WHO: 4 types of coronavirus variants circulating

The WHO has said that  at least four types of coronavirus variants are circulating the globe since the first case of the infection was reported in Wuhan, China way back in November 2019. In its report the WHO said since the start of the pandemic, the UN health agency has received several reports of unusual public health events that are possibly due to the variants of SARS-CoV-2.

A variant of SARS-CoV-2 with a D614G substitution in the gene encoding the spike protein emerged in late January or early February 2020. Over a period of several months, the D614G mutation replaced the initial SARS-CoV-2 strain that was identified in China. By June 2020, the WHO said, the mutation became a more dominant form of the coronavirus circulating globally, the report said. After the second variant was reported, another variant of the coronavirus was reported in August and September 2020 which was linked to infection among farmed mink that subsequently transmitted to humans. The fresh coronavirus variant, referred to as the "Cluster 5", was identified in North Jutland, Denmark. In September 2020, the authorities identified only 12 human cases of the Cluster 5 variant.

On December 14, 2020, the UK government reported a variant, referred to as SARS-CoV-2 VOC 202012/01. Interestingly, the variant was not phylogenetically related to the SARS-CoV-2 virus which has been circulating in the UK at the time the variant was detected. It remains unclear how and where SARS-CoV-2 VOC 202012/01 has originated. the report said.

On December 18, South Africa announced the detection of a new variant of SARS-CoV-2 that is rapidly spreading in three provinces of the country. South Africa has named this variant 501Y.V2. By December 30, VOC-202012/01 variant has been reported in 31 other countries/territories/areas in five of the six WHO regions. The variant which was reported in South Africa has been reported from four other countries to date.

"While SARS-CoV-2 VOC 202012/01 from the UK also has the N501Y mutation, phylogenetic analysis has shown that 501Y.V2 from South Africa are different virus variants. In the week beginning 16 November, routine sequencing by South African health authorities found that this new SARS-CoV-2 variant has largely replaced other SARS-CoV-2 viruses circulating in the Eastern Cape, Western Cape, and KwaZulu-Natal provinces," the WHO report said.