1. Covid-19: European countries suspend use of Oxford-AstraZeneca vaccine after reports of blood clots
2. European Medicines Agency. Covid-19 vaccine AstraZeneca: PRAC investigating cases of thromboembolic events—vaccine’s benefits currently still outweigh risks: update. Mar 2021. https://www.ema.europa.eu/en/news/covid-19-vaccine-astrazeneca-prac-investigating-cases-thromboembolic-events-vaccines-benefits.
3. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK