Questions and answers on COVID-19 vaccines
Medicines agencies around the world are collaborating on the authorisation and monitoring of COVID-19 vaccines. Once the vaccines have been authorised, drug regulatory authorities around the world follow up on them by monitoring side effects. Read more in our questions and answers on COVID-19 vaccines.
Questions and answers on COVID-19 vaccines
The vaccines’ efficacy
How effective are the vaccines?
Phase 3 trials with thousands of trial participants have established that far fewer of those who were vaccinated got COVID-19 compared to those who were given a placebo or a control vaccine. The efficacy varies from vaccine to vaccine.
For how long does the vaccine protect against disease?
Because the vaccine has been developed so fast, it has not been possible to study its efficacy over a long-term period.
Is the vaccine equally effective in any population?
The vaccines are authorised based on trials with many different populations including elderly people and those in risk groups. However, these trials have only to a very limited extent included pregnant women and children, and therefore, we do not know much about the efficacy in these target groups.
On the page about authorised vaccines, you can read more about the groups the vaccines have been tested in. Look for the “Efficacy ”sections.
Are people contagious after vaccination?
There is still not enough data from studies to determine if vaccinated people with no symptoms of COVID-19 are still contagious. Also, the possibility of transmission by hand makes it important that people who have been vaccinated continue to follow the health guidance on social distancing and hygiene.
Do the vaccines protect against the virus mutations that have spread in, for example, the United Kingdom and South Africa?
Who can be vaccinated?
Should people with allergies say no to vaccination due to the risk of allergic reactions?
People with allergies can generally be vaccinated, unless they have a known allergy to the vaccine’s active substance or one or more of its adjuvants (“helping agents”). If so, they should avoid COVID-19 vaccination. Persons who have previously experienced an allergic reaction after vaccination or injection with a medicine should be evaluated by a doctor before vaccination as they have a higher risk of allergic reactions.
This evaluation can be made by their doctor before vaccination, and the doctor might need to ask the advice of another medical expert.
Should pregnant or breast-feeding women have the vaccine?
If you are pregnant or breastfeeding, you may also be vaccinated against COVID-19, as data from women who have been vaccinated show that vaccination is just as effective and safe as for people in the same age group.
As a pregnant woman, you are at increased risk for severe COVID-19. If you are breast-feeding, you have the same risk of COVID-19 as the rest of the population of similar age.
You can read more on the Danish Health Authority's website (in Danish only).
Does the vaccine impair fertility?
There is no indication that fertility is affected by COVID-19 vaccination. Animal studies were undertaken for some of the vaccines. These studies showed that there were no vaccine-related effects, neither on the female animals’ fertility and pregnancy nor on the foetus’ development before or after birth. Read the summaries of product characteristics of the individual vaccines for further details.
Can persons suffering from an auto-immune disease be vaccinated?
Are there any types of medicines that should be taken cautiously before vaccination?
Should the vaccine be avoided if you have had Botox?
Persons who have previously been treated with Botox can be vaccinated.
Is it possible to get COVID-19 from vaccination?
No, this is not possible. The vaccines do not contain corona virus. You might experience transient side effects such as soreness at the injection site, headache and perhaps fever. These are signs that your body is reacting to the vaccine, and that the immune system has been activated and is ready to defeat the target virus if entering the body.
How do we know that the new mRNA vaccine technology is safe?
The mRNA vaccine has been tested in at least 35,000 people without any of them developing serious side effects. Once mRNA has constructed the spike protein, the body breaks down the mRNA just as it does with its own mRNA. All COVID-19 vaccines are monitored throughout the world to watch for the development of unexpected unacceptable side effects.
Do the vaccines cause side effects?
All medicines have side effects; the COVID-19 vaccine is no exception. The decisive point is that the vaccines’ potential side effects must not be worse than the symptoms and the disease that the vaccines are intended to prevent. This is being monitored carefully by drug regulatory authorities around the world.
