BENGALURU: Though Karnataka does not figure among the states listed by the Union Health Ministry where the Delta plus variant has been detected, two cases have been found among less than hundred samples sequenced for this variant. While one was sequenced at the Department of Virology’s lab at NIMHANS, the other was from the National Centre for Biological Sciences (NCBS). Experts are now calling for urgency to not just step up genome sequencing, but also rework vaccines to ensure their efficacy against the SARS-CoV-2 variants.
“One sample from Mysuru had the Delta plus variant and another was from a person hailing from Tamil Nadu whose sample was sequenced at NCBS in Bengaluru,” said a senior virologist from the Genomic Surveillance Committee, who did not want to be identified.
Though Dr V Ravi, nodal officer for INSACOG genomic confirmation of SARS-COV-2, and chairman of Covid-19 Genomic Surveillance Committee, has said that the Delta plus variant was not yet one “of concern” and there is no proof of it being highly transmissible, experts say this is worrisome and needs immediate attention. This variant has so far been found in 22 samples in Maharashtra, Kerala and Madhya Pradesh.
Dr Vishal Rao, Dean, Centre for Academic Research at HCG Cancer Centre, Member of Karnataka COVID Task Force Genomic Surveillance Committee, said detailed studies across countries have proved that with an increase in number of cases, the chances of mutations escaping vaccines are higher. “Right now, the most important application is that of getting advance notice of shifts in disease dynamics using genomic surveillance. A (pre-print) paper from ICMR-NIV shows that B.1.1.28.2 (P.2) variant was isolated from nasal/throat swabs of international travellers returning to India from the UK and Brazil,” he said.
Researchers believe that findings of increased disease severity and neutralisation reduction in animal models can be a matter for concern, and stressed the need for further screening of vaccines for their neutralisation effect and efficacy, and ramp up genomic surveillance efforts to monitor this new variant and other emerging variants.
“It is important to rework vaccines and update them along with the development of new vaccines due to the emergence of newer variants of concern. It is most important to conduct concurrent genomic sequencing, and epidemiological investigation as it can steer the Covid-19 response,” said Dr Giridhara Babu, epidemiologist and member of the Covid-19 Technical Advisory Committee. “In the event of newer variants of concern emerging, they will have to be isolated and used to update the existing vaccines.”
On Tuesday Maria van Kerkhove, the World Health Organisation’s (WHO) technical lead for Covid, in a press conference, also warned against giving the virus any chance to mutate further. She said that although the current vaccines are able to offer great protection against severe illnesses, “it is a worrying trend which could leave vaccines completely ineffective against potential highly mutated variants.”