The Indian variant - officially known as B.1.617 - was initially detected in India in October and has since been found in 17 countries. But, sample testing is not widespread enough to determine how quickly it is spreading. The Indian strain has been called a Double Mutant because of the presence of two variations in the virus's genome, called E484Q and L452R. They impact a portion of the spike protein, that helps the virus enter the host cells. ‘Double Mutant’ might not be technically accurate because the variant contains many different mutations. ‘Double’ in popular terminology refers to these two mutations that have been observed in other strains to increase transmissibility and evade some of the immune protection some people have from Covid-19 infections. Much of the data around the Indian variant is incomplete since very few samples have been shared - 298 in India and 656 worldwide as compared to 384,000 instances of the UK variant. India has been reporting over 200,000 Covid cases daily since 15 April - well beyond its peak of 93,000 cases a day last year. But, the devastating second wave of cases in India could have been caused by large gatherings, and lack of preventive measures such as mask-wearing and social distancing. Another reason can be the combination of immunity waning from the first wave combined with a variant that’s more transmissible leading to more infections. “The combination of the two mutations give a value of 4, in other words, the two mutations do not confer substantial antibody evasion and we can stop using the term 'Double Mutant'” - Ravi Gupta, Professor of Clinical Microbiology, Department of Medicine, University of Cambridge. Genomic sequencing that can identify new strains and track their progress is still relatively sparse in India, where only about 11,000 viruses have been analysed. So, lockdowns are necessary till the numbers are contained.

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