Flu vaccine - Overview

The flu is a contagious viral infection that spreads every winter. Getting the flu vaccine is the best way to protect yourself against flu.

The best time to get the flu vaccine is before the flu season starts.

It is available from October to the end of April each year.

Who can get a free flu vaccine

Older people and flu vaccine

People aged 65 and older who get flu are at higher risk of serious illness.

Learn about the flu vaccine for people over 65 years

Pregnancy and flu vaccine

The flu vaccine can prevent you from getting flu and passing it on to your baby.

Learn about getting the flu vaccine while pregnant

Children and flu vaccine

Children and young people aged between 2 and 17 years can get the nasal flu vaccine.

Learn about the flu vaccine for children

Healthcare workers and flu vaccine

We recommend that healthcare workers get their flu vaccine to help protect themselves, their patients and the people they work with.

Learn more about flu vaccine for healthcare workers

Types of flu vaccine

This year, there are 2 different types of flu vaccine being offered to different groups:

  • quadrivalent influenza vaccine (QIV)
  • live attenuated influenza vaccine (LAIV)

Quadrivalent influenza vaccine (QIV)

This is recommended for:

  • people aged 65 and over
  • pregnant women
  • people aged 18 to 64 with long-term health conditions
  • healthcare workers

There are 2 brands of QIV vaccine available this year:

  • Quadrivalent Influenza Vaccine (split virion, inactivated) manufactured by Sanofi Pasteur
  • Influvac Tetra manufactured by Mylan

These vaccines can be used interchangeably.

Live attenuated influenza vaccine (LAIV)

This is the nasal spray vaccine for children and young people aged 2 to 17 years.

It is known by the brand name Fluenz Tetra and is manufactured by AstraZeneca AB.

Flu vaccine and egg allergy

If you have an egg allergy, talk to your vaccinator before getting the vaccine. Most people with an egg allergy can get the flu vaccine.

How the flu vaccine works

Getting the flu vaccine is the best way to protect yourself against flu. The vaccine starts to work after about 2 weeks.

The flu vaccine helps your immune system produce antibodies to fight infection. Having the vaccine can stop you from getting sick if you come in contact with the flu virus.

Protection from the flu

Most people who get the vaccine will be protected from the flu. You can still get the flu after vaccination. But you should have milder symptoms and recover faster.

We do not know yet how effective this year's vaccines are. But normally the vaccine reduces the risk of getting flu by 40% to 60%. You need to have the flu vaccine every year. This is because the antibodies that protect you fade over time. Flu strains also change each year.

Flu vaccine and other vaccines

If you have had other vaccines recently, it is safe to get the flu vaccine.

For example, if you have had your:

  • COVID-19 vaccine, booster shot or additional dose
  • pneumococcal vaccine (pneumonia vaccine) - if you are 65 or older this is recommended
  • school vaccines

Children aged 12 to 23 months who are medically at-risk

Wait at least 1 week between the flu vaccine and the pneumococcal vaccine (PCV 13). This reduces the risk of fever-related complications.

Who should not get the flu vaccine

You should not get the flu vaccine if you:

  • have had a severe allergic reaction to a previous flu vaccine or any part of the vaccine (including polysorbate-80)
  • are taking medicines called combination checkpoint inhibitors, for example, ipilimumab plus nivolumab
  • have a temperature greater than 38 degrees Celsius - wait until you are well before getting the vaccine
  • have severe Neutropenia - low levels of a type of white blood cell

If you have primary autoimmune neutropenia, you should be able to get the flu vaccine. Talk to your GP if you are not sure.

Protect yourself from flu

If you do not get the flu vaccine, you need to take extra care to protect yourself.

Protect yourself from flu by:


All HSE immunisation programmes follow the recommendation of the National Immunisation Advisory Committee (NIAC).

Page last reviewed: 3 October 2022
Next review due: 3 October 2025