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What is a vaccine?

Yellow illustrated vaccine vial bottles on a green background
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A vaccine is a type of medicine that train’s the body’s immune system so that it can fight a disease it hasn’t encountered before. Usually given as an injection, vaccines contain a small amount of the virus, toxin or bacteria that they’re designed to protect against. Vaccines help to prevent the spread of infectious diseases, rather than treat a disease once you’ve caught it.

Not only can a vaccine protect you from diseases, it also protects other people in your community. If enough people are vaccinated it can reduce diseases, sometimes getting rid of them completely.

How does a vaccine work?

As we’ve mentioned a vaccine usually contains a small amount of the disease (pathogen) it’s used to protect against. In many vaccines, like flu, the disease is weakened or destroyed as part of the vaccine creation process.

The small amount of the disease in the vaccine allows your immune system to create antibodies. These antibodies work to protect you from the disease if you are infected after you’ve been vaccinated. A vaccination can give you immunity for years, but some need a booster to give you full protection.

There are two main types of vaccines - live and killed vaccines. See the table below for the key differences between these two vaccines.

Live vaccine Killed vaccine
The virus or bacteria has been weakened The virus or bacteria has been destroyed
Not suitable for those with a weakened immune system Can be given to people with a weakened immune system
Offers long-term protection  Several doses or a booster vaccine are needed for full protection

Some of the COVID-19 vaccines are following a new science using RNA rather than giving a live virus. They still help to teach your immune system how to protect you from this virus. You can find out more about the COVID-19 vaccines on the Government website.

What is ‘herd immunity’?

A vaccination also helps protect others in your community, this is known as ‘herd immunity’ or ‘community immunity’. It’s harder for a disease to spread when enough people have been vaccinated. ‘Herd immunity’ helps to protect those who may not be able to have a vaccine, due to illness or a weakened immune system.

Why do we need a COVID-19 vaccine?

A COVID-19 vaccine is needed to help save lives and prevent more people becoming ill. Alongside other treatment, it will also help our lives get back to normal and end the pandemic.

If enough people receive a vaccine it will help to create community immunity which will slow down the spread of COVID-19. Without a vaccine for COVID-19 there will always be a risk of new outbreaks.

Will the COVID-19 vaccine be made compulsory?

While vaccination is our best defence against COVID-19, it’s unlikely it will ever be made mandatory.

There are lots of vaccines we’re all recommended to get as a child, teenager and later on into adulthood. These include vaccines against meningitis, measles, HPV and the flu. The government hasn’t made these vaccines compulsory, but they are a key part of keeping you safe and protected against certain illnesses.

Can I participate in the COVID-19 vaccine trials?

You can take part in COVID-19 vaccine trials and COVID-19 research. If you would like to take part you can sign up to be contacted for coronavirus vaccine studies on the NHS website.

Can I use a numbing cream before vaccinations?

If you’re worried about pain when getting a vaccination or have a fear needles a numbing cream could help. Emla, is a numbing cream that you can apply directly to your skin before needle procedures. It’s available without a prescription online and in your local pharmacy. Just remember to let the healthcare professional know you’ve applied a topical anesthetic to your skin, so they can inject that area.

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