In this article22UA-DEPFEKathrin Jansen, Pfizer Inc, poses for a portrait in one of her labs in Pearl River, New York.Carlo Allegri | ReutersThe mRNA technology used to develop the Pfizer-BioNTech Covid-19 vaccine could also help create "more potent" seasonal flu shots, Kathrin Jansen, head of Pfizer's vaccine research and development, told CNBC.How well flu vaccines