Study finds low Omicron antibody response with COVID-19 vaccinesOnly 20% and 24% of Pfizer/BioNTech COVID-19 vaccine recipients in a Chinese study had detectable neutralizing antibodies against two isolates of the highly transmissible Omicron (B.1.1.529) variant, while recipients of the Coronavac vaccine had no antibodies against either isolate.The study, published today in Clinical Infectious Diseases after appearing on a preprint site 2 days ago, was led by University of Hong Kong researchers, who isolated Omicron strains HKU691 and HKU344-R346K from patients.Only 20% and 24% of Pfizer vaccinees had antibodies against HKU691 and HKU344-R346K, respectively.