What side effects have been observed for the vaccines?
The most common side effects of the COVID-19 vaccines that were observed in the trials were generally mild or moderate in character and improved or disappeared within a few days. These would include:
- Pain and swelling at the injection site
- Muscle and joint pain
As with all vaccinations, a small risk of extremely rare allergic reactions and so-called anaphylactic reactions were also observed for the COVID-19 vaccines. These reactions could be serious if they are not treated immediately.
The known side effects of the individual COVID-19 vaccines appear in the product information (package leaflet and summary of product characteristics) for each of the vaccines. Read more about the side effects reported for the vaccines.
Who can report side effects?
Both healthcare professionals and people in general can report suspected side effects to the Danish Medicines Agency. Only a suspicion is needed to report. You can make a report even if you only suspect the symptoms to be caused by a vaccine – you do not have to be sure that it is related. Please remember that it is not necessary to report or contact your doctor about common mild undangerous side effects such as discomfort, redness at the injection site, mild fever and muscle soreness.
In the first two years after the vaccines have been rolled out, doctors, dentists, prescribing pharmacists and midwives must report any suspected side effects experienced by their patients to the Danish Medicines Agency. After this period, the reporting obligation only concerns suspected serious or unexpected side effects.
How is it assessed if a suspected side effect is caused by the vaccine?
A reported suspected side effect does not necessarily mean that there is an established link between the vaccine and the reported side effect. However, individual reports of suspected side effects could be a signal of new or changed risks that need to be investigated in detail.
As part of this, the Danish Medicines Agency checks if other diseases or circumstances are more likely to explain the symptoms. We use the World Health Organization’s (WHO’s) classification to assess suspected side effects in connection with vaccination. The Danish Medicines Agency registers all reports of suspected side effects in a database of side effects, and they are hereafter included in the continuous safety monitoring. When a side effect is registered, we assess if we need to obtain additional information for us to have enough details to assess if there is an association between the symptoms and the vaccination.
What will the Danish Medicines Agency do if new side effects are identified for one of the vaccines?
The drug regulatory authorities will intervene if new or changed risks are identified for the vaccines. Like for other medicines, they may:
- Add new side effects or recommendations in the product information.
- Restrict who the vaccines are authorised for.
- Suspend the authorisation.
Is it possible that the COVID-19 vaccines can have side effects not presenting before a longer period of time?
The COVID-19 vaccines have been authorised on the basis of extensive safety and efficacy data from trials of each vaccine with up to 40,000 trial participants whose health status was monitored for an average of six weeks.
It cannot be ruled out that unexpected side effects may appear, but we know from other vaccines that almost all side effects after vaccination occur within the first six weeks and that it is very rare for them to occur later.
The drug regulatory authorities monitor the vaccines closely after they have been authorised to be able to respond should it turn out that a vaccine is associated with an increased risk, such as side effects that did not emerge during the trials or known side effects that appear to occur more frequently than in the trials.
Is compensation available for people who may experience side effects or long-term effects?
As with other types of medicines, you may be entitled to compensation from the Danish Patient Compensation Association.
Do manufacturers of COVID-19 vaccines have the same liability towards European citizens as they have for other types of medicines?
The contracts on the procurement of COVID-19 vaccines negotiated by the European Commission with vaccine manufacturers on behalf of the EU member states are fully compliant with the Community legislation and the directive on product liability.
However, the rules on product liability makes no difference to the individual patient as patients have the right to compensation for rare and serious side effects, regardless of whether the manufacturer can be held liable for a product defect. It is the state that pays compensation to the patient, and the state can subsequently assess if it will file a product liability claim against the manufacturer to cover the costs of compensation.
The vaccines’ ingredients
Are eggs contained in the COVID-19 vaccines?
Do the vaccines contain aluminium?
Does the vaccine contain formaldehyde/formalin?
Do the vaccines contain preserving agents?