Delta variant of Coronavirus mutates to 'Delta Plus', why you don’t need to panic
New Delhi, June 15: Delta varaiant was the fourth addition to a list that also includes variants first identified in the UK, South Africa, and Brazil, blamed for the disatraus second wave of coronavirus infections in India.
The super infectious, Delta variant (B.1.617.2) of SARS-CoV-2 has mutated further to form the 'Delta plus' or 'AY.1' variant, triggering fears that these viruses will be able to evade the immune response.
However, health experts have said that there is no immediate cause for concern in India as its incidence in the country is still low. The scientists have suggested that two doses of vaccines, putting up masks and implementing Covid appropriate norms would help fight the virus.
Studies suggests that the Delta plus variant shows signs of resistance against the monoclonal antibody cocktail treatment, which was recently authorised by the Central Drugs Standard Control Organisation (CDSCO) in Inida.
What is Delta Plus or AY.1 COVID-19 varaiant
The B.1.617.2.1 Covid-variant also known as AY.1 characterised by the acquisition of K417N mutation and the mutation is in the spike protein of SARS-COV-2, which helps the virus enter and infect the human cells.
The Delta plus variant was present in six genomes from India as of June 7. So far, 63 genomes of Delta (B.1.617.2) with the new K417N mutation have been identified so far on the global science initiative GISAID.
Delta plus variant mostly found in Europe, not India
In fact, the Delta Plus variants are mostly found in Europe, Asia and America other than India. The earliest sequence of this genome was found in Europe in late March this year.
Delta plus found evading monoclonal antibody treatment
An important point to consider regarding K417N is the "evidence suggesting resistance to monoclonal antibodies Casirivimab and Imdevimab". Monoclonal antibodies, which were considered to be a viable treatment for Covid-19, has been touted to be as game changer' in the fight against the pandemic.
Monoclonal antibody (mAb or moAb) is an antibody made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell.
Researchers have revealed that the use of mAbs is the foremost innovative approach that could prevent as well as treat infected patients. Several researchers are focusing on developing new cures based on specific mAbs to inhibit and/or neutralize SARS-CoV-2 in COVID-19 patients.
Casirivimab and Imdevimab are monoclonal antibodies that are specifically directed against the spike protein of SARS-CoV-2, and designed to block the virus'' attachment and entry into human cells.
Transmissibility of new variant a crucial factor
Allaying fears, immunologist Vineeta Bal noted that while there may be some setback in the use of commercial antibody cocktail due to the new variant, resistance to the therapy is not an indication of higher virulence or severity of a disease.
"How transmissible this new variant is will be a crucial factor to determine its rapid spread or otherwise," Bal, guest faculty at the Indian Institute of Science Education and Research, Pune, told PTI.
She also noted that the quality and quantity of neutralising antibodies, responsible for defending cells from pathogens, generated in the individual infected with the new variant is unlikely to be affected because of the mutation.
"Thus in individuals catching infection with the new variant, it may not be a matter worth worrying," she added.
Pulmonologist and medical researcher Anurag Agrawal concurred.
"There is no cause of concern due to the new variant in India as of now," Agrawal, the director of CSIR-IGIB, told PTI.
Plasma from vaccinated people will have to be tested
The scientist said the blood plasma from many fully vaccinated individuals will have to be tested against this variant to determine whether it shows any significant immune escape. As the Delta variant continues to evolve and acquire new mutations, there is a lot of interest in understanding its evolution.
He said SARS-CoV-2 has a nearly constant rate of acquiring genetic variants, and each variant has acquired additional variants in a stepwise fashion.
"Understanding this continued evolution is of great importance in mapping the evolutionary landscape of emerging variants. Largely the virus has tried to optimise for transmission and immune escape by step-wise acquisition of new mutations," he added.