Why is flu more dangerous than cold?

Flu

Flu, more properly called influenza, is a disease caused by three basic viruses, know as A, B and C. In general, an infection from type A is more severe than B, and B is more debilitating than C. People with a C-type infection may believe they have only a cold: the two illness are almost impossible to distinguish.

Whenever we get a dose of flu means we will never get another because this virus is table. Unfortunately, A and B types procedure new strains of virus, which can penetrate our immune defences. And some of these invaders are extremely virulent.

The A type is particularly dangerous, because it constantly changes its form. The Spanish flu pandemic that began in 1918, the last year of World War I, killed an estimated twenty million people worldwide. The outbreaks of Asian flu in 1957 and Hong Kong flu in 1968 also were A-type infections. The B-type virus changes less often, but alters enough to cause trouble.

Flu is more dangerous than a cold because the A and B types pack some extra punches. One is their ability to bring crushing fatigue. As well, they induce fevers reaching to 40° c (104 ° f) and higher. The very young, the elderly and those with heart or respiratory problems are especially at risk.