Over the 8 months from 1 January and 1 September 2021, close to 10 million doses (9.7 million) of the Moderna (6.4 million) and Pfizer/BioNTech (3.3 million) Covid-19 vaccines were given to more than 5 million people in Switzerland. Over this time there were 6,603 official reports of side effects, which represents 0.07% of doses. The majority of reports concerned women (66%).
The top five adverse reactions reported were discomfort, swelling or reddening at the injection site (1,930), fever (1,590), headache (1,413), fatigue (1,085) and the chills (910).
Of the 6,603 reports of side effects, 2,161 were considered serious, a rate of 0.02% of vaccinations. The average age of those reporting serious side effects was 59.
Over the 8 months, 137 of those reporting serious side effects died. This group was 80 years old on average and there was no concrete evidence linking these deaths to the vaccinations, only temporal correlation.
By June 2021, myocarditis, an inflammatory heart disease caused primarily by viruses, had been reported in 6 vaccinated people in Switzerland, and inflammation in the covering around the heart was reported in a further 6. Myocarditis has been associated with mRNA vaccines, such as the Moderna and Pfizer/BioNTech vaccines used in Switzerland.
However, the link between mRNA vaccines and these conditions remains unclear. Switzerland’s 12 reported cases among 5 million vaccine shots is a rate of roughly 1 per 400,000. The normal (background) incidence of myocarditis in the population is 88 per 400,000, far higher than the 1 per 400,000 reported among those vaccinated.
A preliminary US study published in July 2021 suggests that those most affected by myocarditis are 6 times more likely to suffer from it after a Covid-19 infection than after a vaccination. The study found rates of myocarditis in young males with Covid-19 to be as high as 180 per 400,000. Another US study published in September 2021, suggests that catching Covid-19 comes with a risk of myocarditis 16 times higher than with mRNA vaccines.
According to the US CDC, most patients who receive care for myocarditis respond well to treatment and rest and quickly feel better.
Swissmedic noted in its report that the reports it had received of vaccination side effects are incomplete and suspected. It said that it is not possible to establish whether a reported reaction merely coincided with the vaccination or was actually caused by it.