According to top officials who said on Tuesday that E484K and N440K changes were seen in samples taken from some people in Maharashtra and Kerala, some mutations of the Sars-Cov-2 that have been troubling scientists globally have emerged in India.
The statistics apply to changes in the proteins of the pathogen, which can tweak its structure. In order to decrease the effectiveness of vaccines and to make immunity from a previous infection ineffective, at least one of these improvements has been described as E484K.
But officials added that whether these are behind the revival in the two states has yet to be known. 'There is no direct connection between the recent increase in cases of Covid-19 in Maharashtra and some other states where the N440K and E484K mutations [have occurred],' said Dr. Balram Bhargava, Director General, Indian Council of Medical Research (ICMR), at the weekly Covid-19 update media briefing.
...These two strains of viruses were also found in other countries and are not unique to India. In addition, in some states in India, they have been identified earlier,' said Bhargava, without providing more information about these strains.
Mutations are not rare and until December, when new variants with a large number of mutations began to emerge, the Sars-Cov-2 collected about two per month. There are nine mutations in the South African version (known as B.1.351) that modify its structure, including E484K that occurs in the spike protein, the virus component that plays a role in host cell entry.
The two mutations were picked up during routine genomic surveillance of cases, according to Niti Aayog member (health), Dr. VK Paul. The genomes of a proportion of positive cases have been analyzed by the Indian Sars-Cov-2 Genomic Consortium (INSACOG). In addition to these, the existence of the UK-linked B.1.1.7 and the Brazil-linked P.1 variant has been confirmed by the consortium.
All these cases were detected in the case of foreign travelers. But those that have appeared in India have also been identified earlier, the officials said. In December last year, INSACOG was formed as a network of 10 government laboratories to perform 5% Covid-19 sample genome sequencing.
The effort has gathered momentum, and among Covid-19 positive samples, the network of labs has sequenced 3,500 viruses so far.
Along with six South African variants and one Brazilian variant, nearly 200 (187) UK variants have been picked up, Paul said.
"You are not only searching for these variants while you are doing sequencing but also looking for any odd shift or alteration in the character of the virus. And we have to say the effort took place well before the UK version entered the nation as an indigenous effort. As it is in their existence, these mutations continue to occur in viruses,” he added.
Paul also added that the action of mutants in the country was continuously watched by researchers, not just the three variants that are now global variants of concerns.
Experts believe that unless it is known that the mutation is either more transmissible or has the increased potential to kill, there is no reason for concern.
"Respiratory virus mutations occur all the time, but what is important is to monitor mutated virus behavior to see what it clinically means," said Dr. Shobha Broor, former head of the Department of Microbiology, All India Institute of Medical Sciences, Delhi.