Third jab ‘significantly’ boosts Omicron antibodies: AstraZeneca

British pharmaceutical giant AstraZeneca
said Thursday that a third, or “booster”, dose of its Covid-19 vaccine
Vaxzevria “significantly” lifted antibody levels against the Omicron strain
in a laboratory study.

“Vaxzevria significantly boosted levels of antibodies against the Omicron
SARS-CoV-2 variant (B.1.1.529) following a third dose booster,” the company
said in a statement citing the study.

“The third dose booster vaccination neutralised the Omicron variant to
levels that were broadly similar to those observed… after the second dose
against the Delta variant,” it said.

Levels of neutralising antibodies were also higher with the booster jab
than with individuals who had previously been infected and recovered
naturally from Covid-19.

The study was conducted by investigators from the University of Oxford,
which is the academic institution which helped AstraZeneca develop the
vaccine last year.

The study analysed blood samples taken from individuals infected with
Covid-19; those vaccinated with two doses plus a booster; and those who had
reported previous Covid infection.

“It is very encouraging to see that current vaccines have the potential to
protect against Omicron following a third dose booster,” said University of
Oxford professor John Bell, one of the study investigators.

“These results support the use of third dose boosters as part of national
vaccine strategies, especially to limit the spread of variants of concern,
including Omicron.”

On Wednesday, the World Health Organization had warned that rich countries
cannot use boosters to escape the Covid crisis, as they divert valuable jabs
away from poorer nations — and encourage the virus to spread and mutate.

The threat of the highly transmissible Omicron variant is looming large
over the end-of-year holidays, pushing many governments to roll out new
restrictions and urge citizens to get vaccinated.

The latest data suggest Omicron does not cause more severe illness than
previous variants, including Delta, but as soaring infection numbers threaten
to overwhelm health systems, scientists warn it could still cause more
deaths.

AFP