'Delta variant accounts for 80% of new Covid cases'

New Delhi: The Delta variant was primarily responsible for the second wave of COVID-19 in the country, accounting for over 80 per cent of new cases, Dr N K Arora, co-chair of Indian SARS-CoV-2 Genomics Consortium said, underlining that the cases may go up if a new, more infectious variant comes.

The variant is also around 40-60 percent more transmissible than its predecessor, Alpha variant, and has already spread to more than 80 countries, including the UK, the US and Singapore.

India saw a single-day rise of 38,164 new infections, while the death toll climbed to 4,14,108 with 499 fresh fatalities, the lowest in over three months, according to the Union Health ministry data updated on Monday.

The COVID-19 case tally has climbed to 3,11,44,229 though the number of people who have recuperated from the disease also surged to 3,03,08,456 and the case fatality rate stands at 1.33 per cent, the data stated. The active cases have declined to 4,21,665 and comprise 1.35 per cent of the total infections, while the national COVID-19 recovery rate stands at 97.32 per cent, the data updated at 8 am showed.

The Delta Plus variant AY.1 and AY.2 has so far been detected in 55-60 cases across 11 states, including Maharashtra, Tamil Nadu, and Madhya Pradesh and is still being studied for its transmissibility, virulence, and vaccine escape characteristics, Dr Arora said, according to a ministry statement.

The Delta variant has mutations in its spike protein, which helps it bind to the ACE2 receptors present on the surface of the cells more firmly, making it more transmissible and capable of evading the body's immunity, Dr Arora said.

"The B.1.617.2, a variant of COVID-19 known as the Delta variant, was first identified in October 2020 in India, and was primarily responsible for the second wave in the country, today accounting for over 80 percent of new COVID-19 cases," he said.

It emerged in Maharashtra and travelled northwards along the western states of the country before entering the central and the eastern states.

On whether it causes more severe disease as compared to other variants, Dr Arora said there are studies that show that there are some mutations in this variant that promote syncytium formation.

"Besides, on invading a human cell, it replicates faster. It leads to a strong inflammatory response in organs like the lungs. However, it is difficult to say that disease due to the Delta variant is more severe. The age profile and the deaths during the second wave in India were quite similar to that seen during the first wave," he stated.