All major virus mutations we know

Viruses are constantly mutating, so it’s not surprising that the coronavirus that emerged in China at the end of 2019 has gone through several minor variations. But it has also undergone several major mutations and more significant variations are likely to emerge.

Strains have recently surfaced in South Africa and the UK that have raised some concern about the efficacy of coronavirus vaccines. There is also a suspected new strain in the US, with the White House coronavirus task force warning early in the new year that there could be a new, more communicable variant of the virus that has evolved in the US and is causing spread, according to a document obtained by NBC News.

And on Sunday, Japan’s National Institute of Infectious Diseases said it had discovered a new variant of the coronavirus in four travelers arriving from Brazil.

Essentially, scientists are concerned about any major changes to the virus’s so-called spike protein. This contains the receptor binding domain and is used by the virus to access cells in the body.

As such, mutations can not only make the virus more transmissible, they can also mean that vaccines become less potent and need to be updated.

A new variant was reported by UK health officials to the World Health Organization on December 14, now formally known as “VOC 202012/01” (which stands for “variant of concern, year 2020, month 12, variant 01”).

The variant was first discovered in September in a patient in Kent, South East England. It then quickly spread to London. With infections on the rise in both regions, an early analysis suggests it is up to 70% more transmissible than the old variety circulating in the country.

News of the new variant prompted many countries to ban flights from the UK in an attempt to keep the new tension at bay, and prompted the country’s government to scrap a planned relaxation of social restrictions at Christmas. Nevertheless, the mutation caused a massive increase in infections, with the number of new daily cases exceeding 50,000 since December 28.

The WHO notes that “how and where SARS-CoV-2 VOC 202012/01 originated is unclear,” although scientists are investigating whether the mutation showed up in patients with weaker immune systems who had long-term coronavirus infections, giving the virus the chance and time to evolve in a way that will allow it to spread faster.

Following news from the UK, South African authorities announced on December 18 the discovery of a mutation that was rapidly spreading in Eastern Cape, Western Cape and KwaZulu-Natal. It has now become the dominant strain of the coronavirus in the country.

South Africa named the variant “501Y.V2” because of the N501Y mutation found in the spike protein. This mutation was also found in the new British strain, among others, and as such is believed to be similarly more transmissible.

The South African strain contains other mutations, and these have given rise to some concern that it could prove more resistant to coronavirus vaccines. However, most scientists expect the vaccines to work despite the mutation, and vaccines are regularly adapted to new viruses, such as the common flu.

Another coronavirus variant that surfaced in Denmark last summer was related to the country’s large mink farming. As of June, 214 cases of Covid-19 in humans have been identified in Denmark with variants associated with farmed mink. Twelve of those cases were identified as a unique variant that was reported to WHO on Nov. 5.

The new strain was found in Northern Jutland, Denmark, and has been associated with infections in farmed minks that were subsequently passed on to humans.

“The variant, referred to as the ‘Cluster 5’ variant by the Danish authorities, had a combination of mutations that had not been previously observed,” noted the WHO. It added that these raised concerns that they “could result in decreased virus neutralization in humans, potentially reducing the extension and duration of immune protection after natural infection or vaccination”.

Studies are underway to assess the effectiveness of the treatment in people with this variant. Fortunately, it no longer appears to be transferable, according to the European Center for Disease Prevention and Control and WHO. Denmark took drastic measures by killing 17 million farmed minks.

The WHO notes that a variant of the coronavirus emerged early in the pandemic (indeed, before it was even declared a global pandemic in March 2020), noting that a new strain with a mutation known as “D614G” emerged in late January . Or early February 2020.

After several months, this became the dominant strain of the virus we know today, WHO said. “Over a period of several months, the D614G mutation replaced the original SARS-CoV-2 strain identified in China and became the dominant form of the virus circulating worldwide by June 2020.”

Studies with human respiratory cells and animal models showed that compared to the original virus strain, the newer strain increased in infectivity and transmission. However, the new variant was not seen as a “more serious disease or an alteration of the effectiveness of existing laboratory diagnostics, therapies, vaccines or public health preventive measures”.

While variants are sometimes referred to as “the British strain” or “mutation in Denmark,” experts say it is important to note that the origin of these viruses is ultimately difficult to prove and countries should not be “blamed” for various mutations. .

Likewise, US President Donald Trump has been criticized for calling Covid-19 ‘the Chinese virus’ – the coronavirus may have surfaced in China, but we still don’t know where it’s coming from and a team of WHO experts are traveling to China this week to investigate. For now, scientists usually believe the virus was transmitted to humans by a species of animal, possibly bats.

Many countries where variants have been discovered – including the UK, Denmark and South Africa – are known for their regular monitoring and sequencing of the virus’s genetic code, and are therefore at the forefront of mutation discovery. WHO and other public authorities, such as the US Centers for Disease Control and Prevention and the EU’s ECDC, are kept informed by scientists around the world when major variants emerge.