COVID-19 vaccines

Vaccines are the safest way to prevent infectious diseases. They teach your immune system (your body's natural defences) how to protect you from a specific virus.

Booster doses are recommended to extend the protection of COVID-19 vaccines.

Bivalent (adapted) vaccines

The European Medicines Agency (EMA) and National Immunisation Advisory Committee (NIAC) have recommended adapted mRNA COVID-19 vaccines as booster doses.

These adapted vaccines work in the same way as the original Pfizer and Moderna COVID-19 vaccines.

While all previous vaccines offer protection against COVID-19, the adapted vaccines are expected to give wider protection against COVID-19 variants. This includes the Omicron variant.

Doses and immunity

The doses needed for all COVID-19 vaccines that have been used in Ireland are listed below.

What does ‘first round of COVID-19 vaccination’ mean?

When we say ‘first round of COVID-19 vaccination’ we mean your dose 1 and dose 2 if you got AstraZeneca, Moderna or Pfizer. Or your single dose if you got the Janssen vaccine.

If you have a weak immune system, you should have been offered an ‘additional dose’ to give you better protection. This is because your immune system may not respond as well to vaccination. You will still need your booster doses after this additional dose.

Pfizer/BioNTech COVID-19 vaccine

For your first round of vaccination, you will need 2 doses of the Pfizer/BioNTech vaccine. You should get your second dose 21 to 28 days after your first dose.

It takes 7 days after the second dose for the Pfizer/BioNTech COVID-19 vaccine to work.

If you recently had COVID-19, wait at least 4 weeks before getting your dose 1 or dose 2.

Booster

After this, booster doses are recommended to extend vaccine protection.

Adapted Pfizer/BioNTech COVID-19 vaccines are now being offered as booster doses. These vaccines are expected to give you better protection against COVID-19, including the Omicron variant.

Find out who is being offered a booster dose now

Moderna/Spikevax COVID-19 vaccine

You will need 2 doses of the Moderna COVID-19 vaccine. You should get your second dose at least 4 weeks (28 days) after your first dose.

It takes 14 days after getting the second dose for it to work.

If you recently had COVID-19, wait at least 4 weeks before getting your dose 1 or dose 2.

Booster

After this, booster doses are recommended to extend vaccine protection.

Adapted Moderna COVID-19 vaccines are now being offered as booster doses to people aged 30 and older. These vaccines are expected to give you better protection against COVID-19, including the Omicron variant.

Find out who is being offered a booster dose now

Novavax COVID-19 vaccine (Non-mRNA)

The Novavax COVID-19 vaccine is called Nuvaxovid.

We do not know yet how long immunity will last after getting this vaccine. Clinical trials are happening now to find this out.

How to get the Novavax vaccine

mRNA vaccines (Pfizer or Moderna) are the recommended vaccines for your first round of COVID-19 vaccination.

But some people may not be able to get an mRNA vaccine or have chosen not to get one. For example, because of an allergy to one of the vaccine's ingredients. In these cases, you may be offered the Novavax vaccine.

Phone HSELive on 1800 700 700 to arrange getting the Novavax vaccine at a vaccination centre.

Doses needed

The number of doses you need will depend on if you have been vaccinated against COVID-19 yet.

Not vaccinated

If you have never had a COVID-19 vaccine, you will need 2 doses of the Novavax vaccine, 21 days apart.

Not completed your first round of vaccination

This means you only had the first dose of either the Pfizer, Moderna or AstraZeneca vaccine.

You can get the Novavax vaccine as your second dose, 28 days after your first COVID-19 vaccine dose.

Booster

If you had your first round of vaccination with Pfizer, Moderna or AstraZeneca, you may be offered the Novavax vaccine as a booster dose if you are 12 or older. This may be offered in cases where you cannot get or have chosen not to get an mRNA vaccine as your booster dose.

Getting different COVID-19 vaccines

If you had the Novavax vaccine as your first round of COVID-19 vaccination, further doses of Novavax may be considered as boosters after a risk-benefit discussion with your vaccinator.

