Omicron Induced Immunity To Neutralise Other COVID-19 Variants Says ICMR

Omicron has a significant immune response that has the ability to neutralise other variants of concern which includes the Delta variant as well.

A study was conducted by the Indian Council of Medical Research and the National Institute of Virology of Pune which proved that the immune response induced by Omicron could neutralise the Delta variant, making the re-infection less likely.

Hence, the study went ahead and emphasised the need for an Omicron specific vaccine strategy as it is capable of displacing the Delta as the dominant strain.

“This suggests that the immune response induced by Omicron could effectively neutralise the Delta variant, making reinfection with Delta less likely. This emphasises the need for Omicron-specific vaccine strategy,” said the researchers.

Omicron Antibodies Act Against Other Variants Too:

The study conducted by the ICMR was conducted on thirty nine individuals, twenty five of whom had already taken both doses of the AstraZenenca vaccine against COVID-19. Eight people had taken the double dose of Pfizer and six were non-vaccinated.

All thirty nine adult individuals were infected with the Omicron variant. Most of these individuals were foreign returnees from countries such as UAE, South/West/East Africa, Middle East, US and the UK. Twenty eight were foreign returnees while eleven were their high-risk contacts.

The study mainly focused on assessing the IgG antibody and Neutralising Antibody (Nab) response in the people with breakthrough and natural COVID-19 infections.

"The GMTs of neutralising antibodies of ChAdOx1 nCoV-19 breakthrough individuals showed significant fold-reductions compared to B.1 against Alpha (3.23), Beta (2.38), Delta (3.23) and Omicron (4.31) variants respectively. Similarly, BNT162b2 mRNA breakthrough individuals demonstrated significant fold-reduction in GMTs of 1.52 and 7.41 for Delta and Omicron respectively," it said.

"Our study demonstrated substantial immune response in the individuals infected with Omicron. The neutralizing antibodies could effectively neutralize the Omicron and other variants of concern (VOCs), including the most prevalent Delta variant," said the study.

The study has been conducted by ICMR scientists, including Pragya D Yadav, Gajanan N Sapkal, Rima R Sahay and Priya Abraham. It is yet to be peer-reviews and has been released on bioRxiv pre-print server on January 26,2022.

Suggested Reading: Moderna Booster Trial Targeting Omicron Variant Begins