Almost everyone knows it, a scratch in the throat, cold, headache and body aches: A cold is approaching. Colds are the most common widespread disease. For example, a 75-year-old man suffers from a common cold 200 times in his life. Since a cold usually takes seven to nine days, each person spends about two to three years of his life with cold and cough.
Flu or cold?
The distinction between a flu and a cold is not easy. The so-called banal cold - also called influenza - is like the flu caused by one of the more than 200 known cold viruses. However, there are characteristic differences:
- When flu occurs acute fever with temperatures up to 40 degrees Celsius, the person is significantly exhausted and suffers from severe head and body aches. The virus flu is a serious illness and calls per winter half year alone in Germany numerous deaths.
- In a cold, however, fever rarely occurs with such high temperatures. Almost all colds have runny nose. Headache, limb pain and sore throat, as well as coughing are common and annoying, but usually of lesser intensity than the flu. The symptoms of a cold usually resolve after a few days, the real flu usually lasts longer. Although the common cold is not one of the serious diseases, it significantly affects well-being and performance.
Infection by viruses
Colds are viral infections and can be caused by a number of different viruses (for example, rhinoviruses, adenoviruses). Viruses are tiny pathogens that need a foreign cell to propagate.
The infection is usually due to a droplet infection: the virus of an infected person whirling when sneezing or speaking through the air, the healthy person takes it through the airways. Even shaking hands with a person who has already contracted the virus can transmit them if they reach the nasal or ocular mucosa with the fingers after the handshake.
Most of the virus initially affects the nasal and pharyngeal mucosa. This swells and produces more secretions. The immune system of the body is alerted, general complaints such as fatigue and fever are the result.
Cold - a winter phenomenon?
Colds are usually associated with cold winter days. Alone the word cold already indicates that cold must have something to do with the disease. There is a logical explanation for this: Viruses spread very quickly under winter conditions. People spend more time in poorly ventilated and heated rooms, there is less sunlight that kills viruses.
Christmas stress and New Year's Eve parties and carnival celebrations with many visitors create the ideal conditions for a quick virus spread. In addition, the inhaled air is significantly colder in winter, cools the nasal mucosa and thus reduces their blood flow. Infectious agents have such a good chance of settling in the airways.
But you only get a cold if the viruses are present. Studies confirm that no cold can be triggered if the body has not previously been infected with viruses; not even with drafts and sudden cooling of the body. A hermit can therefore find it difficult to catch a cold.
Although the risk of getting a cold in winter is four times higher than in summer, a cold in the warm season is just as annoying. Especially air conditioners in offices or in airplanes dry and cool the nasal mucosa and thus promote the virus multiplication.