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.

You may have heard people say that the vaccine doesn’t stop you from getting Covid (infection), and it doesn’t stop you from spreading it to others (transmission).

Ultimately, what they’re saying is: How effective is the vaccine, really? 

The short answer is: The vaccine doesn’t give perfect protection, but it’s way better than nothing.

It reduces infection and transmission, and is also very effective in reducing severe illness, hospitalisation and death – which is just as important.

1. How effective is the vaccine in preventing you from getting Covid?

The vaccine is not a protective barrier that will 100 percent guarantee you won’t get Covid. However, it greatly reduces your chances of getting it.

Pfizer, the vaccine we’re using in Aotearoa, has an efficacy rate of 95 percent. This does not mean that 95 out of 100 people vaccinated won’t get Covid, and that 5 out of 100 people will.

What it means is that during clinical trials, researchers found that after two doses of the vaccine, people were 95 percent less likely to get Covid each time they were exposed to the virus compared to unvaccinated people.

These clinical trials were conducted mainly with an earlier strain, before the spread of Delta. Research has found that the Pfizer vaccine may be 88 percent effective against the Delta strain. This means after two doses of the vaccine, you are 88 percent less likely to get Delta compared to someone completely unvaccinated.

It’s also good to note that cases where people get Covid after being vaccinated are known as “breakthrough infections”.

2. How effective is the vaccine in preventing you from spreading Covid to others?

By preventing people from getting infected, the vaccine greatly reduces the spread of Covid. If you are 88 percent less likely to get the virus after being fully vaccinated, you are also going to be less likely to spread the virus to other people.

There is uncertainty, however, in how effective the vaccine is in reducing transmission if you do end up getting it after being vaccinated. 

The current evidence shows the vaccine is at least a little effective in preventing infected people from passing on the virus, but this protection diminishes a few months after your second shot.

Dr Janine Paynter, Senior Researcher at the Faculty of Medical and Health Sciences, University of Auckland, suggests that “​​We’ll need a booster eventually to maintain effectiveness at preventing transmission.

A recent study has also found that vaccinated people who got Covid could carry similar levels of the virus as unvaccinated people.

However, the vaccine is effective in reducing symptoms and speeding up recovery. 

Reducing symptoms such as coughing, and reducing the amount of time you’re ill, can in turn reduce transmission as there’s less chance for you to spread the virus through the air.

It’s also important to think of the vaccine as part of a wider toolkit against Covid. While we know it helps increase protection significantly, it still isn’t 100 percent effective and needs to be used alongside safety measures like masks and limits on indoor gatherings - even if you’re fully vaccinated.

3. The vaccine is very effective at preventing severe illness, hospitalisation and death.

While a lot of focus has been put on how effective the vaccine is in reducing infection and transmission, it has another function that is just as important.

The vaccine is extremely effective at preventing severe illness, hospitalisation and death.

In Italy, almost 99 percent of Covid deaths since February were not fully vaccinated.

A recent study of 22 million people in France also found vaccination reduces the risk of death or hospitalisation by 90 percent.

It’s a similar story in Aotearoa. On October 12, Director-General of Health Dr Ashley Bloomfield said of the 158 people hospitalised since the start of the outbreak, only three were fully vaccinated with sufficient time (14 days after the second dose to develop full immunity). 

So yes, there are going to be some breakthrough cases. And yes, some of these breakthrough cases will spread the infection onto others.

But the vaccine greatly reduces the number of these cases, and greatly reduces the risk of severe disease and death. In other words, the vaccine saves lives.

You can book your vaccine (or choose a walk-in site) at bookmyvaccine.nz.

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

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