Flu vaccine FAQ’s
Frequently Asked Questions about the Flu Vaccine:
Influenza is a highly infectious acute respiratory illness caused by the influenza virus. Influenza affects people of all ages. Outbreaks of influenza occur almost every year, usually in winter. This is why it is also known as seasonal flu
Flu is often self limiting with most people recovering in 2-7 days. However, flu can be severe and can cause serious illness and death, especially in the very young and in the elderly. Serious respiratory complications can develop, including pneumonia and bronchitis, to which older people and those with certain chronic medical conditions are particularly susceptible. Pregnant women have also been found to be at increased risk of the complications of flu. Some people may need hospital treatment and a number of mainly older people die from influenza each winter.
Flu is a highly infectious illness. A person carrying the virus can spread the illness by coughing or sneezing. A person can spread the virus from 1-2 days before they develop symptoms and for up to a week after symptoms develop.
Flu symptoms hit you suddenly and severely. Symptoms of flu include
- sudden fever
- myalgia (muscle pain)
- sore throat
- non-productive dry cough
It can be difficult at times to tell between the common cold and flu. A cold is a much less severe illness than flu. The flu symptoms come on suddenly with fevers and muscle aches. A cold usually starts gradually with symptoms of a sore throat and a blocked or runny nose.
Table of Symptoms
The following table provides information on how to distinguish between seasonal flu and cold symptoms.
|Fever High||fever lasts 3-4 days||Rare|
|General Aches Pains||Usual||Often severe or slight|
|Fatigue Weakness||Can last up to 2-3 weeks||Quite mild|
|Extreme Exhaustion||Early and prominent||Never|
|Chest Discomfort||Cough Common can be severe Mild to moderate||Hacking cough|
Anyone can get the flu but it is more severe in people aged 65 years and over and anyone with a chronic medical condition. Chronic medical conditions include chronic heart conditions, chronic respiratory disease, diabetes mellitus and immunosupression due to disease or treatment (including those undergoing cancer treatment). Pregnant women have also been found to be at increased risk of the complications of flu. Also, residents of nursing homes and other long stay institutions, healthcare workers, carers and persons with a body mass index (BMI) of over 40 are most at risk. Finally people with regular close contact with poultry, water fowl or pigs are also more at risk of contracting influenza. These groups of people are targeted for influenza vaccination.
Flu can be prevented by vaccination. Flu vaccine is a safe, effective way to help prevent flu infection, avoiding hospitalisation, reducing flu related deaths and illnesses.
Each year the seasonal (annual) flu vaccine contains three common influenza virus strains. The flu virus changes each year this is why a new flu vaccine has to be given each year. This year’s flu vaccine contains the Swine Flu strain.
This year’s seasonal flu vaccine contains 3 strains of flu viruses as recommended by the World Health Organization (WHO) and has been manufactured in a similar way to previous seasonal vaccine. The three strains are:
- A/Michigan/45/2015 (H1N1)pdm09 – like strain (A/Michigan/45/2015, NYMC X-275) 15 micrograms
- A/Singapore/INFIMH-16-0019/2016 (H3N2)-like strain (A/Singapore/INFIMH-16-0019/2016, NIB-104) 15 micrograms
- B/Colorado/06/2017-like strain (B/Victoria/2/87 lineage) (B/Maryland/15/2016, NYMC BX-69A) 15 micrograms
per 0.5ml dose
Vaccination is strongly recommended for:
- persons 65 and over
- those with a long-term medical condition such as diabetes, heart or lung disease
- people whose immune system is impaired due to disease or treatment (including those undergoing cancer treatment).
- healthcare workers
- residents of nursing homes and other long stay institutions
- persons with a body mass index (BMI) over 40
- pregnant women. (can be given at any stage of pregnancy)
- people with regular close contact with poultry, water fowl or pigs
The Seasonal flu vaccine helps the person’s immune system to produce antibodies to the flu virus. When someone who has been vaccinated comes into contact with the virus these antibodies attack the virus.
