The country’s medicines regulator is set to give the green light this week, reports say. It comes after several other coronavirus vaccines gained approval in various parts of the world, among them shots from Pfizer-BioNTech, Moderna and Sinopharm. In the UAE, the Pfizer-BioNTech and Sinopharm vaccines are already being used. Here, we look at the Oxford-AstraZeneca vaccine, how it differs from other vaccines and what could be done to improve it. How does it work? The vaccine is given in two doses, 28 days apart. Researchers extracted genetic instructions for building coronavirus spike proteins – the structures on the outside of the virus that it uses to enter human cells – and inserted them into another virus called an adenovirus. The host adenovirus used in the vaccine is a virus that causes the common cold in chimpanzees.