Safety and immunogenicity of a live-attenuated influenza virus vector-based intranasal SARS-CoV-2 vaccine in adults: randomised, double-blind, placebo-controlled, phase 1 and 2 trials thelancet.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from thelancet.com Daily Mail and Mail on Sunday newspapers.