Updated 16th January 2023

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Are sharks being killed for COVID vaccines? Does the vaccine contain monkey cells? And will it alter your genes? We tackle the most common COVID-19 vaccine myths

Written byZOE Editorial Staff

We’ve taken a closer look at some of the common myths and misinformation about COVID vaccines, so you can get the facts straight before you decide whether or not to have a jab.

MYTH: COVID-19 vaccines contain coronavirus

Although some COVID-19 vaccines in development use harmless, killed versions of the SARS-CoV-2 coronavirus to induce immunity, such as the Chinese Sinovac jab, this is not the case for either of the COVID-19 vaccines currently available in the UK. 

Both the Pfizer and Oxford/AstraZeneca vaccines contain short pieces of genetic code that instructs your cells to make a small section of the virus called the spike protein. Your immune system then responds to the spike protein, so you will recognise it if you encounter the real virus. 

These vaccines do not contain any actual COVID-19 virus, and your cells can’t produce the whole virus from the genetic code they receive. 

MYTH: COVID-19 vaccines alter your genes

The Pfizer vaccine contains a form of genetic code known as mRNA (messenger ribonucleic acid) that instructs your cells to make the virus spike protein.

However, mRNA differs from the DNA that encodes your genes, and your cells cannot turn mRNA into DNA or integrate it into your genes.

What’s more, mRNA is very fragile. It’s broken down by your cells within 72 hours and doesn’t reach the nucleus (the part of your cells where your DNA is stored).

The AstraZeneca vaccine is made from a harmless virus which carries a small piece of DNA encoding the instructions to make the coronavirus spike protein.

These types of viruses do not alter the DNA of cells, and the vaccine DNA has been engineered so that it can’t multiply (replicate) or integrate into your genes.

MYTH: COVID-19 vaccines aren’t vegan, halal, or kosher

The UK COVID vaccines do not contain any ingredients of animal origin, although lab-grown human cells are used at one point in the production of the Oxford/AstraZeneca vaccine (see later). 

The British Islamic Medical Association has released position statements confirming that the vaccines are halal and advised Muslims to accept either the Pfizer or Oxford AstraZeneca vaccines. 

The Hindu Council UK and Board of Deputies of British Jews have also supported the vaccine rollout. 

MYTH: Thousands of sharks are being killed for COVID-19 vaccines 

Millions of sharks are hunted each year globally and squalene, a naturally occurring oily substance, is often harvested from their livers. 

90% of the squalene harvested from sharks is used in the cosmetics industry. Some of the remainder is used in certain types of vaccines as an adjuvant, which helps to boost the immune response. This is particularly useful in some vaccines designed for children or the elderly.

However, neither of the COVID-19 vaccines currently in use in the UK contain shark squalene or any other ingredients derived from animals. The full list of ingredients for the Pfizer and Oxford/ AstraZeneca vaccines are available online.

MYTH: COVID-19 vaccines contain cells from aborted fetuses and/or monkeys

The Oxford/AstraZeneca vaccine is based on a harmless, modified version of a cold virus normally found in chimpanzees, known as adenovirus. The virus has been genetically changed so that it is impossible for it to cause disease in humans, and it has been used safely in many thousands of people.

In order to produce the vaccine, large quantities of viruses have to be grown in living cells. In the case of the Oxford/AstraZeneca vaccine, the viruses are grown in HEK293 cells - a so-called ‘immortalised cell line’ that was originally derived from a small sample of cells from the kidney of an aborted fetus in the 1970s and has been grown in the lab for decades. The viruses are then highly purified to ensure that the final vaccine does not contain any of these cells.

The Pfizer vaccine does not use any human or animal cells in manufacturing, so there is no chance that there will be any cells in the final vaccine. However, the research team did use similar long-established lab-grown fetal cell lines in the earlier stages of vaccine development to confirm the vaccine was effective.

Neither vaccine uses cells derived from monkeys during production, though monkey cell lines are used to grow other viruses for vaccines in use in the UK.

MYTH: COVID-19 vaccines will make you infertile

This myth seems to have originated from a German doctor who asked the European Medicines Agency to delay the COVID-19 vaccines because the COVID spike protein shares some similarities with the code for a protein called syncytin-1, which is found in the placenta. 

