BENGALURU: The state Covid-19 Genomic Surveillance Committee has found that with two sub-lineages of the Delta variant, there is little variation in the spike protein. The two sub-lineages are AY.4 and AY.12.
In AY.4, the G142D mutation is present in only 26% of the sequences and the same mutation is found in only 1.3% of the AY.12 sequences, shared Dr Vishal Rao, member of the Genomic Surveillence Committee and chief of Head and Neck Surgical Oncology and Robotic Surgery at HCG Cancer Centre.
“This does not mean we let our guard down, as in Israel, AY.12 is causing a surge in cases. We need to keep a close watch hereon for vaccine escape mutations and breakthrough infections, as they are related. The next six months will be crucial and we need to increase vaccine coverage and follow Covid appropriate behaviour,” said Dr Rao, adding that the Delta variant has properties of vaccine escape, but the vaccine has largely been effective against it.
A significant population of India, including health workers, took the vaccine eight months ago and immunity will phase out. If a new strain appears which is more transmissible, it may have higher infection rate. Hence, we need to remain vigilant, said Dr Taslimarif Saiyed, CEO and director of C-CAMP, as well as a member of the surveillance committee.
“We need to be cautious until the reproductive rate of the strain goes down. We cannot predict which mutation will infect more people. Genomic sequencing will only help us find the trend of the mutation, to manage it but not to predict it,” Dr Saiyed explained. As of October 11, there are 1,653 samples of Delta variant detected, 202 of AY.4 and 14 of AY.12.