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Covid-19 Vaccine: Debunking harmful myths

What's the truth about the Covid-19 vaccines?

Throughout the pandemic, fake news has exploded online. Myths about coronavirus and vaccines spread fear on social media and have influenced opinions. If someone we trust shares a worrying rumour over WhatsApp, it can be hard to challenge. When combined, it can be hard to tell fact from fiction.

In this article, our Matron Cheryl Lythgoe looks at some of the most common myths about covid-19 vaccines and explains the truth. We also explore how you can talk to your loved ones if they’re hesitant about getting vaccinated.

This article is reviewed and updated regularly by a medical professional. It was last updated on 21st April 2021.

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Covid-19 myths - debunked

Myth 1: “The Covid vaccine was rushed and isn’t safe.”

The truth? The vaccines went through the same rigorous testing as all medications and met the same high standards.

“Rushed” suggests that researchers weren’t following their usual rigorous standards and that corners were cut. That isn’t the case. Rapid development and testing of vaccines isn’t common practice - but that doesn’t mean to say it isn’t safe. Vaccine development is usually slowed thanks to the bureaucracy, funding issues, and waiting for assessment panel dates. Due to the emergency situation, Covid vaccines haven’t been faced with these usual delays. 

The Covid-19 vaccines have had to meet all the expected robust clinical milestones with no safety shortcuts. None of the usual steps were left out in the reported vaccine development. The independent medicines regulator (MHRA) has strict quality, safety, and effectiveness metrics that all medications (including vaccines) must pass. All the vaccines licensed within the UK have passed their strict processes.

These vaccines are new which means it’s impossible to have long-term data at this time. However, these vaccines have been licensed as safe, effective and the best option to prevent illness and death.

Myth 2: “The vaccine affects your DNA.”

The truth? The vaccines don’t interact with your DNA in any way.

The types of vaccine licensed for use against Covid-19 don’t interact with or alter your DNA. The Pfizer-Biotech and Moderna vaccines are based on Messenger RNA or mRNA. mRNA is a small molecule that’s made naturally by your cells, as well as bacteria and viruses. It provides a blueprint for protein manufacture. In vaccine form, they act as chemical negotiators within the body to teach it how to develop an immune response against Covid-19. 

mRNA never enters the nucleus of the cell (which is where our DNA is kept) and therefore doesn’t interact with our DNA in any way. To genetically modify your DNA, you’d need to insert a foreign DNA into the nucleus of a human cell and vaccines can’t do that. 

Myth 3: “The vaccine gives you Covid-19.”

The truth? None of the vaccines contain a live virus, so they can’t infect you.

None of the approved vaccines contain a live virus. Vaccines don’t give you the disease. Instead, they provide your body with the ability to recognise and fight the infection they are designed to protect against. 

The Oxford/AstraZeneca vaccine, for example, uses a harmless virus that has been altered to replicate the Covid-19 virus. This teaches your body how to generate the right immune response.

Myth 4: “The vaccine won’t work against the new strains.” 

The truth? Researchers are continuing to investigate this.

All viruses – including Covid-19 - mutate, that’s how they survive. This is a natural, normal process. When we discuss the ‘variants’, we’re talking about mutated versions of Covid-19.

Vaccine effectiveness is always being assessed. We may find that the efficacy could lessen as more variants emerge over time. Currently, scientists expect the licensed vaccines to protect against the existing known variants. The ongoing research in vaccine development and efficacy will lead the way in how we manage ongoing immunity against existing and new strains.

Early vaccination will cut virus spread and therefore reduce the presence of the original strain and any new variants.   

Myth 5: “The vaccine causes severe side effects.”

The truth? Severe reactions are extremely rare.

If you’ve had a vaccine in the past, you might have experienced some side effects. All vaccines have the potential to cause side effects as they’re engineering an immune response within your body. For most, the vaccine causes mild side effects which feel better within a few days, such as:  

  • Sore arm where the needle went in

  • Feeling tired

  • A headache

  • Feeling achy

  • Feeling sick

If you have a history of allergic reactions, tell healthcare staff before getting the vaccine. Serious allergic reactions are rare. The current data tells us that eleven people in every million (or 0.0011%) will have a moderate to severe reaction.

Staff giving the vaccine are trained to deal with serious reactions. The reactions have been found to occur within fifteen minutes of receiving the vaccine. Because of this, most vaccination sites are asking recipients to wait to monitor any reactions.

Currently the MHRA recommends that anyone with a history of significant allergic reactions shouldn’t have the Pfizer vaccine.

Myth 6: “The Oxford/Astra Zeneca vaccine is dangerous” 

The truth: There is a small risk of developing a blood clot.

