The proportion of the U.K. variant (B.1.1.7) in genome samples sequenced from COVID cases in Delhi has risen from 28% in the second week of March to the 50% in the last week, Dr. Sujeet Singh, Director, National Centre for Disease Control (NCDC) said in a webinar on Friday.
The U.K. variant has a mutation N501Y that is reported to increase the transmission of the virus leading to more numbers and a knock-on consequence of increasing disease severity and mortality.
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Speaking at the webinar organised by the Department of Biotechnology, Dr. Singh said there was also a rise in the Indian variant (B.1.617), that has two mutations associated with increased efficacy and decreasing the potency of vaccines.
However while the relative proportion of known variants of concern, or VoC, (the U.K., South Africa, Brazil variants) is around 11%, investigations were still on to determine to what extent they were responsible for the severity of disease. New Delhi is undergoing an unprecedented surge in it fourth wave with a rise in instances of people manifesting breathlessness and a demand for oxygen cylinders and beds that has led to health systems being overwhelmed.
Of 438 sequences of the VOCs analysed in Delhi, 415 exhibited the U.K. strain and 23 the South Africa strain. Delhi was among the States, along with Punjab, Chhattisgarh and Gujarat where instances of the U.K. strain in the wider community far outnumbered those detected among international travellers and their contacts.
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For instance, in Delhi, there were 324 instances of the U.K. strain in the “community” as opposed to 91 among travellers and their contacts (T&C). In Gujarat, it was 18 in T&C and 42 in the community and in Chhattisgarh there was only 1 case in the T&C as opposed to 14 in the community. Such numbers weren’t yet present for the Brazilian and South African strains. Several of these states are showing unprecedented spikes.
The comparative data was presented by Dr. Singh.
So far about 15,000 genomes had been sequenced, which is about 1% of India's coronavirus caseload.
Dr. Anurag Agrawal, Director, CSIR-Institute of Genomics and Integrative Biology (IGIB), said the concern with the Indian variants was that they possessed two mutations — E484K and L245R — that together would increase the likelihood of a wider range of antibodies being unable to counter the virus.
“However immunity also includes a cellular level response that can generate cross reactivity and so we can still expect, a good antibody response which is why all vaccines, despite the variant, will be fairly protective (against disease),” he said.
Dr. Priya Abraham, Director, ICMR-National Institute of Virology said the virus would continue to mutate and the best defence would be to continue following ‘COVID appropriate behaviour' and vaccinate at the earliest. She said that 90% of the RT-PCR tests being deployed were accurate. However, there were challenges in testing with several trained staff too testing positive and affecting the quality of testing and analysis, she added.
Virologist Shahid Jameel, and head of the advisory group to INSACOG, who was moderating the webinar, said there was “preliminary” information that both Covaxin and Covishield appeared to be effective against the Indian variant. He was referring to a report by the CSIR-Centre for Cellular and Molecular Biology, Hyderabad.
“Science is a process that calls for evidence based policy making and not policy based evidence making. Three 'T's are needed: Truth, Transparency and Trust. Truth leads to transparency leads to trust,” he said.
