Well i don't know, maybe in Europe we had different articles than in rest of the world. Every media was comparing different vaccines before they arrive and before they become available to the public. Every one mentioned specifically that Janssen was the worst but only required one dose - reason why a lot of young people got it just so they can travel freely because they didn't care much about the covid part and just wanted the certificate. Older people got access to vaccination earlier than others and went for Astra/Pfizer because they were told to be more effective by 15% or so 2 weeks after getting the 2nd dose. Then everyone stopped giving Astra because of that blood clot case and Pfizer/Moderna took over. If this never happened then i must be crazy.