Sub-lineages of Delta variant — AY.1, which is commonly known as the Delta Plus, and AY.2 — are unlikely to be more transmissible than the parent, said INSACOG, a consortium of government panel involved in genome sequencing of coronavirus.
These two sub-lineages are also below 1 per cent in the genome samples sequenced in the country in June, it said in a recent bulletin.
INSACOG also said AY.3 has been identified as a new Delta sub-lineage and it is defined by ORF1a: I3731V common AY.1 mutations except for S: K417.
This is primarily seen in the US with single reclassified cases in the UK and India. However, there is “no known significant property” of this mutation. But since it is a Delta variant of concern (VOC) sub-lineage, INSACOG will continue to monitor it, the bulletin stated.
“Delta sub-lineages AY.1 and AY.2 are declining globally with near-zero cases in the last week of June in either the UK or US, where they were most frequently seen. They also continue to be below 1 per cent in available sequences from June in India.
