Many prefer to be vaccinated with Pfizer / Biontech because they have heard of fewer side effects. The official statistics also suggest that there is more reaction to Moderna. But is the assumption correct? Questions and answers.
How do you know what side effects Covid 19 vaccines have? The national pharmacovigilance center of the therapeutic products authority Swissmedic receives reports on side effects of drugs. It works with the WHO International Center for Drug Safety. This is important in order to gain access to the international database in which side effects on medicines are collected around the world.
Bi-weekly updates of the numbers
Every two weeks, Swissmedic publishes the reports of suspected adverse effects of the two Covid-19 vaccinations in a bulletin on the homepage – the current figures, Link opens in a new window are from June 18th. By then around 7,800 had been reported, around 2,950 reports were evaluated, of which just under 65 percent were not classified as serious. The number of people vaccinated (at least 1 dose) at this point in time was a good 3.76 million.
Swissmedic is also observing that there are more reports than ever about the Covid 19 vaccines. This can be explained on the one hand by the fact that never before have so many people been vaccinated so quickly – but also by the great public attention. It is quite conceivable that false reports were also received from private individuals. Swissmedic would then compare the reports with available information from the hospitals (place of vaccination, time, etc.). And you can now benefit from many years of experience in evaluating reports on side effects of other drugs and vaccines.
Why is it important to record in the database? By consistently forwarding this information, previously undetected risks can be identified. This is because the effects on a larger group than those in the study can only be observed after a drug has been launched on the market.
What is reported? According to the Swiss Medicines Act, serious, previously unknown and other medically important adverse effects must be reported. It is enough if there is a suspicion that the drug is related to an effect. In addition, each message is viewed individually and clarified if necessary. This can even be an autopsy order in the event of death.
What are “serious” side effects?
The classification of side effects is defined internationally, as Alex Josty from Swissmedic explains. Events classified as serious include hospitalizations, permanent disabilities or deaths. Patients report events to Swissmedic that they consider serious (including, for example, high fever, pain or severe nausea). As a rule, known, common side effects such as reactions at the injection site (pain, redness and swelling), but also headache, tiredness, muscle and joint pain and general symptoms such as chills, feverish feeling or a slight fever are not serious.
Who reports the side effects? Doctors and pharmacists are legally obliged to do so. Most of the reports (currently around 83 percent) come from these specialists. Patients are allowed to register voluntarily, using the form , Link opens in a new windowor to the doctor. So far, almost 500 reports have been received from private individuals, more than two thirds from women. Swissmedic explains this with the fact that – especially at the beginning of the vaccination campaign – more women were vaccinated because of the age pyramid. In addition, studies indicate that women are less reluctant to see a doctor and report side effects.
However, Swissmedic also assumes that not all side effects are reported. “There is an unreported number,” says media spokesman Alex Josty. “It is probably higher rather than lower.”
Does that happen then? The pharmacovigilance team, made up of medical specialists, checks whether the dozen or so reports are complete every day, supplements them if necessary after asking the patient and doctor, and arranges them according to the vaccine and severity of the reaction. It checks them for new risks and compares them with reports abroad. Each report is fed into the WHO statistics.
Are there really fewer side effects at Pfizer / Biontech? If you look at the latest figures, there are numerically more side effects reported for Moderna. More serious cases are also reported at Moderna. The fact is, however, that both vaccines have roughly the same number of side effects in the clinical studies, explains the Swissmedic spokesman. The fact that one hears more about Moderna side effects is probably also due to the fact that more Moderna vaccines are inoculated. The number of reports per vaccine would roughly correspond to the amount inoculated in Switzerland.
More headaches with Pfizer, “Covid arm” by Moderna
Similar symptoms are reported for both mRNA vaccines approved in Switzerland, according to Swissmedic, these are in advance: headache, fever, muscle pain, chills, pain at the injection site, fatigue. For Pfizer, however, headaches are reported more often, for Moderna more frequent pain at the injection site and the so-called “Covid arm”.
And finally, side effects would be perceived differently from person to person. However, Swissmedic is grateful for every single report. “It helps us to learn and gain new knowledge about side effects of vaccinations.”