Some people are concerned about the risk of blood clots from the Oxford/Astra Zeneca vaccine. There have been a very small number of reports of an extremely rare form of blood clot in the cerebral veins occurring soon after vaccination. This type of blood clot is called sinus vein thrombosis.

They can occur in people who haven’t been vaccinated. 5 per 10,000 of people will get a blood clot with the oral contraceptive pill. The risk of developing a blood clot from a long-haul flight is about 1 per 1,000. 

On the other hand, the risk of getting a blood clot after having the vaccine is just four per million. With that in mind, the risk from the vaccine is comparatively small.

Researchers found that someone who’s been vaccinated is no more likely to have one of these blood clots than the general population.

The Joint Committee on Vaccination and Immunisation (JCVI) has advised that anyone under the age of 40 should be offered an alternative vaccine. This weighs up the risk of being seriously ill with COVID-19 or the extremely small risk of a serious adverse event.

Myth 7: “I’ve been told that the vaccine contains pork/placental cells/eggs/alcohol.”

The truth? The vaccines have been ethically developed so anyone can have them.

There have been many claims around the ingredients of the Covid-19 vaccine - from foetal cells to microchips. Many of these claims are misleading.

The vaccine was originally developed through utilising replicated human kidney cells which are filtered out of the final product.

The claim around microchips refers to an interview with Bill Gates. He said that ‘we will have some digital certificates’. He was talking about the infrastructure for safe, home-based testing – not the vaccine itself.

The vaccines also don’t contain any egg proteins so is safe to give to anyone with egg allergies.

The British Islamic Medical Association urge anyone who’s eligible to have the vaccine. It doesn’t contain pork gelatine and has negligible alcohol. 

Myth 8: “The vaccine can cause issues with fertility.”

The truth? There’s no evidence to suggest this

The Covid-19 virus has spike proteins, which allows the virus to bind with host cells. Antibodies to the spike protein haven’t been linked to infertility after Covid-19 infection. Otherwise, we would have seen a trend of infertility, miscarriage, and stillbirth in people who’ve had Covid-19, but this hasn’t happened.

There’s no evidence to suggest the vaccine affects fertility (especially because the vaccines don’t contain the live virus).

The vaccine trials (as with most medication and vaccine trials) didn’t contain any children or pregnant subjects. However, post-trial data suggests that after you’re vaccinated you can still breastfeed, with no risk to your baby.  

Myth 9: “If I’ve had my Covid-19 vaccine, I don’t need to socially distance or wear a face mask.”

The truth? While the vaccines prevent severe illness, you might still be able to pass on Covid-19

Even when you’ve had your vaccine, it’s crucial to continue to follow the current guidelines. Therefore, the ‘hands, space, face’ advice is still relevant.

The current licensed vaccines have all been effective at preventing severe illness which is what the original end goal was. It’s not yet clear yet how much impact they have on of transferability and immunity. Further research will aim to answer this question. Remember – it’s still important to have the vaccine to prevent severe illness from Covid-19.

Myth 10: “Delaying the second dose means I will lose any protection received in the first dose.”

The truth? Evidence suggests you’ll still have a reasonable level of immunity, and it helps to protect more people.

We don’t yet know how long you’re protected after your first dose. Current research suggests though that it doesn’t drop significantly. Therefore, by delaying the second dose, we enable more people to have a reasonable level of immunity.

The public health decision judged that it’s far preferable to vaccinate twice the number of people than to vaccinate half that amount with only slightly greater protection.

Myth 11: “I don’t need the vaccine if I’ve already had Covid-19.”

The truth? It could be possible for you to catch it again – so it’s important to protect yourself.

It’s not yet clear how strong natural immunity is, or for how long after infection someone has protection against Covid-19. The current evidence appears to suggest that contracting Covid-19 again isn’t common but it could happen, and we still have lots of research to do. It’s still recommended, irrespective of your previous immunity response, to have the vaccine when offered.

How to talk to a vaccine hesitant loved one?

Vaccination is always a hotly debated topic for some, though the majority of the population strongly supporting the national rollout of the Covid-19 vaccine.

If you have a family member, loved one or friend who’s anxious about the vaccine, don’t provide pressure but rather provide support, fact-based information, and the ability to have an open non-judgmental discussion. Even if you don’t understand their thinking, remember that their fears and concerns are real to them. You can share the medical facts by passing on this article.

Unfortunately, we're unable to help members access a COVID-19 vaccine as this is a service being closely monitored and administered through the NHS. Our 24/7 GP Helpline offers advice and support relating to COVID-19, but we're unable to offer any further help with regards to accessing vaccines.

Medically reviewed by Cheryl Lythgoe on 21st April 2021. Keep up-to-date with the latest guidelines on coronavirus at


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