COVID-19: Risks and side effects of vaccination

Vaccines are safe and save lives. The rapid development of COVID-19 vaccines has people asking questions. Here is an overview of the reactions and side effects you can expect.

Vaccines are safe and save lives. The rapid development of COVID-19 vaccines has people asking questions. Here is an overview of the reactions and side effects you can expect.

Millions of people worldwide are hoping for a vaccination against the coronavirus in the near future. Vaccines have been found safe and approved by health authorities in many countries. At the same time, many people are ambivalent because, while they want to protect themselves against infection, they also fear possible side effects from vaccination. They have doubts as to whether the vaccines are actually safe, given the rapid pace of development, and whether possible side effects have been adequately studied. So what vaccine reactions are normal, and what side effects are possible?

Normal vaccination reactions

It is normal to have certain reactions after a vaccination: There may be redness, swelling or pain around the injection site. Fatigue, fever, headache and aching limbs are also not uncommon in the first three days after vaccination.

These normal vaccine reactions are usually mild and subside after a few days. They show that the vaccine is working, because it stimulates the immune system and the body forms antibodies against the infection that is only "feigned" by the vaccination.

Accordingly, such typical vaccination reactions have also been reported after receiving the BioNTech-Pfizer, Moderna, AstraZeneca and the Russian Sputnik V vaccines, which are already in use.

Rarely serious side effects

In addition to the typical vaccination reactions, there were also individual cases of sometimes severe side effects after vaccination, such as allergic shocks, which were reported in detail. But these are isolated cases.

Overall, the approved vaccines are safe, according to the European Medicines Agency ( EMA), the US Food and Drug Administration (FDA) and the World Health Organization (WHO), otherwise they would not have approved the vaccines.

Some of the new vaccines — so-called mRNA vaccines — are different from the established vaccines: they do not contain weakened or killed viruses. Instead they contain only a blueprint for a component of the COVID-19 pathogen.

Others are so-called vector vaccines that use harmless adenoviruses (such as cold viruses that only affect chimpanzees) as transporters to introduce the surface protein of SARS-CoV-2, the spike protein, and thereby trigger the immune response.

Here is an overview of the risks and side effects of the commonly mentioned vaccines:

The Biontech-Pfizer vaccine

During the approval phase, no serious side effects occurred with the BNT162b2 vaccine developed by companies BioNTech of Germany and Pfizer of the US. The typical vaccination reactions such as fatigue and headache were less frequent and weaker in older patients.

However, since this mRNA vaccine has been in use, a few patients had a severe allergic reaction immediately after the injection. One patient in the USA and two Britons even went into anaphylactic shock, associated with reddening of the skin and shortness of breath.

Since these individuals either had no previous illnesses or were not known to be allergic to certain vaccine ingredients, the British Medicines and Healthcare products Regulatory Agency ( MHRA ) warned in particular people who are allergic to certain vaccine ingredients, or have already suffered an anaphylactic shock against getting the vaccination.

The Moderna vaccine

The mRNA-1273 vaccine from US company Moderna is also a gene-based vaccine that is very similar in principle to the one from BioNTech/Pfizer.

During the clinical trials, participants tolerated the vaccine well, according to the manufacturer and testing authorities. The usual vaccination reactions were only mild or moderate and didn't last long. However, almost 10% of those vaccinated with mRNA-1273 experienced fatigue, according to an interim report by an independent surveillance panel.

With the Moderna vaccine, a few patients also had an allergic reaction and a very small number of people experienced facial nerve paralysis. However, it is still unclear whether these reactions are actually related to the core ingredient of the vaccine. It is possible that the side effects were not triggered by the mRNA, but by lipid nanoparticles that serve as carriers for the mRNA and are later broken down by the body.

The AstraZeneca vaccine

At the British-Swedish company AstraZeneca, an incident during clinical trials in September caused a stir because one person suffered inflammation of the spinal cord after vaccination. The trial was briefly halted until an independent panel of experts determined that the inflammation was probably not related to the vaccination.

Otherwise, only typical vaccination reactions such as pain at the injection site, muscle pain, headache and fatigue occurred with the vaccine from AstraZeneca. Again, vaccine reactions were less frequent and milder in older people. This is a vector vaccine. The Russian Sputnik V vaccine

As early as August 2020, the vector vaccine Gam-COVID-Vac (Sputnik V) was approved in Russia, but without waiting for Phase III trials involving tens of thousands of subjects. Sputnik V uses two differently modified adenoviruses (rAd26-S and rAd5S).

There have been considerable reservations worldwide about the vaccine developed by the Gamaleja Research Center in Moscow because the Russian government issued an emergency use authorization after a phase II trial. Furthermore, scientists reviewing the study voiced concern about possible manipulation of the data.

Nevertheless, Sputnik V is already being used not only in Russia but in many other countries, including Belarus, the United Arab Emirates (UAE), India, Brazil and Argentina.

On January 2, Russian Health Minister Mikhail Murashko told journalists that more than 1.5 million doses had been delivered to Russian regions and more than 800,000 people had been vaccinated.

According to the Russian health ministry, only the usual vaccination reactions, such as headaches or fever, have been registered so far. In Argentina, typical vaccination reactions occurred in 317 of a total 32,013 vaccinated people, according to the Argentinian health ministry.

There have been no reports of severe side effects following Sputnik V vaccination. Nevertheless, reservations are apparently high in Russia as well. According to a Reuters report, 52% of 3040 Russian doctors and other health professionals stated in a survey, conducted by

Typical vaccine reactions are mild and disappear after a few days