The influenza virus, commonly called the flu, causes an infection of the body's respiratory (breathing) system which affects the nose and throat, and sometimes the ears, sinuses and lungs.
The flu can occur in epidemics, where a large number of people are infected at a time. Influenza epidemics are most common in the winter, though you can catch the flu all year round.
What are the symptoms of influenza?
These are the most common flu symptoms:
• Sudden fever (over 38°C)
• Runny or congested nose
• Sore throat
• Feeling tired
• Aching muscles and joints
• Diarrhoea or vomiting
Flu symptoms are in some ways similar to those of a common cold, but they're more severe and longer lasting. They also appear faster and affect more of your body than a cold which tends to be localised around the nose, as well as having a more serious effect on your energy levels. If you have flu, you're very unlikely to be able to go to work or continue your daily activities. You may have flu symptoms for two weeks, and fatigue for a few weeks after.
How is the flu transmitted?
When a person with flu sneezes or coughs, tiny droplets containing the virus are released in the air. If inhaled, these cause infection.
The flu virus can live on hands and surfaces such as door handles for 24 hours. You can get flu if you touch an area with the flu virus on it. Flu is infectious from the day you get symptoms until around five days after. However, you may have been infected with flu for up to two days before you get the first symptoms.
How can I manage my symptoms?
If you think you have the flu, make sure that you drink plenty of fluids. Rest as much as you can and stay away from work or school to avoid infecting other people, and allow yourself to recover. You can also take a cold and flu preparation to help with symptoms. These medicines usually contain any of the following:
• Paracetamol or ibuprofen to help with headaches and fever
• Antihistamines to help control a runny nose, and help you sleep – ask your pharmacist for advice on which antihistamines are most suitable for this
• Decongestants to help relieve nasal congestion
• Cough suppressants
• Mucolytics to help thin mucus, making it easier to cough up
It's best to speak with your pharmacist to find the best preparation for your symptoms and medical history.
When should I see my Doctor?
Make an appointment with your Doctor if:
• Your symptoms persist for more than seven days or get worse
• You have a temperature for more than three days
• You are unable to keep fluids down due to vomiting
• You are pregnant or elderly
• You suffer from a chronic health condition like diabetes
• If you're over 65
How can I prevent catching the flu?
If a relative or friend has the flu, make sure that you offer help as long as you're healthy yourself – you can still visit and provide care while staying safe. Wash your hands frequently with warm water and soap, and avoid touching your face. Keep physical contact with them to a minimum. You should also ask the person with flu to cover their nose and mouth with a tissue when they cough or sneeze, and make sure any used tissues are binned immediately. Helping a person with flu stay at home by running errands for them can prevent the influenza virus from spreading.
You could also have a yearly influenza vaccination, or 'flu jab'. Scientists prepare this vaccination against strains they think will be most common that year. This means that if you get infected with a different strain than those in the jab, you can still get the flu but the severity and duration of your illness may be reduced.
What are the next steps?
• Consider getting the flu vaccination to help prevent catching the flu
• Rest and drink plenty of fluids if you get flu
• Ask your pharmacist or Doctor for advice if your symptoms do not get better