Getting vaccinated against COVID-19

8. Vaccines

Types of vaccines

mRNA vaccines

 The mRNA vaccine contains a part of the genetic segment of the coronavirus called “messenger RNA” or “mRNA”. The RNA code is found in tiny droplets of fat. The messenger RNA instructs cells to create a harmless piece of protein, which resembles the outside layer of the coronavirus. When the immune system encounters this protein piece, it recognizes that it does not belong there, and therefore creates the antibodies to fight it.  Through this process, our immune system is then prepared in case of infection and our bodies will be able to rapidly eliminate any coronavirus encountered. The messenger RNA injected with the vaccine is broken down and disappears completely after 1 – 2 days. 

The Federal Office of Public Health (FOPH) and the Federal Commission for Vaccinations (FCV) recommend that people who are pregnant, breastfeeding or suffering from an immune deficiency caused by medication or disease be vaccinated with an mRNA vaccine.

In Switzerland, the mRNA vaccines currently used in the COVID-19 vaccination campaign are the monovalent vaccins Comirnaty® manufactured by Pfizer/BioNTech and Spikevax® manufactured by Moderna. The Moderna Spikevax® bivalent vaccine and Comirnaty® bivalent vaccine from Pfizer/BioNTech are also available.


Difference between monovalent and bivalent vaccines?

In Switzerland, monovalent vaccines are generally used for primary vaccination against COVID-19 (but a bivalent vaccine can also be used). Bivalent vaccines are available for booster vaccination. These are all mRNA vaccines.

  • The monovalent COVID-19 vaccines used in Switzerland are the Comirnaty® vaccine manufactured by Pfizer/BioNTech and the Spikevax® vaccine manufactured by Moderna. They target only the original strain of coronavirus. They continue to provide good protection against severe disease and hospitalization even with the currently circulating Omicron variants. For this reason, they can still be administered as part of the booster vaccination in autumn 2022 for all persons aged 16 years or older. 
  • Bivalent mRNA vaccines available in Switzerland (Spikevax® vaccine from Moderna and Comirnaty® vaccine from Pfizer/BioNTech) target the initial strain ("Wuhan") and the Omicron BA.1 variant.  
Booster vaccination can be done with a different vaccine (Pfizer/BioNTech or Moderna bivalent) than the one received for the previous dose(s).


Differences between the Pfizer/BioNTech vaccine and Moderna vaccine 

There are few differences between the Pfizer/BioNTech's COVID-19 vaccine Comirnaty® and Moderna's Spikevax® namely that the vaccines contain different additives.

Many elements are similar or identical for both vaccines. The similarities are the following:

  • Both are mRNA vaccines.
  • Both have high efficacy.
  • Both products are well tolerated.
  • Both products contain polyethylene glycol (PEG). Vaccination against COVID-19 is contraindicated if you have a known strong allergy to this substance.

Primary vaccination of people under 30 years of age should be carried out with Pfizer/BioNTech's Comirnaty® vaccine. For all persons over 30 years of age, Spikevax® from Moderna is recommended, but it is possible to be vaccinated with Comirnaty® from Pfizer/BioNTech. 

The booster is recommended with Moderna's Spikevax® and the Pfizer/BioNTech Comirnaty® bivalent mRNA vaccines. Booster vaccination can be done with a different vaccine (Pfizer/BioNTech or Moderna bivalent) than the one received for the previous dose(s). 


Other vaccines

Other vaccines provided in Geneva are the Johnson & Johnson's Janssen® vaccine, which works using a viral vector mechanism, and the Novavax's Nuvaxovid® vaccine, which is a protein vaccine (a protein from the virus rendered harmless).

These vaccines offer an alternative in case of medical contraindication or refusal of the mRNA vaccine. They are not however recommended for pregnant or breastfeeding women.


Janssen® vaccine

The Janssen® vaccine is not an mRNA vaccine. It works using a viral vector mechanism.

The Janssen® vaccine is no longer recommended for the 2022 autumn-winter booster vaccination campaign.  People who wish to be vaccinated with a non-mRNA vaccine will instead opt for Nuvaxovid®.

The Janssen® vaccine is not recommended for immunosuppressed persons, pregnant or breastfeeding women.

Use of the Janssen® vaccine is contraindicated in persons with a severe allergic reaction to any of the components of this vaccine, with a known or probable immediate sensitisation to polysorbate 80 (E433) and with a history of capillary hyperpermeability syndrome.

In case of doubt, it is advisable to consult a competent medical doctor.


Nuvaxovid® vaccine

The Nuvaxovid® vaccine produced by the Novavax laboratory is available at the vaccination centre of the University Hospitals of Geneva. Nuvaxovid® is the first protein-based vaccine against COVID-19 available in Switzerland. Nuvaxovid® contains neither genome nor RNA. It is based on a more conventional technology already used for vaccines against influenza, hepatitis B, meningitis or whooping cough.

This protein vaccine offers a good protection against COVID-19 diseases. Booster vaccination (homologous and heterologous) with Nuvaxovid® demonstrates a good immune response, including against the BA.5 sub-variant. As this vaccine is less specific to one SARS-CoV-2 variant, Nuvaxovid® produces a somewhat broader immune response than monovalent mRNA vaccines.

