According to the study, which was conducted on about 20,000 participants in the United States, Astra Zeneca's vaccine should also have an effectiveness of 80 percent for people aged 65 and older.

Virus researcher Ali Mirazimi believes that the study is further proof that the vaccine is effective.

- If there have been any question marks about the protection of the elderly, they should now be gone, he says.

According to Astra Zeneca, an independent committee has studied the presence of blood clots in the US study, including the presence of the unusual form of cebrovascular disease that can cause blood clots in the brain as reported in the EU.

The committee has not found any increased risk of blood clots and according to Astra Zeneca, there is no case in the study of the more unusual form of blood clots in the brain.

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Hear Andreas Heddini, medical director at Astra Zeneca Norden, about the countries' choice to pause the vaccine.

Photo: Tt / SVT

Will find odd side effects

The European Medicines Agency (EMA) and the World Health Organization (WHO) recommend the continued use of the Astra Zeneca vaccine.

Sweden has chosen to continue pausing the vaccine and will leave a message if the vaccination is to resume no earlier than Thursday.

Virus researcher Ali Mirazimi believes that one must go up in numbers in studies if one is to discover odd side effects.

- The only way to find strange side effects is to do huge studies.

With such a large number of people to be vaccinated, strange side effects will appear and some of them serious.

The only thing you can do is see if it is linked to the vaccine and if there is a pattern, he says.