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The flu virus - what didn't we already know about it?
Medical expert of the article
Last reviewed: 06.07.2025
More than 95% of all acute infectious diseases caused by viruses and bacteria are flu and colds of various origins. They have already affected more than 15% of all people in the world. This is more than 500 million people every year around the globe. Of these, 2 million people say goodbye to this world because of the flu. Why are flu viruses so dangerous and what are they?
[ Such different flu viruses
The flu virus was first discovered in 1931. Two years later, English doctors officially described and identified it. Three years later, viruses began to be divided into subspecies - for example, flu with the causative agent of the B virus was identified, and in 1947, scientists isolated the flu virus by type C. What are the characteristics of different types of flu viruses?
The influenza A virus, which causes influenza, is one of the most common. It causes mild to moderate influenza. This virus is so easily transmitted from person to person and from animal to person that it can cause epidemics across entire cities (especially in ancient times). These epidemics are so large that scientists call them pandemics.
The B group virus has a simpler spread. For example, it does not cause pandemics, but can cause local outbreaks in a certain city or village. But there can be many such settlements, and not in one, but in several countries. Moreover, the influenza A virus and the influenza B virus do not interfere with each other and can manifest themselves in the same human society with equal intensity. True, the A virus is more likely to affect adults, and the B virus is more likely to affect children. But neither children nor adults are immune from the fact that either virus can visit their body.
There is also the flu C virus, which is not very well known to scientists, despite all the innovations of modern equipment. This virus is not transmitted to animals or from them to humans. Having become infected with this flu virus, a person may not even suspect what a serious disease he has, because he gets off with a slight malaise. The symptoms that appear when infected with the flu C virus may not appear at all or appear in a very mild form. The C virus can affect a person at the same time as the flu A epidemic.
How is the flu virus transmitted?
Very easy. You sneezed, coughed, said hello, or even worse, kissed an infected person, and you became infected with the flu just like him. The transmission route of the flu virus is considered to be airborne, and this is true for all three flu viruses. Pathogenic flora very quickly penetrates the body of another person, and you can become infected from a distance of up to three meters.
Therefore, do not go yourself or take your child to a group where there are sick people, and do not infect others. Isolation of the sick person is the only correct way out when infected with the flu virus.
The flu virus is an easy and very sneaky enemy that is best avoided. It is much easier than trying to get rid of it for a week or two.
How does flu manifest itself?
It is estimated that an ordinary person who does not get flu very often spends about a year in bed throughout his life because of this disease. During this time, the patient exhibits flu symptoms such as headache, weakness, fatigue, high temperature, cough, runny nose, dry mucous membrane of the throat and nose. The person feels absolutely exhausted because of the viruses that penetrate all body systems and poison it with toxins.
If the flu lasts for a long time, the viruses poison the body so much that a person develops complications. This is a disruption of the vital organs: kidneys, liver, heart, blood vessels, lungs. A person immediately after the flu also suffers from pneumonia, meningoencephalitis or tracheobronchitis.
Influenza viruses used to cause even more destruction – in 1580, historians recorded a global flu epidemic that took many lives. At that time, they did not know how to fight the flu virus. And even now, when there are many advanced medical technologies, people sometimes die from this disease. Therefore, it is worth getting vaccinated against the flu even before the peak of epidemics and maintaining personal hygiene, since the flu virus is transmitted by airborne droplets.