The AstraZeneca Oxford COVID-19 vaccine (ChAdOx1 nCoV-19 and also known as AZD1222) now undergoing Phase III clinical trials, has already undergone rigorous testing to ensure the highest standards of quality and safety. Now a team at Bristol University has used recently developed techniques to further validate that the vaccine accurately follows the genetic instructions programmed into it by the Oxford team. This novel analysis provides even greater clarity and detail about how the vaccine successfully provokes a strong immune response.