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Seasonal Flu

video

Introduction

Seasonal flu, which is also known as influenza, is a very infectious disease that usually happens in the winter months due to a virus. It occurs every year, and flu viruses are constantly changing.

Antibodies are types of proteins that fight germs that have come into your body. Your body produces antibodies to protect itself when you get the flu virus. These antibodies are able to remember the same flu virus and fight it if it enters your body again.

Unfortunately, flu viruses are frequently able to change (mutate) into a different type/version every year. This means that if you were to get a different type/version of the flu virus, your body would not recognise it and would get the flu infection. This is the reason why people get repeated flu infections.

There are different types of flu; the three main types are:

  • Type A - occurs every two to three years and is more serious than type B. The virus is likely to mutate into a different version to which people have no resistance.
  • Type B - generally causes a less severe illness and is responsible for smaller outbreaks. If you have been infected with this, your immunity to further flu B infections will last for many years. Flu B mainly affects young children.
  • Type C - usually causes a mild illness similar to the common cold.

How the infection is spread

The virus can be spread via small droplets from the nose and mouth e.g. through a cough or sneeze through the nose and mouth. These droplets can actually survive for few hours on surfaces such as tissues and on hands. So, if someone else touches this surface, they can become infected. The droplets can travel in air and spread to others by them breathing it in, thus it is important to cover your nose or mouth when coughing or sneezing.

Symptoms

The seasonal flu symptoms include:

  • Fever
  • Dry, chesty cough
  • Tiredness
  • Headache
  • Chills
  • Runny or blocked nose
  • Sneezing
  • Sore throat
  • Shortness of breath or cough
  • Loss of appetite
  • Aching muscles/limb or joint pain
  • Diarrhoea or stomach upset
  • Difficulty sleeping

There are some people that are more likely of becoming ill (although everyone is at risk).

These include:

  • Very young or elderly people
  • People with existing medical conditions such as asthma or diabetes
  • People who are immunosupressed (their immune system is 'dampened' down) by certain medications

Flu virus in some children with specific long-term health conditions (such as chronic [long term] heart and liver problems, sickle cell disorder and others) can be more serious. A serious complication associated with flu is a bacterial chest infection potentially developing into pneumonia. Some other rare complications include:

  • Tonsillitis
  • Otitis media (a build-up of fluid in the ear)
  • Septic shock (infection of the blood that causes a severe drop in blood pressure)
  • Meningitis (infection in the brain and spinal cord)
  • Encephalitis (inflammation of the brain).

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Acknowledgements
Catch it, Bin it, Kill it.
DH information leaflet http://www.direct.gov.uk/prod_consum_dg/groups/dg_digitalassets/@dg/@en/documents/digitalasset/dg_178687.pdf
NHS Choices website
http://www.nhs.uk/conditions/flu/Pages/Introduction.aspx
NHS Scotland, NHS wales, DHSSPS,NHS (2009)
Seasonal flu. Why you should have the vaccination http://www.nhs.uk/Conditions/Flu-jab/documents/Seasonal%20Flu%20Vaccination%20leaflet.pdf