An Oxford University study published on Monday found that two-dose COVID-19 vaccines generate a lower antibody response against the omicron strain, suggesting that the variant could lead to more infections among the fully vaccinated and previously infected.
The research, which has not yet been peer-reviewed, documented a "substantial fall" in the number of neutralizing antibodies among participants who received two doses of the AstraZeneca or Pfizer-BioNTech vaccines.
The results do not provide evidence that the omicron strain causes more severe disease, hospitalizations or deaths in vaccinated individuals. But it does indicate that the variant could lead to more cases among those vaccinated with two doses.
The study adds to a growing body of evidence supporting the push for booster doses that have been shown in other research to boost antibody levels against the omicron strain.