As to the origin of the word flu or influenza there’re several versions. According to one version it appeared after the epidemic of flu in Italy in the 15 century. Italians thought that it happened because of influence of the stars (influence – influenza).
As to the origin of the word flu or influenza there’re several versions. According to one version it appeared after the epidemic of flu in Italy in the 15 century. Italians thought that it happened because of influence of the stars (influence – influenza). According to the other version it takes its origin after the Latin word influere which stands for interfere. The first mentions about flu appeared in 412 B.C. The illness similar to flu was first described by Hippocrates. First mentioned pandemics of flu happened in 1580. The virus of flu was discovered in 1931 by Richard Shope.
The virus of flu is the virus from the group of mixed viruses (Myxovirus influenzae). There’re three types of this virus – A, B and C which differentiate in qualities. But even the virus of one type is inclined to variations, for example A1, A2. For example, from the time of discovery of the virus of group A it changed a lot. New variants of this virus appeared (A2/Hong Kong, A2/Victoria, A2/Port Chalmors and others). That is the reason of broad spreading of flu and developing of the epidemics. The virus of man’s flu is also dangerous for hamsters, mice and rats. Some other animals can be infected with this virus as well (pigs, horses, birds etc.)
The source of infection is an ill person, especially in the climax of disease. The most dangerous are the ill people with light or disguised forms of flu. Cause they can contact with many other people and spread the illness quickly. Moreover the existence of flu without any symptoms is proved.
The transference of infection is carried out by sneezing and coughing. As to the transference of the infection through the things which were used by ill person it is not very often due to low firmness of the virus.
Susceptibility of the flu is very high and it is possible for everyone to fall ill with it. For the infecting the short contact with an ill person is enough. After having had the illness the person can get immunity but it is not constant (after the flu A – 2 years in average, after the flu B – 3 years). But still even the immunity can protect only from the very form of flu which person suffered from.
The epidemic of flu may develop due to the little distance between the lodging of the people, migrations, unsatisfactory hygienic state in places of the public usage. The epidemics may develop during any season, but oftener during the coldest months (in winter, spring), it’s typical for the northern hemisphere.
Children and teenagers are more susceptible to the illness than adults. The babies less than 6 months have the immunity which they’ve got from their mothers. The flu is especially dangerous and can be spread quickly if it’s the new type of virus or the people were not infected with this type of virus for a long time.
As usual the epidemic of flu spreads very quickly, in a short period of time the 20-30% of population can fall ill with flu. During very big epidemics – 50-70% and even 100%.
The flu can cause pandemics as well. For example during pandemics in 1890 30-50% of the world population suffered with flu. In 1918-1919 during the pandemics 500 000 000 suffered from flu, 20 000 000 of them died.
This happened due to inclination of flu to variations. The scientists foretell the mutations of flu A due to the combinations of the man’s flu with the animal’s flu.
Re: The Flu