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Popular support for the COVID-19 vaccination programme appears unaffected by the pausing of the AstraZeneca vaccine

The willingness to be vaccinated against coronavirus remains unchanged – at 89 per cent –after Danes learned of the reports of rare blood clots, which led to the AstraZeneca vaccine being paused. This is shown by a new study from Aarhus University.

2021.04.08 | Nanna Jespersgård

There is a trust in the healthcare system, but not in the AstraZeneca vaccine, says professor Søren Dinesen Østergaard. Photo: Martin Gravgaard.

Nine out of ten Danes say that they will accept the COVID-19 vaccine when offered. This is the same level as before the AstraZeneca vaccine was paused.

This is shown by a questionnaire-based survey collected by Søren Dinesen Østergaard and co-authors. He is professor at the Department of Clinical Medicine at Aarhus University and affiliated with the Department of Affective Disorders at Aarhus University Hospital, Psychiatry.

"In February 2021, we asked a sample of Danes whether they were willing to be vaccinated against the coronavirus, and 89 per cent replied that they would. This picture was unchanged when the same people were asked again after the pausing of the AstraZeneca vaccine," says Søren Dinesen Østergaard.

The approximately 1,500 participants answered the questions about vaccination for the first time in the period between 4-21 February and then again in the period between 15-25 March. Danish health authorities paused the use of the AstraZeneca vaccine on 11 March – initially for 14 days before extending it until 9 April.

Trust in the healthcare system 

The survey also shows that many Danes feel insecure about the safety of the AstraZeneca vaccine. On a scale from 0-10, where ten is the safest, AstraZeneca scored just over five on average, while the vaccine from Pfizer scored above eight. As could be expected, it is those who do are not willing to be vaccinated who feel most insecure about the AstraZeneca vaccine after the reported blood clots.

"The fact that 89 percent still maintain that they willing to be vaccinated testifies to the high degree of trust in the Danish healthcare system. The extended pause indicates that the healthcare system is thoroughly investigating the cases of blood clots and thus takes our safety seriously. I think the population sees this as due diligence. If anything, it will probably increase confidence in the healthcare system," says Søren Dinesen Østergaard.

On the other hand, the research group is uncertain that all the people who say they are willing to be vaccinated will actually roll up their sleeves for the jab. It is well-known from survey research that 'good behaviour' is often over-reported, because people give what they think is the ‘right’ answer. A phenomenon called social desirability bias.

"If this bias plays a role here, it likely means that the vaccine willingness has been overestimated in this study, but probably to the same extent before and after the pausing of the AstraZeneca vaccine," says Søren Dinesen Østergaard.

Need to rebuild trust in the AstraZeneca vaccine

According to the researchers, the low level of confidence in the safety of the AstraZeneca vaccine is an important signal to the health authorities.

"The results indicate that there will be a need to rebuild the population's trust in the AstraZeneca vaccine if its use is resumed," he says. So far, more than 140,000 Danes have received the AstraZeneca vaccine. The Danish Medicines Agency is currently investigating reports of blood clots in combination with a low number of blood platelets occurring among individuals having received the AstraZeneca vaccine. One case in Denmark has had a fatal outcome, and this case resembles several deaths elsewhere in Europe.

The research results – more information

  • The study is based on data from a questionnaire-based survey carried out by Epinion – who received payment for conducting the survey. In the February wave of the survey, the researchers asked about the willingness to be vaccinated. After use of the AstraZeneca vaccine was paused in March, the same people were again asked about their vaccine willingness. A total of 1,491 survey participants have responded to both waves, and the results are weighted so that they are representative of the Danish population on a number of parameters.
  • The following were partners in the project: Professor Kim Mannemar Sønderskov and Professor Peter Thisted Dinesen from the Department of Political Science at Aarhus University and the University of Copenhagen, respectively.
  • The study is funded by the Novo Nordisk Foundation.
  • Direct link to the scientific article Sustained COVID-19 vaccine willingness after safety concerns over the Oxford-AstraZeneca vaccine published in the Danish Medical Journal.


Professor Søren Dinesen Østergaard
Department of Clinical Medicine at Aarhus University
Department of Affective Disorders, Aarhus University Hospital, Psychiatry
Email: SOEOES@rm.dk
Mobile: (+45) 6128 2753

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