Indian, global Covid-19 clade 70% same, 1 vaccine may work: CCMB

HYDERABAD: In a development that could result in the use of a common vaccine or drug to fight the novel coronavirus, city-based scientists said the clade or genetic group circulating in India has 70% similarity with the major strain around the world.

Viruses have different clades and they need different vaccines or drugs to target them. If the clade is common, then one vaccine or drug is sufficient to fight it. The clade that is now dominant in India is A2a, which has a similarity with 70% of genomes studied worldwide. The earlier dominant clade in India, A3i, has waned, resulting in the increase of A2a genetic group of the pandemic virus.

According to scientists of the city-based Centre for Cellular and Molecular Biology (CCMB), who analysed the genomes of the novel coronavirus, the similarity in viral genome globally means a vaccine or a drug targeting the mutation in A2a clade will work with the same effectiveness all over the world

No evidence of more severe forms: CCMB

At present about 70% of all Indian as well as global SARS-CoV-2 (novel coronavirus) genomes fall into this clade (A2a). As expected for a strain which is more infectious, A2a clade quickly became dominant in India just like everywhere else,” said CCMB director Dr Rakesh K Mishra.

Mishra, who is a co-author of the CCMB study, however, said there was no evidence to state that this mutation is clinically a more difficult one. “No clade at present has been conclusively shown to be associated with a more severe form of Covid-19 or an increased risk of death,” he said.

The findings of the study, carried out with scientists from Institute of Integrative Biology as collaborators, are now peer-reviewed and published in the journal Open Forum Infectious Diseases published by the Oxford University Press.

CCMB team had analysed more than 2,000 SARSCoV-2 genomes from India available in the public domain to understand the various strains in circulation.

Earlier in June, the team had revealed the presence of a distinct virus population among Indians. This was named the clade I/A3i and is recognised by the presence of four specific variations in their genetic makeup.