Delta variant 40-60% more transmissible than Alpha: Top official

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.

Published: 19th July 2021 01:59 PM  |   Last Updated: 19th July 2021 06:55 PM   |  A+A-

Covid test samples collected by a health worker. (File Photo | PTI)

For representational purpose. (File Photo | PTI)

By Express News Service

NEW DELHI: A top government official has now said that the Delta variant of coronavirus is 40-60% more transmissible than the Alpha variant.

NK Arora, co-chair of INSACOG, a government initiative for Covid genomic surveillance in India, however, added that it has not yet been conclusively established whether this variant, which first emerged in Maharashtra and has now reached over 80 countries, can cause more severe disease.

B.1.617.2, a variant of SARSCoV2 was first identified in October 2020 in India and was primarily responsible for the second wave in the country. It now accounts for over 80%t of new Covid cases.

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This 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.

“It is around 40-60% more transmissible than its predecessor (Alpha variant) and has already spread to more than 80 countries, including the UK, the USA, Singapore, and so on,” said Arora in a statement on Monday. 

There have been studies that show on invading a human cell, this variant replicates faster which leads to a strong inflammatory response in organs like the lungs.

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“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,” Arora said.

On Delta Plus variant -- AY.1 and AY.2 -- whose 55-60 cases across 11 states, including Maharashtra, Tamil Nadu, and Madhya Pradesh have been detected so far, Arora said that the variant is still being studied for its transmissibility, virulence, and vaccine escape characteristics.

ALSO READ: Delta 8 times less sensitive to vaccine antibodies

On the continued rise in cases in some states in India, including northeastern states and Kerala, the official said that most of these cases could be due to the Delta variant.

On future Covid waves in the country, Arora said that the cases may go up if a new, more infectious variant comes.

“Any future waves will be controlled and delayed if more and more people get vaccinated and most importantly, people follow Covid-appropriate behaviour effectively, especially till a substantial part of our population gets vaccinated,” he said.

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