When Covid struck and the quest for a vaccine began, the team at Oxford had a head start in that we were already working with the harmless common cold virus on which the AstraZeneca vaccine is based. ChAdOx — a contraction of ‘chimpanzee’, from which the virus was isolated, ‘adenovirus’ and ‘Oxford’ — is also being used to target diseases such as malaria, rabies, zika and Mers. The virus can get into our cells, but it cannot cause infection or replicate, which means it doesn’t spread through our body or from person to person. Instead, we use it to deliver what we want the body to see and respond to — which in the case of Covid-19 is the spike protein of the coronavirus.
I recommend the article above to you. Reading something genuinely informative while aimed at a layman demonstrates how utterly denuded most media coverage is.