The "real flu" is an infectious disease triggered by influenza viruses and occurs seasonally around the globe. In Germany, the flu wave usually begins between January and February, and causes several thousand deaths each year.
Typical symptoms of seasonal influenza are sudden fever and chills respectively, dry nervous cough, sore throat, muscle pain and headache. In addition, the infection may be accompanied by sweating, general weakness, sickness, vomiting and diarrhoea. However, only one third of all infected suffer from fever. Most cases involve light symptoms or are subclinical – infected people often do not even recognise that they have an influenza infection.
The highly infectious disease is primarily transmitted via droplet infection. Coughing and sneezing frees up pathogens that may travel short distances and reach other persons' respiratory systems or mucous membranes. Smear or contact infection is also possible, for example, via hands touching a contaminated surface and then mouth or nose. The time between being infected and the beginning of symptoms is between 1 to 2 days. Contagiousness starts with the occurrence of the first symptoms and lasts for an average of 4 to 5 days. The symptoms of the infection normally disappear within one week.
Severe forms of the disease, for example those involving additional pulmonary diseases, basically may occur in people of all ages. However, particularly elderly people, children, pregnant women, people with immunodepression and chronic diseases of heart, lungs or metabolism belong to the risk group. In case a severe course of a disease is suspected, the patient should be treated with antiviral drugs. The attending physician can diagnose influenza infections by a rapid test. For healthy people under 60 years of age, however, the treatment of symptoms usually is sufficient.
Active immunisation is an effective prophylaxis and should ideally be carried out in October or November. Later vaccination may be reasonable; however, the development of immunity needs around two weeks. Up to 90 per cent of all vaccinated healthy people do not acquire an influenza infection; for elderly people, this value is much lower. But for this group in particular, the vaccination is highly important to avoid complications and hospital stays. Also for children, pregnant women and people with chronic illnesses, active immunisation is advisable.
