Ignitions - General infection theory
First of all, the list of conditions under which an inflammation can arise is repeated and then the symptoms (symptoms) of local and general infections and the course of infectious diseases are discussed.
Conditions for ignition
The following conditions apply to ignition:
- Transfer of sufficient living (or viable) germs (millions!);
- The germs must end up in the right location. For example, Legionella pneumophila, the causative agent of Legionnaires' disease, can only harm the airways, not on the skin or in the gastrointestinal tract;
- The condition of the recipient (host) determines the resistance of the body and thus whether the germs are rendered harmless before there are enough to cause disease symptoms;
- The attack power (virulence) of the pathogen must be large enough to make the infected individual ill. For high virulence, a relatively small number is required before the body reacts with symptoms of illness. Child diseases are generally caused by highly virulent pathogens. There is 'no escape' if such micro-organisms make the neighborhood unsafe. The hepatitis B virus (HBV) is also very virulent.
Symptoms local inflammation
When the symptoms are limited to the place where the contamination took place, we call this a local inflammation. After the germs have invaded, all kinds of mechanisms come into operation. This involves tissue cells, but also various chemical substances play a role.
The symptoms of a local inflammation are:
- Redness (rubor);
- Swelling (tumor);
- Heat (calor);
- Pain (dolor);
- Disrupted function (functio laesa).
Symptoms general inflammation (disease)
If the symptoms of inflammation extend further than the place of the original infection, there is an (infection) disease. In addition to general symptoms, external symptoms can occur and regularly (invisible) functional disorders.
- General symptoms:
- Fever: body temperature of 38 ° C or higher. Between 37 and 38 ° C people speak of an increase;
- Itching: unpleasant sensation based on an extremely small pain stimulus that is experienced as itching;
- General malaise: a feeling of being sick, coupled with low appetite and fatigue.
2. External symptoms:
- Ulceration: inflammation on the surface of the skin or mucosa with little tendency to cure;
- Blistering: release of the epidermis, in which fluid accumulates on a further intact skin or mucosal surface (chickenpox);
- Rash: red discoloration of the skin or mucosa, sometimes in the form of individual spots or dots, but also in the form of a 'rush' or an even redness spread throughout the body;
- Yellow eye-white and yellow skin (jaundice).
3. Functional disorders in case of illness:
- Changes in heart, lung and brain function. The heartbeat frequency (pulse frequency) increases as the body temperature rises. The lungs need to take in more oxygen because of the increased burning in the tissues and the respiration frequency becomes higher. In case of high fever, the patient is often confused;
- Changes in kidney and liver function. In severe situations, a small amount of protein is often found in the urine. Under certain circumstances, liver function may decrease or there may be an accumulation of bile. This causes jaundice and indicates a serious complication;
- Changes in the blood picture. The number of white blood cells increases strongly within a few hours. In addition, the sedimentation rate of the blood cells increases. The higher the sedimentation rate, the more severe the inflammation / infectious disease.
Development of infectious diseases
There are various options for the course of an infection:
- Subclinical: the infection is so light that there are no obvious symptoms (symptoms);
- Acute: a sudden and usually severe infection;
- Chronic: a long-term process with only minor complaints;
- Lethal: the attack of microorganisms is so severe or massive that the host is unable to defuse the intruder in time. The host dies from the effects of the invasion by the microorganisms.