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. This flu season, the vaccine protects against 4 strains of flu.

Read about 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.

Read 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.

Read about getting the flu vaccine while pregnant

Children and flu vaccine

If your child is aged between 2 and 17 years, they will be offered the nasal flu vaccine.

Read 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.

Read more about flu vaccine for healthcare workers

Types of flu vaccine

This year, there are 3 different types of flu vaccine being offered to different groups.

Quadrivalent Influenza Vaccine (QIV)

This is recommended for people aged 50 to 64, pregnant women, people aged 18 to 64 with long-term health conditions and healthcare workers. It is known by the brand name Quadrivalent Influenza Vaccine and manufactured by Sanofi Pasteur.

People aged 50 to 64 have been added to the free flu vaccine programme until the end of April 2022.

Adjuvanted Quadrivalent Influenza Vaccine (aQIV)

This is recommended for people 65 and older. It is known by the brand name Fluad Tetra and is manufactured by Seqirus.

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.

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.

Sometimes people who get the flu vaccine will still get the flu. But most people who get the vaccine will be protected from the flu. If you do get flu after taking the vaccine, you should be less sick and recover more quickly than someone who has not had the vaccine.

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.

COVID-19 and the flu vaccine

You should still get the flu vaccine if you have been vaccinated against COVID-19.

Your COVID-19 vaccine will not protect you from flu.

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 (for people aged 12 and over) - including a booster shot or additional dose
  • pneumococcal vaccine (pneumonia vaccine) - if you are 65 or older this is recommended
  • school vaccines

As a precaution, children aged 5 to 11 years should wait at least 2 weeks between getting their COVID-19 vaccine and the flu vaccine.


If the flu vaccine is needed for children aged 12 to 23 months of age who are medically at-risk, it should be separated from pneumococcal vaccine (PCV 13) by at least 1 week.

This is to reduce the risk of fever-related complications if the vaccines are given at the same time in this age group.

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 severe neutropoenia, which is low levels of a type of white blood cell
  • are ill with a temperature greater than 38 degrees Celsius - wait until you are well before getting the vaccine

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: 8 November 2021
Next review due: 8 November 2021