The doctor theorised that antibodies to the COVID spike protein induced by the vaccine might also attack placental tissue, making women infertile. 

However, the commonalities in the code for the COVID spike protein and syncytin-1 are very small and aren’t enough to trigger this kind of immune cross-reaction. The Royal College of Obstetricians and Gynaecologists has issued a statement saying that there is no evidence or biological mechanism linking the vaccines to infertility. 

MYTH: One of the first participants in a COVID-19 vaccine trial died

Rumours circulating on social media have suggested that one of the first people to receive a COVID-19 vaccine in a trial, Dr Elisa Granato, died. However, she has since appeared on BBC News, confirming that she is alive and well. 

Although deaths did occur during the vaccine trials, there were more deaths in the placebo groups than the vaccine groups for both the Oxford/AstraZeneca and Pfizer vaccines. There were no deaths linked directly to the vaccine, and the deaths occurred at a similar rate as expected in the general population. 

MYTH: If you’ve had COVID-19, you don’t need to get the vaccine

If you’ve had COVID-19, you may have some immunity to the virus. However, experts aren’t sure how robust this immunity is or how long it lasts, and there have been several reports of re-infection.

COVID-19 vaccines provoke a more predictable and reliable immune response than a natural infection, which experts think may provide longer-lasting immunity. So even if you’ve had COVID-19, it is still important for you to get the jab. 

The clinical trials included people who had previously had COVID-19, so we know the vaccine is safe if you’ve had the virus (although you may be more likely to feel after effects).

Some studies have suggested that getting one dose of vaccine may provide sufficient protection if you have previously had the virus, and this is now the recommended practice in France. However, the NHS is currently continuing with two doses to ensure complete protection for the population.

MYTH: The vaccines cause Bell’s palsy

Bell’s palsy is a temporary weakness or paralysis in the muscles of the face. It’s not clear what causes it, but it may be due to infection.

During the Pfizer vaccine trial, a small number of people (approximately 0.01%) developed Bell’s palsy. This is in line with the number of people you would expect to develop the condition in the general population during this time, and the events were not considered to be related to the vaccine. 

The yellow card system continuously monitors the safety and potential after effects of the vaccine used in the UK, to keep watch for any rare events like this.

MYTH: I can stop wearing a mask when I’ve had my COVID-19 vaccine

You need to continue protecting yourself and others after you have received your jab because immunity is not instant. It takes at least two weeks for some level of protection to build after the first dose. And it may be possible for you to catch the virus and pass it on to others after being vaccinated, even if you don’t become ill.

What’s more, no vaccine provides 100% protection, so while rates of COVID-19 are still high, you may still be at risk from the disease despite being vaccinated. 

MYTH: You can’t have a COVID-19 jab if you’ve got allergies

The COVID vaccines do not contain any common allergens like eggs, shellfish, or penicillin. However, a small number of people have had an allergic reaction to the Pfizer vaccine (11 cases per million doses).

As a result, people with a history of severe allergies resulting in anaphylaxis should talk to their doctor or vaccination team before getting a jab. 

You may be advised to have the Oxford AstraZeneca vaccine instead of the Pfizer vaccine, and/or you may be vaccinated in a special facility that can look after you should you suffer a reaction. 

FACT: Getting a COVID-19 jab will protect you and others

We know that the current COVID vaccines are safe and effective, and they are already having an impact on the number of cases across the UK. Getting vaccinated not only protects you from COVID-19 but it also protects those around you, including the most vulnerable in our communities such as people with serious health conditions like cancer or autoimmune diseases.

We need to gather as much data as we can about the impact and any after effects of COVID-19 vaccines to support the rollout and help end the pandemic. 

If you’re not already using it, download the ZOE COVID Study app and use it to record your COVID-19 vaccine, followed by daily health reports to help us monitor the after effects and impact of vaccination.

You can also register a profile and log reports on behalf of elderly relatives who may not be able to use the app themselves. 

This will be the largest independent community-led COVID vaccine study in the world, providing vital information to ensure public safety and help end the pandemic.

Stay safe and keep logging.

Find out more:

COVID-19 vaccine myths debunked - Mayo Clinic

Five Covid-19 vaccine false theories - debunked - BBC Bitesize

'Mandatory, unsafe and not halal': Covid-19 vaccine myths debunked - ITV News

Vaccines - FullFact