Delta Plus variant, a mutated version of the more aggressive B.1.617.2 strain that drove the second wave of infections in India, is undergoing additional mutation called K417N which could become a "variant of concern" if unchecked, said AIIMS Chief Dr Randeep Guleria, adding that India needs to learn from the UK where the said variant is causing a surge in cases.
Dr Guleria said India could see a faster surge if aggressive Covid-appropriate behaviour is not followed. He also insisted on aggressive surveillance to guard against any spike in the Covid cases following unlocking in parts of the country.
"Delta plus is a variant which is of same lineage as Delta variant, with a slight change as there is one more mutation found, which could be a cause of concern because this mutation, the K417N, is something which may change the virus to some extent as far as its infectivity is concerned... What we need to do is observe. Currently, the WHO has said that this is a variant of interest but it could become a variant of concern because currently the number of cases is less. Will this Delta plus again become the dominant variant that is something that we need to observe over the next few weeks," said Dr Guleria in an interview to NDTV.
The B.1.617.2 variant is characterised as being highly infectious. The spike protein is what helps the virus enter and infect human cells, and the K417N mutation has been associated with immune escape, or evasion, that leaves it less susceptible, or more immune, to the vaccine or any form of drug therapy.
"We don't need to take this virus casually. We need to understand this virus is changing and changing to survive and infect more and more people, therefore we have to be aggressive and try and be ahead of the virus. The UK did a very good job by having an aggressive lockdown for many many months and when they started opening up, the new variant, the delta variant, caused the surge in number of cases. What it means is we are also in a similar vulnerable situation and if we are not careful right now then 3 or 4 months from now, we will again have a similar situation and that is why we need to be very aggressive; it is mutating, changing, new variants are coming up," said Dr Guleria.
There is need to ramp up genome sequencing, said Dr Guleria, to see if there are more of Delta or Delta plus cases and how the virus is behaving in terms of these two variants in the community.
"We need an aggressive genome sequencing to see how the virus is behaving. Does the vaccine efficacy come down, does the monoclonal antibody treatment work? To do all of that, we need to have a large or very good network of labs to study the data. I think that's where to move in the next few weeks. And that's the new frontier we need to develop if we want to succeed in our fight against Covid," added Dr Guleria.
The government, on its part, has said the Delta plus variant had been around since March this year. It is not, however, a variant of concern at this point, Dr VK Paul, Member (Health), NITI Aayog, said. "Its presence had been detected and submitted to global data system," he added.
Anurag Agrawal, Director of Delhi's CSIR-Institute of Genomics and Integrative Biology (IGIB), said there is no cause for concern as reports of the new variant are still low and there is no indication, as yet, about the severity of the disease.
Vinod Scaria, another CSIR-IGIB scientist, said the K417N variant was more frequent in Europe, America and other Asian countries.