RIO DE JANEIRO, BRAZIL - A third dose of AstraZeneca's Covid-19 vaccine from Oxford University produces a strong immune response, researchers said Monday, adding that there is no evidence yet that such a booster dose is required, particularly given vaccine shortages in some countries.
The Oxford University study showed that a third dose of the vaccine boosts antibody and T-cell immune responses, while the second dose administration may be delayed until up to 45 weeks after the first and still lead to an enhanced immune response.
The UK government says it is considering plans for a booster dose . . .