Of the 30,230 samples of variants of concern and variants of interest sequenced so far in India, a significant 20,324 were of Delta variants causing breakthrough infections, INSACOG, a genome sequencing Government consortium of laboratories has said.
The continuing Covid-19 outbreaks across India are attributable to, besides the Delta variant, a susceptible population and reduced vaccine effectiveness in blocking transmission, the INSACOG added.
However, vaccination continues to be very effective in reducing severe disease and death, and public health measures such as mask and hygiene to reduce transmission and inoculation remain critical, the INSACOG stressed in its latest bulletin dated August 16.
“As of now, sequencing of vaccination breakthroughs in India is also showing a very high proportion of Delta variants. Investigations for any new variants are ongoing,” the INSACOG said.
Of the 30,230 samples of variants of concern and variants of interest sequenced by the INSACOG, 20,324 were of Delta, it said.
Citing an example of the UK where with a population of about 6.7 crore, about 18 lakh cases and 1.2 lakh vaccination breakthroughs with Delta since April 2021 have been reported, the INSACOG said, thus, vaccination breakthroughs are common during Delta outbreaks and are expected in India as well.
The Delta variant is currently driving the pandemic across several countries with China and Korea seeing new highs. Korea has reported that the new surge is due to Delta plus K417N mutation.
The Delta variant resulted in a deadly second wave in the country between March and May that wreaked havoc on the health infrastructure, overwhelming hospitals. It infected lakhs and killed thousands.
In India, new cases of AY.1, AY.2, AY.3 (Delta Plus) are being seen in July samples from Maharashtra at a frequency of about 1 per cent. However, at this time none of these sub-lineages has been found to have a growth advantage over the Delta parent lineage, it noted.
According to INSACOG (the Indian SARS-CoV2 Genomics Consortium), 61 samples of Delta Plus variants have been detected in the country so far.
"Delta variant is the major VOC in India at this time. Continuing outbreaks across India are attributable to Delta, a susceptible population, reduced vaccine effectiveness in blocking transmission, and opportunities for transmission," the INSACOG said.
The active cases have declined to 3,63,605, the lowest in 150 days, and comprise 1.12 per cent of the total infections, the lowest since March 2020, the Health Ministry said on Friday. Over 57 crore jabs have been administered in the country so far, the Health Ministry added.
The R Value, or the Reproduction rate in the country has also dipped to 0.89 from August 14-16. But the country continues to post over 25,000 cases everyday.