Seasonal and pandemic influenza

What is influenza (flu)?

Seasonal flu normally occurs during the winter months. It is a much more serious illness than a cold and it usually results in having to go to bed for several days, feeling very poorly with a high temperature and aching limbs.

Older people and people with chronic medical conditions (such as asthma) are most at risk of developing complications if they catch the flu. This is why the seasonal flu vaccination is recommended to these groups of people each year.

For full information on NHS eligibility please visit the NHS website:

NHS Vaccinations - Who should have the flu vaccine? (external website)

Seasonal Flu Vaccination is now available from many local pharmacies, please visit NHS Find Services (external website) to check availability at your local pharmacy.

What is a flu pandemic?

A pandemic happens when a completely new strain of flu virus develops which no-one has built up any immunity against. As a result, the new flu strain spreads very rapidly around the world and affects many people. This has been seen recently with the outbreak of swine flu. 

A pandemic could start at any time of the year. Existing vaccines will not protect against the new strain and new vaccines take time to develop, and so are not available immediately. The symptoms of a pandemic flu strain are likely to be similar to seasonal flu but may be more severe and cause more complications.

Historically, pandemic flu outbreaks have happened every few decades. The 2009 Swine flu outbreak was an example of a relatively mild pandemic. Health organisations in the UK and around the world are closely monitoring flu viruses to anticipate a pandemic, and very detailed plans are in place to help people to respond if and when a pandemic happens.

What are the signs and symptoms of seasonal flu?

The signs and symptoms of seasonal flu are:

• high temperature (38.5c or higher)
• headache
• tiredness
• chills
• aching muscles
• sore throat
• loss of appetite.

The incubation period (time between contact with the virus and the onset of symptoms) ranges from one to four days. Most people will feel ill for around a week and will probably feel 'washed out' for a few days afterwards.

For most people, flu is just an unpleasant experience but it can lead to serious illnesses, like bronchitis and pneumonia, which can be life-threatening.

How do you catch flu?

Flu is mostly caught by breathing in air containing the virus. The virus is passed into the air when an infected person coughs or sneezes and others can then breathe it in.

Flu is highly infectious and can spread very rapidly from person to person. People are most infectious soon after they develop symptoms, though they can continue to spread the virus for around five days – and longer in children.

What you should do if you develop flu-like symptoms?

• If at work go home immediately (after informing your manager/supervisor)
• Stay at home and do not go to work or school until you are fully recovered
• Take medicines, such as paracetamol, to relieve the symptoms – always follow the instructions on the medicines
• Drink plenty of fluids
• For advice on treatment, contact NHS Direct on 111
• Only see your doctor if you get complications (e.g. chest infection) or a worsening of an existing chronic condition.

What you can do to protect yourself and others from flu?

• Use a tissue to cover your nose and mouth when coughing and/or sneezing
• Dispose of the tissue promptly, by bagging and binning it, then wash your hands
• Clean hands frequently with soap and water, especially after coughing, sneezing and using tissues. An alcohol hand rub could be used as an alternative for cleaning hands if water is not available
• Avoid touching your mouth, eyes and nose, unless you have recently cleaned your hands
• Use normal household detergent and water to clean surfaces frequently touched by hands
• Wash your hands when arriving back from outside activities, before and after direct contact with contaminated surfaces, after contact with bodily secretions, before handling food, before eating or smoking
• Make sure all members of your family follow this advice.

Where can I find out more information?

Further advice is available from the NHS website:

NHS - Influenza (external website)

Alternatively, you can telephone NHS Direct on 111.