Clinical and survival differences during separate COVID-19 surges: Investigating the impact of the Sars-CoV-2 alpha variant in critical care patients. oleh Andrew I Ritchie, Owais Kadwani, Dina Saleh, Behrad Baharlo, Lesley R Broomhead, Paul Randell, Umeer Waheed, Maie Templeton, Elizabeth Brown, Richard Stümpfle, Parind Patel, Stephen J Brett, Sanooj Soni