WHILE Pfizer, BioNTech and Johnson & Johnson have raised the strong probability for the need of an extra dose of vaccine to provide enough immunity against Covid-19 variants, AstraZeneca says it is not yet sure whether a booster dose of its vaccine will be necessary for continued protection against the coronavirus.
As AstraZeneca CEO Pascal Soriot explained on news channel CNBC recently, “There are two dimensions to this immunity – antibodies [which] decline over time, but the second, very important dimension of vaccination is the so-called T-cells. They tend to protect people against severe disease, but they also provide durability.