Influenza

Influenza or 'flu' is a respiratory illness associated with infection by influenza virus. Symptoms frequently include headache, fever, cough, sore throat, aching muscles and joints.

Seasonal and Pandemic Influenza
Seasonal flu occurs typically in the winter months between December and March, allowing time to identify the virus and administer a vaccine in advance, whereas pandemic flu can occur at any time of the year allowing no time for a vaccine to be prepared because the virus is completely new. Seasonal flu most seriously affects the elderly and vulnerable groups while pandemic flu can affect people of any age. The symptoms of pandemic flu are similar to seasonal flu. However, in the case of pandemic flu, these symptoms are likely to be worse, resulting in more severe illness.

Avian Influenza
A severe form of avian influenza or ‘bird flu’ – called H5N1 – has affected poultry flocks and other birds in several countries since 2003. As of 5 February 2007, 271 people have caught the infection, as a result of close and direct contact with infected birds in domestic third world conditions. There is no firm evidence that H5N1 has acquired the ability to pass easily from person to person.

Links to more specific information in differing kinds of Influenza can be found on within the subsequent pages.