Reports of suspected adverse reactions to COVID-19 vaccines in Switzerland – update 29
24.02.2023
Reporting period 01.01.2021–22.02.2023
16,855 reports of suspected adverse reactions evaluated – the overall positive benefit-risk ratio of the vaccines remains
Up to 22 February 2023, Swissmedic evaluated 16,855 reports on suspected adverse drug reactions (ADRs).
10,365 (61.5 %) were reported to Swissmedic as “not serious”, while 6,490 suspected cases (38.5%) were classified as «serious».1 The majority of the reports involved more than one reaction. In total, 52, 404 reactions were reported, corresponding to an average of 3.11 reactions per report.
1 The reporting individuals themselves defined whether they classified the cases as serious or not serious. According to international pharmacovigilance practice, this categorisation is revised only for events that were reported as not serious if the ADR is subsequently classified as serious on the basis of further information.
Reports
16,855
Not serious
10,365 (61,5 %)
Reporting rate
0.99
Serious
6,490 (38.5 %)
Vaccine doses
16 981 243
Vaccinated people
6 122 889
Reports classified as serious
Around 38.5 % of cases were classified by the reporters as serious. In these reports, the average age of those affected was 52.7. The most commonly reported reactions were fever, headache, fatigue, shivering, nausea and dizziness. These known reactions also predominated in the cases classified as not serious.
In 236 of the serious cases, a fatality was reported at differing intervals after receiving the vaccine. The average age of those who died was 78.3 years. Despite a temporal association, an in-depth analysis of the data available showed that there were other possible or more likely causes of the reported deaths.
Primary reporter
The Therapeutic Products Act (TPA) requires healthcare professionals to report serious adverse effects and as yet unknown effects to Swissmedic. 7, 497 (45%) reports were submitted by healthcare professionals. Members of the public may voluntarily report suspected side effects of medicines: 9,314 reports (55%) were received directly from those affected, i.e. the patients, or their relatives.
Age and gender of persons affected
Most of the people affected (66.8%) were aged between 18 and 64 years (50.1 years on average). 19.7% were aged 65 or older, while 1.1% were in the 12 to 17 age group.
10,342 (61.5 %) of the reports concerned women, 5,909 (35.1%) of the reports concerned men. In a few reports no age or gender was specified.
Evaluations of individual vaccines
11,641 (69%) of the reports involve Moderna’s COVID-19 vaccine Spikevax® (with approx. 63% of the vaccine doses administered, this is the most widely used vaccine in Switzerland) while 4,696 (28%) are associated with Pfizer/BioNTech’s Comirnaty® (approx. 37 % of administered vaccine doses). In some cases, the vaccine was not specified.
Number of reports by vaccine and dose
Vaccine
Total reports
of which non-serious
of which serious
Total vaccine doses * [2]
Spikevax® (Moderna) [1]
8,976 (53.3 %)
5,774 (55.7 %)
3,202 (49.3 %)
10,519,274 (62.9 %)
Spikevax® (Moderna) 3rd, 4th and 5th vaccination
2,414 (14.3%)
1,714 (16,5 %)
731 (11.3 %)
Spikevax® (Moderna) Bivalent Original / Omicron BA.1
251 (1.5%)
194 (1.9 %)
57 (0.9 %)
Comirnaty® (Pfizer/BioNTech) [1]
4,103 (24.3 %)
2,156 (20.8 %)
1,947 (30.0 %)
6,234,821 (36.7 %)
Comirnaty® (Pfizer/BioNTech) 3rd and 4th vaccination
565 (3.4 %)
303 (2.9 %)
246 (3.8 %)
Comirnaty® (Pfizer/BioNTech) Bivalent Original / Omicron BA.1
28 (0.2)
14 (0.1)
14 (0.2)
COVID-19 Vaccine Janssen [1]
166 (1.0 %)
86 (0.8 %)
80 (1.2 %)
63,730 (0.4 %)
Nuvaxovid® (Novavax)
7 (0.0)
0 (0.0 %)
1 (0.0 %)
3,427 (0.0 %)
Unknown
345 (2.0 %)
149 (1.4 %)
196 (3.0 %)
Total
16,855 (100 %)
10,365 (100 %)
6,490 (100 %)
16,981,243 (100 %)
[1] Basic immunisation (two doses)
[2]Basic immunisation (two doses), booster and bivalent vaccines
* Switzerland and Principality of Liechtenstein, 21.12.2020–21.02.2023 (Source: FOPH)
Reported vaccine reactions and affected organ systems by vaccine
In the period examined, Swissmedic received only a small number of reports of suspected causal links with the Nuvaxovid vaccine (see table).
The reports of adverse reactions received and analysed to date do not alter the positive benefit-risk profile of the COVID-19 vaccines used in Switzerland. This largely confirms their known side effects profile. Known side effects of COVID-19 vaccines are listed in the continually updated medicinal product information texts published on www.swissmedicinfo.ch.
The reports of suspected adverse drug reactions (ADR) to COVID-19 vaccinations are evaluated in collaboration with the regional pharmacovigilance centres and in particular with the Ticino reference centre (EOC cantonal hospital authority).
