If you are concerned over the risk of the COVID-19 vaccine, read this first!

Industry Insights


For those of you who may be concerned or hesitant about receiving the COVID-19 vaccine, here’s what has helped our decision-making at Sprout.

The only vaccinations to be approved for COVID-19 at the time of writing use the mRNA (messenger ribonucleic acid) method. We looked at the science on the development of these vaccines in order to examine whether some commons concerns were founded.

Concern: mRNA vaccines are new and have not been studied before

It’s true that the COVID-19 vaccines are the first approved vaccines based on mRNA technology, but they have been developed and studied in other diseases such as cancer.1

Human studies of mRNA vaccines have been taking place for many years.1

Concern: I’ll get severe side effects

It’s true that you might get side effects, but the evidence strongly suggests that these are likely to be mild, and only last a short time, i.e. a little soreness at the injection site and typical effects associated with receiving other vaccines, including the influenza vaccine.

To date, the BioNTech and Pfizer vaccine has been studied in a placebo-controlled trial of 43,548 participants. Only short-term, mild side-effects, similar to side effects from the flu vaccine, were common. The most frequent side effects were pain, redness and swelling at the injection site, followed by short-term headache, fatigue and muscle pain2.

Serious adverse effects were uncommon and similar low numbers of participants experienced severe events in the vaccine and placebo groups2.

No-one in the study died due to the vaccination2.

Concern: I might get COVID-19 from the vaccination

The mRNA COVID-19 vaccines do not use the live virus that causes COVID-19. Therefore, mRNA COVID-19 vaccines cannot give you an infection3. However, as it typically takes a few weeks for the body to build immunity after vaccination, it is still crucial to avoid infection by maintaining other COVID-19-related safety measures such as wearing a mask and social distancing4.

Concern: No-one knows the long-term effects

It’s true that no-one knows the long-term effects of the COVID-19 vaccines, but from what we know about mRNA vaccines so far, the risk of long-term unwanted effects is low.

The data from the BioNTech and Pfizer vaccine trial are based on an average of 2 months follow-up after participants received the second injection. However, the risk of long-term effects is considered to be low because:

1.  mRNA does not enter the cell’s nucleus, therefore scientists believe it is unlikely that it would enter human DNA3

2.  the body quickly breaks down mRNA3

For a full list of facts and frequently asked questions about the COVID-19 vaccines, please check out the Centers for Disease Control and Prevention (CDC) Vaccines Information site: Click here.

Get the science in lay terms

We love hearing scientists put the data into lay terms. Here are some social media streams we have found informative and engaging:

Laurel Bristow, MSc – Clinical Research Coordinator at Emory University in the US: Click here.

Jessica Malaty Rivera, MS – Infectious Disease Epidemiologist and Science Communication Lead for the @covidtrackingproject: Click here.

Team Halo – in partnership with University of London’s school of Hygiene and Tropic Medicine, and in collaboration with the UN Verified Initiative: Click here.


1.  Pardi N, Hogan MJ et al. mRNA vaccines – a new era in vaccinology. Nature Reviews, Drug Discovery. 2018; 17, 261-279

2.  Polack FP, Thomas SJ, Kitchin N, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med.

3.  Abbasi J. COVID-19 and mRNA Vaccines-First Large Test for a New Approach. 2020;324(12):1125-1127.

4.  Centers for Disease Control and Prevention. Facts about COVID-19 Vaccines. Click here.. Accessed 17 December 2020.