The World Health Organisation on Monday classified a coronavirus variant first identified in India as a “global variant of concern”. This variant called B.1.617 was classified as a variant under investigation (VUI) by authorities in the UK earlier in May. It has already spread to more than 17 countries and several countries have put travel restrictions for passengers coming from India as a result of the surge in cases here.
The WHO says that a variant of interest (VOI) becomes a variant of concern (VOC) if, through a comparative assessment, it has been demonstrated to be associated with increase in transmissibility or detrimental change in COVID-19 epidemiology, increase in virulence or change in clinical disease presentation or a decrease in effectiveness of public health and social measures or available diagnostics, vaccines, therapeutics. Alternatively, a variant may be classified as a VOC by the WHO in consultation with the WHO SARS-CoV-2 Virus Evolution Working Group.