Bloomberg — A two-shot course of Pfizer Inc.’s vaccine has just 22.5% efficacy against symptomatic infection with the omicron variant, but can thwart severe disease, according to laboratory experiments in South Africa.
Additional data was released by researchers at Africa Health Research Institute, Durban on an earlier study.
Twelve participants were included in the study. The researchers examined blood plasma samples. The scientists found that people who were given two doses Pfizer BioNTechSE shots had a 41-fold lower level of neutralizing antibody levels than those who were exposed to the same strain in China nearly two years before.
This is “essentially compromising the ability of the vaccine to protect against infection,” said the team of scientists led by laboratory head Alex Sigal in a preprint released on Friday.
According to them, there continues to be enough protection against severe illness.
The team this week was the first to show that the variant, found by scientists in South Africa and Botswana and announced on Nov. 25, could largely, but not totally, escape the antibodies produced by Pfizer’s vaccine. They did say that a booster shot might increase immunity. That’s been backed up by studies carried out by Pfizer itself.
