Re: News has collected some of the concerns around the Covid-19 vaccine. These come from people like you, who follow and comment on our content, our friends and whānau, and our own team members.

We’ve put together stories unpacking them, hopefully easing worries around unknowns, and providing information for conversations in your families and communities. We hope you find it useful.

Here, we look at whether vaccines have long term effects.

No vaccine has ever proven to have long-term negative health impacts.

We have been vaccinating people on a large scale for almost a century against a variety of illnesses. Right now, nearly 80 percent of people under 30 have been vaccinated against tuberculosis, polio, tetanus and measles since birth. 

That is billions of people. None who have proven to experience any long-term health impacts from those vaccinations.

Vaccines can have side effects, but all of these appear either immediately following injection, or within eight weeks of it.

To use the Pfizer Covid-19 vaccination as an example, it is common to experience slight pain or swelling in the area of the injection or, in rare cases, a severe response such as myocarditis, or swelling of the heart. 

In New Zealand, as of October 20, we had administered over 6.3 million doses of the Pfizer vaccine, and had 85 cases of myocarditis. That is 0.001 percent of vaccinations.

You may have also seen reports saying 60 people have died shortly after vaccination in New Zealand. Of these, only one is currently thought to be a direct result of the vaccination, as a result of myocarditis. That is a 0.00002 chance of dying. To put that into perspective, you are 84 times more likely to die of being struck by a meteor from space than dying from getting the Pfzier vaccine. 

What makes up the Pfizer vaccine

The Pfizer vaccine used to fight Covid-19 in New Zealand is also slightly different from older vaccines like the ones for polio and tuberculosis.

All of these past vaccines used a dead version of the virus, alerting your body to the existence of that virus type, and giving it the opportunity to build defenses to fight it off when it encounters the real deal.

The Pfizer vaccine doesn’t have any of the virus in it at all, but instead uses a molecule full of information, called mRNA, to teach your body what to look out for. mRNA works in a more sophisticated way than older vaccines. 

Imagine, for example, there is a hungry tiger set loose in your neighbourhood, but you’ve never seen one before. 

The older vaccines are comparable to learning how to protect yourself by examining a sleeping tiger. You can see what it looks like, how big it is, its claws and teeth, and try and make a plan to protect yourself from it based on that.

The new mRNA vaccines are like being sat down in front of a nature documentary where you can quickly learn everything about tigers and see them in action, before ever actually encountering them in person. 

The goal of mRNA vaccines is not to leave molecules in your body to fight the virus, but to share that knowledge with your cells so they know how to do it.

It also means once your body has learnt the lessons mRNA has to teach, it absorbs everything in the vaccine  - which is essentially some fat and sugars used to carry the mRNA. After a few weeks, all of this would have passed through your system and all that is left of the vaccine is the knowledge within your cells of how to fight Covid-19.

mRNA and Covid vaccines

We’ve actually been studying mRNA vaccines for decades, and have used them in recent years to fight viruses such as the Zika virus, rabies and the flu. Despite being used in multiple trials for large numbers of people over the past decade, no long-term effects related to the vaccine have appeared for the patients.

As of October 20, 6.7 billion doses of Covid-19 vaccines have been administered worldwide - the majority of these have been mRNA vaccines. There have been no reported side effects after eight weeks of receiving a dose.

While there is no evidence that the Pfizer vaccine will have long-term health impacts on you, we know that many people who have contracted Covid-19 are suffering long after they’ve recovered from the virus. 

New research has shown that nearly 40 percent of Covid-19 survivors experience symptoms such as shortness of breath, abdominal issues and depression in three to six months after recovery.

So, if you’re worried about long term effects of the vaccine, remember that all that is left in your body after a few months is knowledge and we have billions of vaccinated people to prove that is the case.

Still have more questions about the vaccine? Check out our series that breaks down popular myths and concerns about Covid-19 and the vaccine.


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