Thousands of variants have been documented as the virus mutates, including the so-called British, South African and Brazilian variants which appear to spread more swiftly than others. British Vaccine Deployment Minister Nadhim Zahawi said it was very unlikely that the current vaccines would not work against the new variants. "Its very unlikely that the current vaccine won't be effective on the variants whether in Kent or other variants especially when it comes to severe illness and hospitalisation," Zahawi told Sky News. The trial will examine the immune responses of an initial dose of Pfizer vaccine followed by a booster of AstraZeneca's, as well as vice versa, with intervals of four and 12 weeks. Matthew Snape, an Oxford vaccinologist who is leading the trial, said mixing different shots had proven effective in Ebola vaccine schedules, and though the new trial mixed vaccine technologies, it could also work.
