COVID-19 vaccine side effects

All vaccines cause side effects. In general, side effects can be described as a sign that the body’s immune system is reacting to the vaccine as expected.

Like other medicines, COVID-19 vaccines can cause side effects. In general, the side effects are mild and temporary, and are common and most often harmless.

The health authorities consider EU approved vaccines to be very safe and well documented. Before a vaccine is approved, it is tested in large clinical trials involving thousands of trial subjects. For a COVID-19 vaccine to be approved, it is crucial that it protects against the illness and that any side effects that the vaccine may cause are not worse than the symptoms or the disease that the vaccine is designed to protect against.

The overall data relating to the vaccines against COVID-19 has been collected over a shorter period of time than normal, because the development stages where carried out in parallel. Even though the vaccines have been developed faster than they normally would, the same thorough review of the documentation has been carried out. The clinical trials of the vaccines against COVID-19 are some of the largest of their kind ever carried out.

However, it cannot be ruled out that unexpected side effects can occur. But experience with the vaccines shows that nearly all of the side effects arising after vaccination do so within the first six weeks and it is very rare that they occur later than that.

The medical authorities monitor the vaccines carefully, including after they have been approved. This is so that they can act quickly if there are signs that there is increased risk with the vaccine. For example, there may be side effects that did not become apparent during the trials or a known side effect that occurs more often than it did during the trials.

Monitoring is achieved through side effects reports from healthcare personnel and from citizens, and by other means.

Common side-effects:

  • Fatigue
  • Headache
  • Muscle pain and joint pain
  • Chills
  • Slight fever
  • Pain, redness and swelling at the injection site

You do not need to contact your health centre if you experience mild side-effects that are considered common side effects. For example, if you experience a slight fever, this is a sign that your immune system is reacting normally.

Serious side effects may occur in rare cases. For example, due to an allergic reaction to the additives in the vaccine. If you have a known and severe allergy, for example to medicines, you should inform the person at the vaccination centre who is responsible for administrating the vaccine.

If you experience serious side effects after you have been vaccinated, you should contact your nearest hospital/health centre. For example, an allergic reaction might be difficulty breathing or a skin rash. A doctor can assess whether the symptoms are due to the vaccine or are caused by something else.

You can contact your nearest hospital/health centre if you are unsure about whether you are experiencing side effects from the vaccination.

The National Board of Health in Greenland (“Landslægeembedet”) participates in the monitoring of likely side effects of the COVID-19 vaccines in Greenland.

Your hospital/health centre is required to report side effects.

You can personally report side effects from the COVID-19 vaccine.

Report side effects from the COVID-19 vaccine (The link goes to

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