africa – are renowned for their regular surveillance and sequencing of the virus’s genetic code, and are therefore at the forefront. the discovery of mutations. The WHO and other public agencies such as the US Centers for Disease Control and Prevention and the EU ECDC are kept up to date by scientists around the world as major variants emerge.