A health worker administers a nasal swab test at a Testaro Covid-19 mobile testing site outside Richmond Corner shopping center in the Milnerton district of Cape Town, South Africa, on Thursday, Dec. 2, 2021. South Africa announced the discovery of a new variant, later christened omicron, on Nov. 25 as cases began to spike and the strain spread across the globe. Photographer: Dwayne Senior/Bloomberg “If we are lucky, omicron is less pathogenic, and this immunity will help push delta out,” said Sigal, who has previously found a two-dose course of Pfizer Inc. and BioNTech SE’s Covid-19 shot as well as a previous infection may give stronger protection against omicron.
The study is based on 15 participants, of which two were excluded as they didn’t detectably neutralise omicron, and the data are being submitted to MedRxiv, a preprint medical publication. It has not been peer reviewed.
Since the participants had probably suffered previous Covid-19 infections and were largely vaccinated, it’s not clear if the results show the impact on delta by omicron-elicited antibodies or the activation of antibodies, the authors said.
Still, the latest findings suggest the likelihood of someone infected with omicron being reinfected by delta is limited, reducing the presence of the latter strain. Omicron is the dominant variant in South Africa’s fourth wave of infections, delivering record case numbers, and is fast becoming the dominant strain globally.
Delta ripped through the country in July and August, leading to record hospitalization figures. Omicron hasn’t yet had such an impact on health services. BM