Next update
According to the World Health Organization (WHO), over 13 billion doses of coronavirus (SARS-CoV-2) vaccine had been administered worldwide as at 14 February 2023. Thanks to the widespread use of COVID-19 vaccines, it is possible to continually gather up-to-date and comprehensive data on the risk-benefit ratio and include information on as-yet unknown rare side effects in the medicinal product information. The vaccines authorised in Switzerland reliably reduce the risk of contracting severe COVID-19.
For some time now, Swissmedic has been receiving far fewer reports of suspected adverse reactions than when vaccination first started and will therefore provisionally cease publishing regular updates on reported adverse reactions to COVID-19 vaccines in their current form. However, the Agency will continue to monitor COVID-19 vaccines closely and new information on risks and safety signals will be communicated via the usual channels (website, DHPCs).
Information from Swissmedic on individual safety aspects
Post-vaccine syndrome
In the context of COVID-19 vaccinations, certain highly heterogeneous and generally prolonged symptoms that have occurred in vaccinated individuals with a temporal relationship to vaccination are also referred to as “post-vaccine syndrome”. The symptoms reported, which may result in significant impairment for some of the individuals affected, cover a broad spectrum and overlap in some cases with long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).
Swissmedic treats reports of such cases very seriously and continually reviews the latest drug safety findings and medical science literature. At present, there is no recognised standard definition of post-vaccine syndrome. For example, it is unclear which symptoms can be ascribed to post-vaccine syndrome, how long these symptoms have to persist before patients can be suspected to have the syndrome, and how it can be distinguished from long COVID in the light of the high rate of past SARS-CoV-2 infections. Given this lack of clarity, it is also not possible to provide reliable information on the number of reports received that involve the syndrome. Swissmedic appeals to medical professionals reporting suspected cases of post-vaccine syndrome to provide details of the patient’s previous medical history and the diagnostic procedures followed so that it has a larger amount of medical information to evaluate. Swissmedic is also consulting partner authorities in other countries on the issue and will provide information as soon as new and relevant findings are available.
Reporting a general adverse reaction to a medicinal product or a suspected adverse reaction in connection with a COVID-19 vaccine
Private individuals can now submit all reports of suspected adverse reactions to human medicinal products to Swissmedic via a web form. You can report an adverse drug reaction for yourself or on behalf of another person, such as a child or relative.
Internationally binding criteria exist for classifying a suspected adverse reaction to a drug or vaccine as "serious". It is always classified as serious if the suspected adverse reaction was life-threatening, resulted in hospitalisation or prolonged an existing hospitalisation, or in cases involving a fatal outcome. Cases are also considered to be serious if they have resulted in disability or permanent damage that caused substantial disruption to a person's ability to conduct normal life functions. If the administration of a drug to a pregnant woman has led to an adverse reaction or damage in the newborn child, this situation should always be classified as serious. Another criterion for classifying a case as serious is whether it is described as "medically important" or resulting in "temporary severe impairment". This criterion often leads to misunderstandings. It refers to cases in which the affected individuals were specifically at risk and required a medical intervention in order to prevent serious damage in terms of the above-mentioned criteria.
Criteria for a serious adverse reaction to a drug or vaccine:
Death
Life-threatening
Hospitalisation or prolongation
Persistent damage or disability
Congenital anomaly
Medically important / temporary severe impairment (medical intervention required)
Occasionally, the criterion of "medically important/temporary severe impairment" is checked inappropriately in reports of suspected reactions. Thus, for example, a person can experience a fever after a vaccination and feel ill for several days, or have severe headaches and joint pains, and yet the case is not "serious" according to the categories described above. Although such symptoms are obviously "severe" or "pronounced" for the individual concerned, and thus very unpleasant and stressful, the crucial aspect of a specific medical threat is lacking.
As regards reports of suspected adverse reactions submitted to Swissmedic, the reporting individuals themselves decide whether to classify the effect as serious and according to what criterion. Even if the information on seriousness proves to be incorrect on inspection, the classification is not usually changed by Swissmedic according to the standard international procedure in drug safety: this means that a case reported as "serious" is not downgraded to "non-serious". A correction is made only in exceptional cases, and then only for the purpose of "upgrading". This may be the case, for example, if an adverse reaction was incorrectly classified as "non-serious" on the basis of further information in the report, and is clearly classified as "serious" by Swissmedic.
Given the methodology of the spontaneous reporting system, the following factors need to be taken into account when interpreting the data presented here:
The figures provided relate to suspected reactions reported to Swissmedic and entered in the database after being reviewed.
All the reactions reported are suspected cases. In individual cases it has not been ascertained whether the reported reaction was only observed in a temporal relationship with the vaccination or was actually caused by it.
The number of suspected cases for each vaccine can depend greatly on how many people received this vaccine in the period in question.The nu mber of vaccination reactions could be higher than the number of reports. Depending on the authorised use (e.g. age group, high-risk individual) and the latest vac cination recommendations, certain vaccines are more frequently administered to people with a serious preexisting condition.
This can influence the occurrence of certain reactions which, however, are only indirectly related to the particular vaccine.
The figures for suspected cases of vaccination reactions are just one of many elements used to monitor the risk-benefit profile of vaccines. Only a detailed scientific evaluation of all the available data will enable the correct conclusions to be made about a vaccine’s safety profile.
