Jabs only answer as Omicron, Delta variants co-exist: Experts

Senior virologist and Former Director of ICMR’s Centre of Advanced Research in Virology Dr T Jacob John emphasized vaccinating children quickly to minimise the virus transmission and risk of emergence of new variants by mutations. He said children’s vaccination with vaccines that are safe and effective should be administered. “The risk of disease and death is low but not zero even in normal children. Post-infection they are at risk for the multi-system inflammatory syndrome (MIS) and diabetes —Children with chronic diseases are at high risk of COVID itself — all these are prevented by vaccination. If children are left unvaccinated, they will act as a virus reservoir, and we know Omicron infects children quite readily,” he said.

While Delta has two mutations on the receptor-binding domain of the spike protein, Omicron has 15. This has resulted in evasion from antibody binding, necessary for protection. Neutralising antibodies against the spike protein of the original virus, induced by all available vaccines (mRNA or adenovirus-vectored) are relatively ineffective against Omicron. However, recent experience shows that very high levels of antibodies that result from booster doses offer protection, especially from severe diseases needing hospitalisation. Dr V Ravi, former professor of neurovirology at Nimhans said self-test kits give reliable results in symptomatic patients; however asymptomatic patients must undertake RT-PCR tests for results especially when there is a huge surge in cases. He remarked that current data shows that Omicron is seen more in double vaccinated people thus it is in our best interest that we don’t let our guard down.

On mixing of two different vaccines, he said, “There is no clear-cut data on mixing of vaccines in India. Thus, our current policy on using the same dose vaccine as a booster is in our best interest.” Dr V Ramasubramanian, Consultant Infectious Diseases - Tropical Medicine, Apollo Hospitals, said either their fever settles within 24 hours or 4 to 5 days. “These all cases are symptomatic, and they are responding to the treatment. Besides fever, they are reporting severe throat pain,” he said.