WHO officially notified the four variants of the new coronavirus

31 December 2020 local time, WHO officially notified the major variants of the new coronavirus since its inception, including four variants.
from late January to early February 2020, the new coronavirus developed a D614G mutation, which gradually replaced the originally discovered strain. By June 2020, the variant will be the leading new coronavirus type to spread worldwide. Studies have shown that the variant is more infectious and propagated than the initial strain, but does not cause more serious diseases and does not affect the effectiveness of existing diagnostic, therapeutic, vaccine and public health measures.
August-September 2020, a new coronavirus variant associated with otters was discovered in Denmark, named Cluster 5 by the Danish authorities, with a variant that had not previously been observed. According to preliminary studies conducted in Denmark, it is worrying that the variant may reduce the scope and duration of immune protection resulting from natural infection or vaccination, and assessments are still ongoing. Denmark has so far found only 12 cases of human infection with this variant in September, and the variant does not appear to have spread widely.
14 December 2020, the UK reported to WHO a new coronavirus variant named VOC 202012/01, which first appeared in the south-east of England. Preliminary epidemiological studies have shown that the variant is more propagative, but the severity of the disease (assessed in terms of length of stay and 28 days of mortality) and re-infection have not changed and most diagnostic tools are not affected. As of 30 December, the variant had been found in 31 other countries and territories in five of WHO's six regions.
December 18, 2020, South Africa detected a new coronavirus variant, the N501Y mutation, which South Africa named the 501Y.V2 variant, which is spreading rapidly in three South African provinces. Although the new coronavirus has also had an N501Y mutation previously found in the UK, analysis suggests it is a different variant from the mutated new coronavirus found in South Africa. In the week after 16 November, South African health authorities found in routine genetic sequencing that the variant had largely replaced other new coronavirus transmitted in the Eastern Cape, Western Cape and KwaZulu-Natal provinces. Preliminary studies suggest that the variant is associated with higher viral loads and may increase infectiousness, but there is no evidence that it causes more serious diseases. Further investigation is needed to understand the effects of this variant on virus transmission, diagnosis, vaccines, etc. As of 30 December, the variant had been discovered in four countries other than South Africa.
WHO says epidemiological and virological investigations are under way in countries affected by the mutated new coronavirus to understand its prevalence, and genetic data on the mutated new coronavirus found in the UK and South Africa have been shared. WHO also notes that all viruses, including the new coronavirus, change over time, and that most mutations do not lead to increased virus transmission and sometimes limit its spread. As the frequency of infection increases in humans and animals, so do the likelihood of virus mutations.
WHO also stressed that while preliminary assessments showed that the new coronavirus mutated virus found in the UK and South Africa did not increase the severity of the disease, it would lead to higher morbidity and lead to more hospitalizations and deaths, so stricter public health measures were needed to control the spread of the mutant virus. WHO also recommends that countries increase routine genetic sequencing of new coronavirus to better understand the spread of the virus and monitor variants. (Chief Station Reporter Zhu He)