A new study has found that two doses of vaccine brands Sinovac and Pfizer/BioNTech are not enough to defend against the new Omicron variant, which was first detected in South Africa in November.
The study about the risks of the Omicron variant and the need for a universal third dose by microbiologists at the University of Hong Kong (HKU) showed that recipients of Coronavac's Sinovac two-dose series did not develop enough antibodies to defend against Omicron. Meanwhile, those who completed the two-dose BionNTech vaccine had a slightly higher number of individuals who developed antibodies.
The study gathered two groups of 25 individuals each—one that has received two doses of the Pfizer/BioNTech vaccine and another one that has completed their Sinovac vaccination—and tested their serum antibodies to neutralize Omicron.
Among those who received Coronavac vaccine, none of the serum of its recipients contained sufficient antibody “to neutralize the Omicron variant,” the researchers noted. On the other hand, only five out of the BioNTech group had a "neutralizing ability" against the Omicron variant virus.
“Compared to the original SARS-CoV-2 strain," the study noted that the ability of the Sinovac and Pfizer/BioNTech vaccines to neutralize the Omicron variant fell by 34-60 fold.
The researchers advised the public "to get a third dose of the vaccine as soon as possible while awaiting for the next generation of more matched vaccine."
Pfizer/BioNTech previously said that while two jabs of their vaccine won’t be sufficient to fight the Omicron strain, they emphasized that it’s “still effective” after a third one. Additionally, a separate research in South Africa found that two shots of it offer 70% protection against severe disease from Omicron.
“The double dose of Pfizer/BioNTech vaccine shows 70% effectiveness in reducing risk of hospitalization,” according to Ryan Noach of South Africa’s leading private health insurance company that also co-headed the study.
A New York magazine story also noted that current laboratory testing still indicates that those who have been fully jabbed can still be shielded against severe outcomes with the Omicron variant, but such “is notably lower than against Delta.”
In November, the World Health Organization declared Omicron as a “variant of concern,” putting it under the list of troubling COVID-19 variants including Delta as well as weaker ones like Alpha, Beta, and Gamma.
The WHO on Tuesday, Dec. 14 also warned the public that the variant was spreading at an “unprecedented rate,” urging countries to take action and step up their health systems.