Researchers explore mixed vaccine shots as world faces around 4,000 Covid-19 variantsEuropost
The world faces around 4,000 variants of the virus that causes Covid-19, prompting a race to improve vaccines, Britain said on Thursday, as researchers began to explore mixing doses of the Pfizer and AstraZeneca shots, Reuters reported.
“All manufacturers, Pfizer-BioNTech, Moderna, Oxford-AstraZeneca and others, are looking at how they can improve their vaccine to make sure that we are ready for any variant - there are about 4,000 variants around the world of Covid now,” British Vaccine Deployment Minister Nadhim Zahawi told Sky News.
Britain on Thursday launched a trial to assess the immune responses generated if doses of the vaccines from Pfizer and AstraZeneca are combined in a two-shot schedule. The British researchers behind the trial said data on vaccinating people with the two different types of vaccines could help understanding of whether shots can be rolled out with greater flexibility around the world. Initial data on immune responses is expected to be generated around June. 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.
While thousands of variants have arisen as the virus mutates on replication, only a very small minority are likely to be important and to change the virus in an appreciable way, according to the British Medical Journal.