The AstraZeneca vaccine (Vaxzevria) confers “immunity” to Covid 19 “even after one year from a single dose”. This was established by a study, which will be published in the ‘Lancet’, of the University of Oxford. The pre-print results “showed that antibody levels remain elevated for at least a year after a single dose,” AstraZeneca points out in a note. Vaxzevria vaccine “resulted in an up to 18-fold increase in antibody response when the interval between first and second doses was up to 45 weeks, a result measured 28 days after booster.”
“With a 45-week dosing interval between the first and second dose, antibody titers were four times higher than in a 12-week interval – the study highlights – demonstrating that a longer period between first dose and booster it is not harmful but it can give stronger immunity “.
A third dose of Vaxzevria “administered at least 6 months after the second, increased antibody levels sixfold and maintained T cell response. A third dose also resulted in increased neutralizing activity against Alpha, Beta and Delta variants”, still established the studio. According to the pre-print results, “both the second and third doses caused fewer adverse reactions than the first”.
The study reveals “reassuring news for countries with lower vaccine supplies, which may be concerned about delays in administering second doses – warns Andrew J. Pollard, lead researcher of the Oxford Vaccine Group – There is an excellent answer at a second dose, even after 10 months of delay from the first “.
“Demonstrating that our vaccine generates a robust and long-lasting immune response is important for building confidence in long-term protection,” said Mene Pangalos, executive vice president of AstraZeneca’s biopharmaceutical research and development.