Applying a third dose of Pfizer‘s covid-19 vaccine can “strongly” increase protection against the Delta variant of the coronavirus, improving the defense provided by standard doses. This is what suggests a new study released by the pharmaceutical this Wednesday (28).
The data, not yet reviewed by the scientific community, indicate that the extra dose of the immunizing agent can raise up to five times the levels of antibodies against the variant identified for the first time in India. This level would be reached in people aged between 18 and 55 years.
In the public aged 65 to 85 years, the protection achieved would be even greater with the booster dose. In this case, antibody levels against the Delta variant grow 11 times more than after the second application, according to the assay carried out by Pfizer.
Although the data suggest advantages in the extra application, it is not clear whether the increased antibody levels are related to better protection or if this boost is even necessary. In that regard, the US Centers for Disease Control and Prevention (CDC) claims that current formulas protect well against all common variants of Sars-CoV-2.
How long does the protection last?
Also recently released, another drugmaker’s article reveals that the protection provided by Pfizer’s coronavirus vaccine lasts for at least six months. During this period, the overall effectiveness was 91% and the effectiveness against the severe form of the disease reached 97%.
The research further found that four to six months after the second dose, efficacy seemed to decrease to 83.7%, with an average decline of approximately 6% over the past two months. This reduction in immunity had already been observed by the laboratory, making it expand efforts to test the third dose.