Covid vaccine safety and the side effects
If you or someone you know is hesitant about getting a Covid jab, or worried about any part of the process, read our round-up to get the facts about vaccination...
How vaccines work
Vaccines train your body to fight disease by introducing a modified version which trains our immune system to attack and inactivate the real thing. Most vaccines do this by using a weakened, harmless form of the virus that our immune cells can learn how to defeat. Others introduce a specific part of the virus that’s particularly important for our systems to recognise to do the same thing. Some Covid vaccines use a newer approach, which uses mRNA (messenger RNA) instead. This is a set of instructions, akin to those our body makes on its own, which teaches our cells how to make the key piece of the virus themselves. This triggers an immune response that shows our system how to defeat the virus.
The adenovirus Covid vaccines
The Oxford/AstraZeneca vaccine is an adenovirus vaccine, a type that has been well-studied in previous clinical trials. It uses a harmless modified virus to deliver the genetic code of the spike protein to the body. None of the vaccines have the ability to alter your DNA (a concern that has been doing the rounds). The vaccine also cannot replicate inside your body and only stays there for a few days.
Could vaccination make Covid worse?
This is another concern that did the rounds on social media. One of the things that vaccine developers look out for during the research stages is something called ADE – antibody-dependent enhancement. This is where an initial infection – or vaccine – produces antibodies that don’t protect you from a virus, and instead actually bind to them, making a second or post-vaccine infection more severe. It’s something researchers are aware of and check for when developing vaccines. In clinical trials for the approved Covid vaccines, there wasn’t any evidence of ADE.
Is the vaccination programme making a difference?
The Covid vaccines being deployed in the UK are already having a positive effect – reducing the risk of serious illness and bringing down the number of hospitalisations. Data from a real world study by Public Health England show that since January, protection against symptomatic Covid, four weeks after the first dose, ranged between 57% and 61% for one dose of Pfizer/BioNtech and between 60% and 73% for the Oxford/AstraZeneca vaccine.
The mRNA Covid vaccines
The Pfizer/BioNTech and Moderna vaccines use mRNA (messenger ribonucleic acid). This contains the code for cells to create a part of the coronavirus – the ‘spike’ protein that our immune systems need to recognise and fight. It’s true that the use of mRNA vaccines is new, but the technology hasn’t popped up overnight. The World Health Organisation (WHO) points out that mRNA vaccines have been studied for more than a decade. The technology is also being studied for a wide range of potential therapeutic uses, including in the fight against cancer.
What else is in the Covid vaccines?
Another common concern is that vaccines contain harmful ingredients, or ones which don’t line up with people’s values or beliefs. None of the Covid vaccines contain any animal products, and all of the vaccines being offered in the UK are Halal and Kosher. Aside from the active ingredient, the main ingredient in vaccines is usually water. Other ingredients are found in tiny amounts and usually for stability purposes to ensure maximum efficacy. The vaccines are not made from human embryos, as some social media reports have claimed. The Vaccine Knowledge Project explains that the Oxford/AstraZeneca vaccine uses a harmless virus that was grown in human embryonic stem cells, which are copies of stem cells that originally date from the 1970s and would otherwise have been destroyed.
Covid-19 vaccine side effects
The data from clinical trials show that the risk of severe side effects from the Covid vaccines is tiny, and real world data we have so far from millions of first doses given in the UK reflects this. This doesn’t mean you won’t get side effects. In fact, experiencing some temporary side effects after vaccination is pretty common, but they aren’t serious. The MHRA, which is in charge of monitoring vaccine data in the UK, says the most common side effects seen so far from both vaccines available are: Sore arm, Flu-like symptoms – headache, chills, fatigue (tiredness), nausea (feeling sick), fever, dizziness, weakness, aching muscles, and rapid heartbeat. While described as ‘mild’, these symptoms can nevertheless be unpleasant. They can be treated with normal painkillers, rest and fluids, and should be gone within a few days.
More serious adverse reactions
The risk of severe effects from the vaccine is tiny when compared with the risk of getting ill from Covid-19. It’s also important to realise that vaccine safety monitoring picks up any serious illness somebody might experience after having a vaccine, but this doesn’t mean the vaccine caused it.