Omicron does not completely escape immunity induced by Pfizer vaccine

Data shows considerable immunity is retained in people who were both vaccinated and previously infected.



According to a recent study headed by the Africa Health Research Institute, the SARS-CoV-2 Omicron variant escapes antibody immunity induced by the Pfizer-BioNTech COVID-19 vaccine. Results from the study also showed that considerable immunity is retained in people who were both vaccinated and previously infected. “The clinical implications of these important laboratory data need to be determined. It is likely that lesser vaccine-induced protection against infection and disease would be the result. Importantly, most vaccinologists agree that the current vaccines will still protect against severe disease and death in the face of Omicron infection. It is therefore critical that everyone should be vaccinated,” said Africa Health Research Institute executive director Professor Willem Hanekom in an accompanying statement this week.


The institute tested samples from 12 participants with 6 participants having no previous record of SARS-CoV-2 infection nor detectable nucleocapsid antibodies indicative of previous infection. The remaining 6 participants had a record of previous infection in the first wave of the virus. The results presented in an online manuscript, indicated that, "Previous infection, followed by vaccination or booster is likely to increase the neutralization level and likely confer protection from severe disease in omicron infection. The Omicron variant, which was classified as a variant of concern by the World Health Organization late last month was first announced in Southern Africa. Since then, more than two dozen countries from Japan to the United States have reported active cases.