What is Influenza?
The influenza virus is spread through respiratory droplets and aerosols from person to person. One of the commonest infections suffered by overseas travellers, influenza can affect people travelling to any part of the world.
FAQs
In which months is influenza most common?
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In temperate regions, influenza occurs more commonly in winter and adjacent months. The annual flu season varies from year to year, but commonly occurs from November to April in the Northern Hemisphere and April to September in the southern half of the globe. In tropical regions, influenza can occur in epidemics throughout the year.
Do I need a flu vaccine before my trip?
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The formulation of influenza vaccines is updated each year to reflect changes in circulating strains of the virus. For non-travellers, it is therefore recommended to have a flu shot every year. For travellers, your doctor may recommend an additional dose prior to travel, even if your last dose was less than 12 months ago. This will depend on the level of flu transmission at your destination, your own personal risk profile and other factors.
How long before I travel do I need to have my flu shot?
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Around two weeks is usually sufficient time for your body to develop its maximum immune response after vaccination.
What are the side effects of influenza vaccination?
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Side effects of vaccination tend to be minor such as redness, pain or swelling the injection site. Less than 10% of people experience fever, muscle aches or fatigue for one to two days after the injection. Severe allergic reactions are very rare.
What to Know
Influenza symptoms
After an incubation period of one to four days, symptoms begin including cough, sore throat, fever and muscle aches. Many people experience debilitating fatigue and a few go on to have severe illness or complications like bacterial pneumonia. Risk factors for complications include extremes of age, pregnancy, underlying health problems of many types including asthma, chronic lung disease and compromised immunity.
Influenza diagnosis and treatment
The diagnosis can be made using PCR testing of swabs from the upper respiratory tract. Antiviral medication is used for people with severe or progressive illness, those with complications or at risk of them, and those who are in close contact with people at risk of complications.
Influenza prevention
In Australia, annual influenza vaccination is recommended for anyone over the age of six months. It is particularly beneficial for travellers to areas currently experiencing an influenza outbreak, those who have risk factors for complication of influenza infection (including those over 65 years old), people travelling in large groups (especially cruises), and those participating in mass gatherings.