Additional dose

People with a weak immune system are offered an additional dose for better protection. mRNA vaccines (Pfizer or Moderna) are the recommended vaccines for an additional dose.

In cases where you cannot get or choose not to get an mRNA vaccine, you may be offered the Novavax vaccine as your additional dose if you are 12 or older.

This will only be offered if you did not have 2 doses of the Novavax vaccine as your first round of vaccination. At this time, no additional dose is recommended if have a weak immune system and you had the Novavax vaccine as your first round of COVID-19 vaccination.

Read more about getting an additional dose

Janssen/Jcovden COVID-19 vaccine

The official name of the Janssen COVID-19 vaccine is 'Jcovden'.

You may be offered the Janssen vaccine if the Moderna vaccine or the Pfizer vaccine is not recommended for you. For example, if you had an allergic reaction to either of these vaccines.

First round of COVID-19 vaccination

You will need 1 dose of the Janssen COVID-19 vaccine for your first round of COVID-19 vaccination.

It takes 14 days for the vaccine to work.

If you recently had COVID-19, wait at least 4 weeks before getting your first dose.

Booster

After this, booster doses are recommended to extend vaccine protection.

Find out who is being offered a booster dose now

You will be offered a single booster dose of either the Moderna vaccine or the Pfizer vaccine if these vaccines are suitable for you.

AstraZeneca COVID-19 vaccine (not currently available)

The official name of AstraZeneca's COVID-19 vaccine is 'Vaxzevria'.

This vaccine is not available in Ireland at this time.

If you did not get your second dose

If you had 1 dose of the AstraZeneca vaccine, you will be offered the Pfizer/BioNTech vaccine or Moderna COVID-19 vaccine for your second dose. This will mean that you have completed your first round of COVID-19 vaccination.

The Moderna COVID-19 vaccine is only used in adults aged 30 and older in Ireland.

You should get your second dose at least 28 days after getting your first dose of AstraZeneca. Bring your vaccination card that shows you have had 1 dose of the AstraZeneca vaccine.

If you recently had COVID-19, wait at least 4 weeks before getting your second dose.

Find a walk-in vaccination clinic or book a COVID-19 vaccine appointment.

Booster

After this, booster doses are recommended to extend vaccine protection.

Find out who is being offered a booster dose now

If you got the AstraZeneca vaccine before, you will be offered a single booster dose of either the Moderna vaccine or the Pfizer/BioNTech vaccine.

Getting different vaccines

You may be offered a different vaccine for your second dose or booster dose to the one you originally had. For example, you may get a booster dose of the Pfizer vaccine after getting the AstraZeneca vaccine for your first 2 doses.

So far, there have been no concerns about serious side effects with this option. Some side effects may be more common if you get a different vaccine from the one you got previously. For example, pain, fever, headache and fatigue. These side effects do not last long.

Studies have found that the immune response after getting different vaccines may be as good as getting the same vaccine. In some cases, it can be better.

People can choose this option because it has been advised by the National Immunisation Advisory Committee (NIAC ) in Ireland. It is not yet approved by the European Medicines Agency (EMA). At the moment, the EMA has only approved the use of 2 doses of the same vaccine for your first round of vaccination.

Vaccine types

The different types of COVID-19 vaccines used in Ireland are:

  • mRNA - Pfizer/BioNTech and Moderna
  • viral vector - AstraZeneca and Janssen
  • protein subunit - Novavax

Read about the different vaccine types - mRNA, protein subunit and how they work

Side effects and safety

Like all medicines, COVID-19 vaccines can cause side effects. Most of these are mild to moderate and do not last long.

Read about COVID-19 vaccine side effects and safety

Protection from COVID-19

Anyone who gets COVID-19 can become seriously ill or have complications. Getting vaccinated is the best way to protect yourself and others.

You can still get COVID-19 after vaccination. But being vaccinated can reduce how serious your symptoms will be.

Continue to follow public health advice on how to stop the spread of COVID-19. For example, wearing a face mask and washing your hands properly and often.

How you can protect yourself from COVID-19


This content was fact checked by vaccine experts working in Ireland.