Booster shots of COVID-19 vaccines would help protect people against Omicron, Dr. Chandima Jeewandara of the Allergy, Immunology and Cell Biology Unit, Department of Immunology Molecular and Molecular Medicine of the University of Sri Jayewardenepura said yesterday.
Dr. Jeewandara said the first Omicron lab data had been released by a group of South African scientists within two weeks since reports on the variant came to light. The South African scientists have looked at how Omicron enters human cells and how antibodies respond to Omicron, compared to the original SARS-CoV-2 virus. The scientists have found that the new variant used the same receptor to enter human cells.
Among people vaccinated with the two-dose Pfizer series, neutralising antibodies had a 40 fold reduction with Omicron compared to the original virus.
“This is far higher than we’ve seen with any previous variants of concern (Delta had a 5 fold decrease; Beta had an eight-fold decrease). Previous infection, followed by vaccination or booster is likely to increase the neutralisation level and will likely confer protection from severe disease in the event of Omicron infection.”
Dr. Jeewandara predicted that the world would see an increase in breakthrough cases, especially among those with only two doses of the COVID-19 vaccine.
“In addition, and importantly, neutralizing antibodies are not our only defence. We have other antibodies, B-cell factories, and T-cells. There was hope that Omicron might not spread fast unlike in Europe and that we wouldn’t necessarily see the same rate of spread as in South Africa because high rates of Delta and vaccination would be in Omicron’s way,” he said.
However, data from the UK suggests that high levels of Delta and/or immunity were not stopping Omicron in the UK. “Anticipate this in Sri Lanka too. But we need more data for this conclusion,” he said. (RK)