Antibodies generated by Omicron, a Covid-19 strain, are not only effective against it but also against other variants of concern (VOCs), including Delta, according to the latest study conducted by the Indian Council of Medical Research (ICMR).
“The individuals infected with Omicron have significant immune responses which could neutralise not only the Omicron but also the other VOCs, including the most prevalent Delta variant,” it said.
“This suggests that the immune response induced by the Omicron could effectively neutralise the Delta variant making the re-infection with Delta less likely, thereby displacing the Delta as dominant strain. This emphasises the need for the Omicron-specific vaccine strategy,” it further said.
In this study, the ICMR has analysed the IgG and neutralising antibodies (NAbs) against B.1, Alpha, Beta, Delta and Omicron variants with the sera of individuals infected with the Omicron variant (B.1.1529 and BA.1) .
ICMR has said within a short span of time, the variant has shown high transmissibility and capability of evading the immune response generated against natural infection and vaccination. The immune escape potential of Omicron is a serious concern and further needs to be explored.
The study, where antibodies response was assessed in those who are infected by Omicron, is pre-print not peer-reviewed.
It also stated, “In the present study, we have assessed the IgG and neutralising antibody (NAb) response in breakthrough individuals vaccinated with two doses ChAdOx1 nCoV-19 vaccine (n=25), breakthrough individuals vaccinated with two doses of BNT162b2 mRNA vaccine (n=8) and unvaccinated individuals (n=6). All these individuals were infected with the Omicron variant.”
Also, 28 of these 39 were mainly foreign returnees from the UAE, South/West/East Africa, Middle East, the US and the UK, and 11 people were their high-risk contacts. All these individuals were infected with the Omicron variant.