COVID-19 vaccines are effective at preventing symptomatic and severe infection among healthcare workers: A clinical review oleh Oliver Galgut, Fiona Ashford, Alexandra Deeks, Andeep Ghataure, Mimia Islam, Tanvir Sambhi, Yiu Wayn Ker, Christopher J.A. Duncan, Thushan I. de Silva, Susan Hopkins, Victoria Hall, Paul Klenerman, Susanna Dunachie, Alex Richter