AdvertisementEU Regulator: AstraZeneca Vaccine Effective; Blood Clots May Be A Rare Side EffectUpdated April 07, 2021Rachel TreismanfacebookEmailThe European Union's drug regulator on Wednesday announced its findings into the possible connection between AstraZeneca's COVID-19 vaccine and rare blood clots. (NurPhoto via Getty Images)This article was originally published on April 07, 2021.