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What is it and how is it spread?

Influenza, more commonly known as the flu, is an infectious disease caused by a virus that affects the nose, throat, airways and lungs.1 The infection is spread from person to person through the air when infected people cough or sneeze, meaning it spreads quickly in crowded and enclosed areas. You can also catch the flu from touching things which are carrying the virus, such as furniture that an infected person has sneezed on, and then touching your nose or mouth.2

There are three different types of influenza virus – types A, B and C. Types A and B cause most illness, and the yearly epidemics of the flu are mainly caused by type A. The most common time to catch flu in the northern hemisphere is between November and April, whereas in the southern hemisphere it is between April and September.1

In 2009, a type of influenza A that originally came from pigs, commonly known as 'Swine flu', caused an influenza pandemic (a worldwide epidemic).2

Who is at risk?

The flu can affect people of all ages. How it affects different age groups can change each year, depending on the type of flu that is going around. People who are at the most risk include older people, very young children and infants and people with health problems.2

If you are visiting a country during its flu season, you are just as likely to catch the infection as the local people.1

What are the symptoms?

Symptoms of the flu normally include a fever, chills, headache, muscle pain and extreme tiredness, blocked nose and a sore throat.1,2

How can it be prevented?

The most effective way to prevent getting the flu and to stop it from spreading is vaccination. Flu vaccines can protect you against types A and B of the virus.2 If you are in a clinical at-risk group, try to ensure you are vaccinated before you travel. If you are travelling to the southern hemisphere during their flu season and you are in a clinical at-risk group, you may want to consider arranging to have a vaccine at your destination.1,2

Your doctor should assess your risk of getting the flu if you are travelling to a country during flu season. 

How is it diagnosed and how can it be treated?

Diagnosis is made based on the symptoms you are showing. The infection will normally go away by itself after about a week, but in special cases you may be given drugs to help treat the infection.1,2

Where can I get further information?

Make sure you contact your GP or travel health practitioner in plenty of time before you travel to discuss the ways you can help to keep yourself healthy whilst away. You should try and contact them at least 4–6 weeks before your trip.

After your trip, you should contact your GP if you develop a fever or notice any other unusual symptoms.

  1. Fit For Travel. Influenza. Available at: Accessed August 2017.
  2. Travel Health Pro. Seasonal Influenza. Available at: Accessed August 2017.

Date of preparation: November 2017