Delta continues to be the dominant Covid variant in circulation in Maharashtra and India, but the presence of one of its derivatives or sub-lineages, named AY.4, is growing. Scientists said it’s too early in the Covid cycle to ascertain if AY.4 is a matter of concern.

from Times of India https://timesofindia.indiatimes.com/city/mumbai/delta-derivative-ay-4-soars-in-maharashtra-state-india-samples-but-not-of-concern-yet/articleshow/86380604.cms