The World Health Organization (WHO) said at least four types of coronavirus variants are circulating the globe since the first case of the coronavirus infection was reported in China's Wuhan in November 2019.
The World Health Organization (WHO) has said in a report 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. 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.
The WHO said 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.
Studies have indicated that the second strain with the D614G substitution has increased infectivity and transmission compared to the initial virus strain. The mutation, however, "does not cause more severe illness or alter the effectiveness of existing laboratory diagnostics, therapeutics, vaccines, or public health preventive measures".
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.
"Due preliminary studies conducted in Denmark, there is concern that this variant has may result in reduced virus neutralization in humans, which could potentially decrease the extent and duration of immune protection following natural infection or vaccination," the WHO report said.
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