Flu (influenza) - immunisation

Influenza, commonly known as the flu, is caused by a highly contagious virus that is spread by coughs and sneezes. Every year it causes widespread illness in the community (epidemics and pandemics). Annual immunisation is recommended for older people and those ‘at risk’ to avoid serious complications, such as pneumonia, that may arise as a result of contracting the virus.

Influenza epidemics occur, on average, every three years. An epidemic is when there is an increased incidence of the disease among a group of people, for example the elderly. Influenza pandemics have occurred three times in the past 100 years. A pandemic is when the disease affects a large proportion of people in a geographic region or continent.

Serious side effects or allergic reactions to the vaccine are rare. If you are concerned about your reaction or your child’s reaction to any vaccine, see your doctor immediately.

Immunisation can prevent serious complications
Influenza viruses change every year because the influenza virus has a unique ability to change its surface structure. This allows it to escape recognition by the body’s immune system. So a new vaccine needs to be developed and given each year.

Immunisation should occur between March and May, before the onset of the flu season. Most cases of influenza occur within a six to eight-week period during winter and spring. Protection develops about two weeks after the injection and lasts for up to one year.

Influenza vaccine cannot give you a dose of flu because it contains no live virus. However, some people may still contract the flu because the vaccine may not always protect against all strains of the influenza virus circulating in the community.

High-risk groups should be immunised
In Victoria, under the National Immunisation Program, an annual influenza immunisation is provided free of charge for:

• Everyone aged 65 years or older
• Kooris and Torres Strait Islanders aged between 15 and 49 years with health risks
• Kooris and Torres Strait Islanders aged 50 years or older
• All public hospital outpatients and inpatients with high-risk factors
• Public hospital staff who provide direct care to patients.

• Anyone from six months of age with heart disease, chronic lung disease, chronic neurological conditions, impaired immunity and other chronic illnesses such as diabetes, kidney disease and haemoglobinopathies
• Residents in nursing homes or other chronic care facilities
• Staff in private hospitals, long-term care facilities or nursing homes
• People who live with, or care for, someone who has a chronic illness or is aged
• Severe asthmatics who require frequent hospital visits
• Pregnant women
• Children on long-term aspirin therapy
• Anyone travelling as part of a group
• Workers, particularly those in workplaces that provide essential services
• People involved in the commercial poultry industry
• Workers in other ‘high risk’ industries.

• Is unwell (temperature over 38.5˚C)
• Has had a serious reaction to any vaccine
• Has had a severe allergy to anything
• Has had an anaphylactic allergy to eggs – this is because the virus used in the vaccine is grown in eggs
• Is under six months of age
• Has had Guillain-Barre syndrome.

• Pain, redness and swelling at the injection site
• Low-grade fever
• Muscle aches
• Drowsiness or tiredness.

• A cold, wet cloth placed over the injection site
• Paracetamol to reduce any fever – check the label for the correct dose (especially for children)
• Extra fluids to drink
• Appropriate clothing – do not overdress.

• Your doctor
• Your local council immunisation service
• Nurse-on-Call Tel. 1300 606 024 – for expert health information and advice (24 hours, 7 days)
• Your local community health centre
• Immunisation Program, Department of Health Victoria Tel. 1300 882 008
• The emergency department of your nearest hospital
• National Immunisation Infoline Tel. 1800 671 811

• Influenza is an epidemic disease that causes widespread illness every year.
• Influenza immunisation is recommended for people in known high-risk groups.
• The vaccine cannot give you a dose of flu because it contains no live virus.

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