Seasonal flu vaccine prevents flu illness in approximately 70% – 90% of people.
The effectiveness varies depending on the age and health of the person being vaccinated and the strains of flu virus that are circulating. Older persons and those with certain long term diseases have lower immune responses so the vaccine may not be as effective but it will still prevent severe illness and hospitalisation.
Swine Flu is a new flu virus that first emerged in April 2009. As most people did not have any immunity against this virus it spread rapidly worldwide and infected a large number of people. It is also known as Pandemic H1N1 (2009). Swine Flu infected in particular young children, pregnant women, women up to 6 weeks after giving birth and those under 65 years with long term medical conditions.
In the Northern hemisphere the flu season lasts from October to the end of April. Flu vaccine is recommended for all those in the at risk groups until the end of April Women who become pregnant at ant stage during the flu season should get flu vaccine.
Seasonal flu vaccines have been given for more than 60 years to millions of people across the world. Reactions are generally mild and serious side effects are very rare. The seasonal flu vaccines cannot give you the flu.
No. There is no thiomersal in the vaccine used in the 2017/2018 flu campaign
No, flu vaccine will not give you the flu. Flu vaccine contains killed or inactivated viruses and therefore cannot cause flu. It does, however, take 10 – 14 days for the vaccine to start protecting against flu.
The vaccine should be given in late September/October each year to give yourself the best chance of preventing the annual flu.
The most common side effects will be mild and will include soreness, redness or swelling where the injection was given. Headache, fever, aches and tiredness may occur. Some people may experience mild sweating and shivering as their immune system responds to the vaccine but this is not flu and will pass in a day or so.
The vaccine starts to work within two weeks.
The vaccine should not be given to those with a history of severe allergic (anaphylaxis) reaction to a previous dose of the vaccine or any of its constituents.
People with egg allergy can get seasonal flu vaccine. This may be given by your GP or you may need a referral to a hospital specialist.
There are very few reasons why vaccination should be postponed. Vaccination should be re-scheduled if you have an acute illness with a temperature greater than 38°C.
This is an infectious viral infection of birds and less commonly pigs.
Avian or bird flu due to the H5N1 virus has spread rapidly throughout poultry flocks in Asia and more recently to Eastern Europe. It is proving difficult to eradicate in birds.
Humans are rarely affected with avian/bird flu and this has mainly happened through close contact with live infected birds or their faeces.
Seasonal flu vaccine doesn’t protect against avian influenza and there is no vaccine currently licensed against avian influenza.
If you are over 65 or have a long term medical condition you should also ask us about the pneumococcal vaccine which protects against pneumonia, if you have not previously received it.
Keep well this winter
- Eat well: eat at least one hot meal a day.
- Keep warm: wear several layers when outside and keep at least one room heated during the day.
- Keep active.
- Get vaccinated.
You can download other information materials below for this years campaign.
- Public Flu leaflet – English version
- Pregnancy Flu leaflet – English version
- Healthcare Worker Flu leaflet – English version
- Royal College of Physicians of Ireland Immunisation Guidelines for Ireland
Health Protection Surveillance Centre website http://www.hpsc.ie/hpsc/A-Z/Respiratory/Influenza/
Centers for Disease Control and Prevention-Epidemiology and Prevention of Vaccine Preventable Diseases “The Pink Book-12th edition. April 2011 available at http://www.cdc.gov/vaccines/pubs/pinkbook/index.html
Centers for Disease Control and Prevention-Parents Guide to Childhood Immunization – 2010- available at http://www.cdc.gov/vaccines/pubs/parents-guide/default.htm#pguide
Department of Health UK. Immunisation against infectious diseases “The Green Book”2006 and subsequent updates available at http://www.dh.gov.uk/en/Publichealth/Healthprotection/Immunisation/Greenbook/DH_4097254”