Covid vaccine efficacy limited against Omicron, says study
India TodayPeople who are double-vaccinated and those who have recovered from infection by previous strains of the SARS-CoV-2 virus have virtually no antibody protection against the Omicron variant, according to a study. Read: Very small blood clot risk after first AstraZeneca Covid shot, say UK studies They adapted for Omicron a test developed for the previous variants, which investigates whether the virus can bind to the receptor on human cells via its receptor-binding domain. The RBD differed only slightly in all previously known SARS-CoV-2 variants so that infections with these and the currently available vaccines provided protection against the previous variants, the researchers said. Consequently, infections with the previous variants and currently available vaccines provide little or no protection against Omicron, they said. The researchers noted that the best protection would be to develop a broadly effective combination vaccine that protects against both the previous variants and Omicron.