Flu or grippe is known as a contagious disease caused by flu virus (very small germ). When flu virus is being emitted into the air - it can be inhaled by anyone who is close by to the sick person. Flu viruses are 80 to 120 billionths of a meter in diameter. They have a very shifty nature that's why they are able to invade the entire immune system. Very often the rna virus (its genetic material is RNA) is the cause of flu. The first flu virus is known to be identified in the 1930s. Later doctors learned more about this virus and according to modern medical practice three flu types have been identified: type A, type B and type C. Besides them, several other kinds of flu or grippe are distinguished (for example, Spanish flu, Asian flu, Swine flu, Hong Kong flu, etc.). Type A is considered to be the most common flu type causing the majority of serious flu epidemics. The disease produced by type B is usually milder. On the other hand, type C has never been connected with large flu epidemics. Speaking about flu or grippe it's impossible not to mention the common flu symptoms such as fever, body aches, chills, couch, headaches, loss of appetite, ache in arms, etc. The tissues of respiratory tract become inflamed and swollen. A sore throat, nausea and burning eyes are possible. The temperature of the flu sufferer usually rises up to 104 degrees F during the first two-three days. Then the temperature drops. But still the person's condition is likely to remain exhausting. Who runs a risk of getting flu or grippe? Anyone does. But different people will have various symptoms and disease's severity degree. The highest risks of getting flu have the following categories of people: -people with such chronic diseases as bronchitis, bronchiectasis, tuberculosis, emphysema, asthma, cystic fibrosis, etc.; -people with heart or kidney disease; -people with severe anemia; -people with diseases that depress immunity; -people over 50 years of age; -children of 6-25 months of age and people around them. Even if you don't belong to the mentioned categories of people you should be aware that flu can cause very severe complications and sometimes even be fatal. The majority of complications are bacterial infections. The most common serious complication of flu or grippe is pneumonia. At the same time inner ears and sinuses may become painful and inflamed. How to prevent flu or grippe? The majority of medical experts nowadays recommend flu vaccination. Be aware that different types of vaccines are made every year (depending on the flu virus type and severity). The vaccine is prepared from inactivated flu viruses which are unable to cause the disease. Most people have no reaction to vaccination. Sometimes, there may be a swollen, reddening and tendering of the area where vaccination was made. Other side effects may rarely appear. For example, children or adults who haven't been exposed to flu virus before may experience tiredness, fever and sore muscles. If you do have flu or grippe we advise that you consult your doctor regarding the most appropriate treatment method.