Flu – what is it and what are the symptoms

Flu – General information


The flu, or influenza, is a respiratory infection caused by two types of viruses, most commonly in cold seasons.

The common cold is also a viral infection, but is less serious than the flu. Both have similar symptoms, except that flu is accompanied by a long-lasting fever, and severe complications can arise, such as pneumonia.

Over the century, the viruses for cold and flu have evolved rapidly, which has made them resistant to medicine and some antibiotics.



It is essential to recognize flu symptoms as early as possible, because there are medications that can help if taken rapidly. It is better to be alert since the start of the flu season – autumn – when the most cases of school children with flu are reported. Flu symptoms set on quite rapidly, a strong indicator being the fever and muscle pain. Generally, the flu symptoms are quite debilitating and a generalized weakness of the body sets in, along with cough, headaches. The symptoms are similar in children and adults.

H1N1 swine flu can also cause gastrointesintal problems: in young children vomiting is also an indicator.

Unlike the common cold, flu can cause severe complications: pneumonia, other infections of the respiratory system. Complications can worsen if the patient has chronic conditions like asthma or diabetes or sufferes from heart problems.

New types of flu


There are three kinds of flu viruses (A, B and C) which cause mildly different symptoms. In the late 70’s, about 3.000 deaths were associated with the flu. By the 2006-2007 flu season, this number has risen dramatically up to 49.000, according to a study made by the Centre for Disease Control.
The type A of flu is a virus also common among animals, especially birds. It is rapidly transmitted and causes large flu epidemics; it is also hard to treat or to prevent as it develops quickly.
The type B flu manifests itself only in humans. It does not have severe symptoms and it is not specific to pandemics, but it can become very harmful, especially if complications emerge.
The type C flu is the less severe virus type. It does not affect animals.


Bird flu

Anually, the flu viruses modify, change and evolve, therefore, one single vaccination against flu will not protect you forever. The vaccines have to be modified accordingly, in order to be effective. The vaccine is designed so that the body will generate antibodies against type A and B.
The bird flu is a type A virus. It has several subtypes, and some of them are very dangerous, causing even large epidemics or pandemics. The most exposed to infection are the people in rural areas, that grow birds among their livestock, and where the virus can spread very quickly. Cooking does kill the virus, however. The virus can only be spread among domesticised birds, as wild birds are immune to it.

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