Meyer Clinic

Q&A: What you need to know about the Covid-19 vaccination

The world is the midst of one of the greatest health crises in generations. More than 97,000 people in the UK and more than 2.1 million people worldwide have lost their lives to COVID-19.  After more than a year battling Covid-19, we now have a vaccination that will hopefully put an end to the pandemic.  

COVID-19 vaccines from Pfizer-BioNTech and Moderna have received emergency use authorisation by the Food and Drug Administration (FDA) while Oxford-AstraZeneca has been approved by the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK.  

Getting the COVID-19 vaccine can help protect you and those around you from getting COVID-19. But can you trust that it’s safe? How effective is it? Are there any side effects? 

Meyer Clinic Medical Director Dr Annelize Meyer answer these questions so you can make an informed decision. 

How does the COVID-19 vaccine work?
Vaccines work with your immune system so your body will be ready to fight the virus if you are exposed. The COVID-19 vaccine helps your body develop proteins called antibodies that make you less susceptible to the disease.  

The Pfizer-BioNtech and Moderna mRNA 1273 are synthetic vaccines. They encode the spike protein, the button on the surface of the SARS-CoV2 virus. It is not a live virus, cannot replicate itself and is quickly destroyed in the cell shortly after translation. Once the spike protein is translated, an immune response is elicited, resulting in production of antibodies against the spike protein. When the SARS-CoV2 spike protein is bound up by antibodies, it cannot attach to and infect human cells.  

Oxford-Astra-Zeneca – called ChAdOx1 nCoV-19 – is a live vaccine that uses a harmless weakened version of a virus that causes the common cold in chimpanzees. Researchers have already used this technology to produce vaccines against a number of pathogens including flu, Zika and Middle East respiratory syndrome (Mers). The virus is genetically modified, so it is impossible for it to grow in humans. Scientists have transferred the genetic instructions for coronavirus’s specific “spike protein” – which it needs to invade cells – to the vaccine. When the vaccine enters cells inside the body, it uses this genetic code to produce the surface spike protein of the coronavirus. This induces an immune response, priming the immune system to attack coronavirus if it infects the body. 

Is the vaccine safe?
COVID-19 vaccines meet rigorous scientific standards for safety before being authorised. All three vaccines have been studied in tens of thousands of people to ensure they meet safety standards. The FDA and MHRA will continue to monitor the safety and effectiveness of authorised vaccines through ongoing clinical trials and vaccination data. 

The vaccine is so new, how can I be sure about its safety?
While COVID-19 vaccines are being developed more quickly than we typically see, scientists are relying on a decade of research to help speed up the process without a need to cut corners. The vaccines are being tested in large clinical trials to make sure they meet safety standards. Before they are approved they need to meet the rigorous standards for safety, effectiveness and quality set by the FDA and MHRA. 

How effective is the vaccine?
The Pfizer and Oxford vaccine stats show they can offer 90% protection; Moderna vaccine was found to have a 94-95% efficacy to prevent COVID-19 symptomatic infection. Accumulating data show virtual complete protection against severe infection (hospitalisation, need for a ventilator or death). Ongoing studies will tell us the durability of this protection. It is not known how well the vaccines protect against asymptomatic infection and transmission. 

Will the vaccine give me the virus?
No. The Pfizer and Moderna vaccines contain a portion of mRNA, but not live virus. After the spike protein is produced, the mRNA is degraded. A normal immune response can lead to low grade fever or achiness, but this is not harmful. The full benefit of immunity won’t occur until a couple weeks after your second dose (booster dose). The Oxford vaccine uses a harmless, weakened version of a common virus which causes a cold in chimpanzees. The virus is genetically modified, so it is impossible for it to grow in humans. Again, the full benefit of immunity won’t occur until a couple weeks after your booster dose. 

What about antibodies and T-cells?
The Pfizer, Oxford and Moderna vaccines have been shown to provoke both an antibody and T-cell response. Antibodies are proteins that bind to the body’s foreign invaders and tell the immune system it needs to take action. T-cells are a type of white blood cell which hunt down infected cells in the body and destroy them. Nearly all effective vaccines induce both responses. Data indicates the Oxford vaccine induces robust antibody and T-cell responses across people of all ages.  

Will the vaccine cause side effects?
As with other vaccines, it is normal to experience some pain, redness or swelling at the injection site, fatigue, headache, muscle aches, or low-grade fever following the vaccination, which should go away on their own in a day or two. This reaction does not mean that the vaccine has given you COVID-19. These symptoms are typical reactions to most vaccines and are a sign that your immune system is doing exactly what it is supposed to do – building up protection to the disease. 

Could the COVID-19 vaccine cause an allergic reaction?
Allergic reactions to vaccines, in general, are rare. Some people have reported severe allergic reactions to the Pfizer vaccine, but these appear to be rare. If you have experienced severe allergic reactions to vaccines or injectable drugs in the past you should discuss the risks with your GP before going ahead with the vaccine.   

If I get the COVID-19 vaccine, will I test positive for the virus?
No. Positive tests for viral proteins (antigen tests) or nucleic acid (PCR tests) are due to COVID-19, not vaccine. A positive antibody test can be from infection or immunisation. 

Do I still need the vaccine if I’m not high risk?
COVID-19 can be severe in any age groupThe protection you get from the vaccine is not just for yourself but for others who are susceptible around you. Getting vaccinated is doing your part in getting to a goal of herd immunity. The more individuals who are immunised, the less effectively the virus can transmit. 

Can’t I just let other people get the vaccine?
We know that vaccines save lives and can help us turn the page on the coronavirus. Vaccines have eradicated smallpox, nearly eliminated measles and polio, and minimised the impact of countless other diseases. To achieve a similar result from the COVID-19 vaccine requires a certain percentage of people to get vaccinated in order to achieve herd immunity. We all need to work together to protect ourselves, our loved ones and our community, and the COVID-19 vaccine is the most effective way to keep all of us safe. 

Do I need the vaccine if I already had COVID-19 and recovered?
Immunity does develop after COVID-19 infection however it wanes in the months following infection. Vaccine may be helpful to prevent re-infection if it has been more than 3 months since you tested positive. 

Should I get the vaccine if I had a positive antibody test for COVID-19?
It is not recommended to use antibody testing to make decisions about immunisations. A positive antibody test is evidence, but not proof, of past infection. A positive antibody test is not a guarantee of immunity.   

How can I protect myself until I get the vaccine?
The best defence against COVID-19 is to continue following safety precautions. Cover your mouth and nose with a face mask when around others, avoid close contact with people who are sick, stay at least 2 metres away from people outside of your household, avoid crowds and wash your hands often and thoroughly. Alongside this, it is important to work on building up your immune system. There are simple ways we can do this. I advise my patients to take a Vitamin D supplement which helps boost the immune system; take moderate exercise; stay hydrated; limit sugar intake; and to eat more whole plant foods like fruits, vegetables, nuts, seeds, and legumes which are rich in nutrients and antioxidants that may give an upper hand against harmful pathogens. 


If you have any concerns about your health or mental wellbeing or feel you may benefit from a bespoke one-to-one session with a healthcare professional, book in for an online or in-clinic consultation with Dr Meyer. Call 01243 771455 or email info@www.meyerclinic.co.uk for more details.

Exit mobile version