The European Medicines Agency on Thursday declared that the COVID-19 developed by AstraZeneca and Oxford University is "safe and effective," giving a nod of approval for European nations to resume using the inoculation.

Why it matters: It comes after vaccination was halted across much of Europe, following reports that a small number of patients who received the vaccine experienced blood clots. EMA Executive Director Emer Cooke said Thursday the vaccine benefits "outweigh the possible risks."

• Yes, but: Cooke said the EMA, following its trials "still cannot rule out definitely a link between [blood clot] cases and the vaccine," and is launching additional investigations and studies.
• Cooke said the EMA recommends raising awareness of the possible risks by making sure they're included in product information about the vaccine.
• "Given that thousands of people in the EU die every day ... it really was crucial for EMA to review rapidly and thoroughly all the available evidence. We made this review our highest priority.

What they're saying: "When you vaccinate millions of people its inevitable that rare or serious instances or illnesses will occur in the time immediately following the vaccination," Cooke said.