Carl T. Bergstrom. (2021, August 18). 1. There has been lots of talk about recent data from Israel that seem to suggest a decline in vaccine efficacy against severe disease due to Delta, waning protection, or both. This may have even been a motivation for Biden’s announcement that the US would be adopting boosters. [Tweet]. @CT_Bergstrom. https://twitter.com/CT_Bergstrom/status/1427767356600688646

editor, Ian Sample Science. ‘Coronavirus: UK Scientists Identify Drugs That May Help Severe Cases’. The Guardian, 11 December 2020, sec. Science. https://www.theguardian.com/science/2020/dec/11/coronavirus-uk-scientists-identify-drugs-that-may-help-severe-cases.