  • The Nuvaxovid® vaccine is currently not recommended for pregnant or breastfeeding women (lack of data)
  • The Nuvaxovid® vaccine is currently not recommended for immunosuppressed persons unless there is a medical contraindication to mRNA vaccines
  • Allergy to any of the components of this vaccine, in particular known or likely immediate sensitisation to polysorbate 80 (E433), saponin or Matrix-M adjuvant

Persons who, for medical reasons, cannot receive an mRNA vaccine or who refuse to receive it, may receive booster vaccination with Nuvaxovid® vaccine if they do not belong to one of the groups for whom this vaccine is not recommended or contraindicated. They may register on the online registration platform and tick the adequate Nuvaxovid® box.




Possible benign side effects of mRNA vaccines

Like most vaccines, mRNA vaccines can have mild side-effects. Such effects can appear on the day of vaccination or the day after. A few examples of some these are:

  • Slight discomfort around the area of injection (swelling, redness, pain)
  • Tiredness
  • Headaches
  • Stiffness
  • Other mild forms of inflammatory reactions caused by the activation of the immune system. 

These reactions are normal and not dangerous. They may last between 1 and 3 days. They can be treated with paracetamol and do not need medical care. Pain can be treated with a cold pack. 

Moreover, there is no correlation between the presence (and degree of intensity) of side effects following a vaccine and its effectiveness on the immune system.


Undesirable side effects due to mRNA vaccines

Reporting serious side effects
All serious side effects must be reported either by mentionning them to one's GP or by filling in the Swissmedic form.. The Swissmedic reporting service examines all reports.

1) COVID arm

* A temporary inflammation at the injection spot has occasionally been observed after the COVID-19 vaccination called "COVID arm". This consists of redness and swelling, sometimes significant, which appears on the arm in where the vaccine was administered. These reactions usually occur about a week after vaccination. They are unpleasant but harmless, disappear after a few days without treatment, and have no long-term consequences. You can apply a cold pack to reduce the effects. If the discomfort is too great, contact your doctor, who will tell you how to alleviate it specifically.


2) A strong immune response suggesting that you may have been exposed to SARS-CoV-2.

It is possible that you have developed an asymptomatic form of COVID-19 and that you are therefore partially immune. This can be confirmed through a serology test (expense not covered by the Confederation)


3) Allergic reaction to one of the components of the vaccine

Very rarely, severe side effects are observed, for example an allergic reaction (risk of less than 1 in 100,000 people). This reaction occurs within minutes of the injection and is quickly controlled with immediate medical attention. For this reason, vaccinated persons are monitored for at least 15 minutes after the injection.

For the vaccines used in Switzerland, the components that can cause an allergic reaction are polyethylene glycol (PEG)/macrogol in the Pfizer/BioNTech and Moderna vaccines and/or tromethamine in the Moderna vaccine.

If you have had strong symptoms (allergic/anaphylactic reaction, which usually appears immediately after vaccination with itching, swelling of the palms of the hands or soles of the feet, eyelids, oral mucosa, lips or tongue, red papules, breathing problems, shortness of breath, coughing, gastrointestinal problems, dizziness, feeling faint), it is recommended that you discuss this with your doctor or an allergist.

To find out if you are indeed allergic to a component of an mRNA vaccine, it is advisable to consult your GP, who will assess whether a consultation with a specialist is recommended in your situation.

You can also consult the recommendations for vaccination against COVID-19 in people with allergic diseases of the Swiss Society of Allergology and Immunology. 

Available in French:  Recommandations pour la vaccination contre COVID-19 chez les personnes atteintes de maladies allergiques de la Société suisse d'Allergologie et d'immunologie.

If you are indeed allergic to one of the components of an mRNA vaccine and you reside in Geneva, you may opt, in consultation with a specialist, for the Johnson & Johnson's Janssen® vaccine or the Novavax Nuvaxovid® vaccine, by registering on the vaccination platform and ticking the adequate box.
4) Inflammation of the heart muscle (myocarditis) or pericardium

In very rare cases, inflammation of the heart muscle (myocarditis) or pericardium has been observed shortly after vaccination. They occur between the 4th and 14th day after vaccination, in 80% of cases after a second dose. A link with vaccination is currently considered possible. Most of these cases were mild and easily treated. The maximum risk of post-vaccination myocarditis/pericarditis is estimated at 6 cases/100,000 young men vaccinated, i.e. six times less than after COVID. Typical symptoms of inflammation of the heart muscle are chest pain, difficulty in breathing, a feeling of exhaustion and palpitations. If you experience these symptoms, you should seek medical attention immediately.


No serious and long-lasting side effects are known to date. The authorities and vaccine manufacturers continue to monitor and collect data on side effects. If you experience serious side effects that are not listed above, you should seek medical attention immediately.




For whom is vaccination not recommended ?

No vaccination is indicated for children under the age of 5 years or aged between 5 and 15 years who do not have any risk factors.

People who should wait before getting vaccinated include:  

  • People who are currently suffering from COVID-19
  • People who have an acute illness (fever, etc.). 



More information

Consult the following websites (French, German or Italian) or 

COVID-19 : Vaccination data and campaign in Geneva

Contact us

Last updated
27 January 2023

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