Risks and Side Effects of Coronavirus Vaccines

It is normal that there certain reactions after a vaccine: redness, swelling or pain around the puncture, fatigue, fever, headache and muscle pain. These normal reactions to the vaccine are usually mild and go away after a few days. In addition, they show that the vaccine is working because it stimulates the immune system and the body generates antibodies against the infection "simulated" by the vaccine. Typical reactions have also been recorded with the BioNTech-Pfizer, Moderna, AstraZeneca and Russian Sputnik V vaccines.

Rarely serious side effects

In addition to the typical reactions of vaccination, there were also, in some cases, serious side effects after vaccination, such as allergic reactions, but in isolated cases.

According to the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA), or the World Health Organization, approved vaccines are safe. Otherwise, they would not have allowed its use.

Some of the new vaccines, the so-called mRNA vaccines, differ fundamentally from the established vaccines: they do not contain weakened or killed virus, but are only instructions for a portion of the so-called Spike protein to be produced, thus triggering an immune reaction.

Risks and Side Effects of the Biontech-Pfizer Vaccine

During the approval phase, the active compound BNT162b2 from BioNTech of Germany and Pfizer of the USA, there were no serious side effects. Typical reactions to the vaccine, such as fatigue and headache, were less frequent and weaker in older patients.

However, some patients have shown a strong allergic reaction immediately after injecting the mRNA vaccine. One patient in the US and two in Britain even suffered what is known as anaphylactic shock, combined with reddening of the skin and shortness of breath. Since these people had no previous illnesses and were not known to be allergic, British authorities warned allergy sufferers not to get vaccinated.

Risks and side effects of the Moderna vaccine

The mRNA-1273 vaccine from the American company Moderna is a genetic vaccine that is very similar in principle to that of BioNTech-Pfizer.

During clinical studies, the vaccine was well tolerated by volunteers, based on results from the manufacturer and testing authorities. Therefore, the usual vaccination reactions were only mild or moderate and of short duration. However, according to an interim report from an independent monitoring committee, fatigue occurred in at least 9.7 percent of those vaccinated with mRNA-1273.

With the Moderna vaccine there were also few allergic reactions and some facial nerve palsy. It is not yet clear whether these reactions are actually related to vaccination. It is possible that the side effects were not caused by the mRNA, but by lipid nanoparticles that serve as carriers of the mRNA and are then broken down by the body.


The British-Swedish company AstraZeneca caused some astonishment during clinical trials in September, because a test person suffered an inflammation of the spinal cord after vaccination. The study was briefly interrupted until an independent panel of experts determined that the inflammation was not related to vaccination.

With the AstraZeneca vaccine, too, only typical vaccine reactions occurred, such as injection site pain, muscle pain, headache, or tiredness. Here, too, reactions to the vaccine were less frequent and milder in older subjects. It is a vector vaccine.

Risks and side effects of the Russian Sputnik V vaccine

The adenoviral vector vaccine Gam-COVID-Vac (Sputnik V) was approved in Russia as early as August 2020, but without waiting for phase III studies with tens of thousands of test subjects. Sputnik V uses two differently modified adenoviruses (rAd26-S and rAd5-S).

Around the world there were reservations about the vaccine developed by the Moscow research center Gamaleja, since in the study presented on the vaccine there could have been manipulation.

However, Sputnik V is already being used in many countries, not only in Russia, but also in Belarus, the United Arab Emirates (UAE), as well as in India, Brazil and now also in Argentina.

Him> Mikhail Murashko, told reporters that more than 1.5 million doses had been delivered to Russian regions and that more than 800,000 people had been vaccinated.

According to the Russian Ministry of Health, so far only the usual reactions to vaccines, such as headache or fever, have been recorded. According to the Ministry of Health, 317 of the 32,013 vaccinated people in Argentina also experienced vaccination reactions.

There are no reports of serious side effects after vaccination with Sputnik V. At the same time, vaccine stocks are apparently large in Russia. According to a report by Reuters, 52 percent of 3,040 Russian doctors and other health professionals said in surveys that they did not want to be vaccinated with Sputnik V due to insufficient data.

Should we expose ourselves to the risks of vaccination?

Each person must answer this question for himself. It is an individual matter to weigh the benefits and risks. Is it more important for me to protect myself and others with a vaccine and to return to a more normal life? Or are the risks of these new vaccine technologies too great for me?

It should be noted that nothing is known about the possible long-term effects of individual vaccines. The long-term studies that accompany vaccines around the world, and which will continue after approval, will likely provide further clarity on this matter.

According Christian Bogdan, director of the Institute of Clinical Microbiology, Immunology and Hygiene of the University Hospital of Erlangen, "there is a residual risk" and adds that "it must be verified how high it is in the coming months and years".