The Oxford vaccine doesn’t require the same storage protocols as Pfizer’s, which needs specified -70C fridges.
Hospitals and GP surgeries can store the jab in a standard fridge, making it cheaper for other, less well off countries.
Early impressions of the vaccine suggested it was less effective than others coming from the US.
In studies, a two-dose regime delivered just over 60 percent protection, while a half then full dose delivered 90.