Infectious diseases arise due to the penetration of pathogenic (pathogenic) microbes. A pathogenic microorganism can cause damage if it has toxicity (virulence). In other words, it must be able to overcome the body's resistance by exhibiting toxic effects. The action of certain pathogenic microorganisms causes infectious diseases by excretion of exotoxins during their life. When exposed to other microbes, the release of toxins (endotoxins) occurs when their bodies are destroyed.
Infectious diseases are characterized by the presence of an incubation period. This is the time between the first infection and the onset of the first signs. The incubation period can last several hours or longer. In rare cases, several years. The duration of the incubation period depends on the type of pathogen and the method of infection.
It should be noted that infectious diseases are considered very natural phenomena occurring in human life. Some infections are replacing others, and with this new preventive problems arise. Today there is a fairly high degree of infectious lesions. Millions of new infections are recorded annually.
On the issue of infections, the importance and need for prevention cannot be overlooked. There is a group of infections that only the vaccine can provide protection against. At the same time, immunoprophylaxis of infections is aimed at enhancing immunity. To maintain it, re-vaccination is necessary. First of all, such prevention is carried out among children susceptible to infections with weakened immunity. They most often have acute infectious diseases. In some cases, antibiotics and chemotherapy are used as a preventive therapy to prevent infections. Before conducting preventive measures, an examination by a therapist or pediatrician is necessary.
Many infections are toxic. With such infections, the vascular system of the body is often affected. In some cases, with a toxic infection, developing vascular insufficiency can take a very severe course, becoming, in some cases, the cause of death. Moreover, under the influence of some infections, the venous inflow decreases due to a sharp drop in vascular tone and the movement of blood in one or other depositing areas. Such a course is characteristic of pneumonia or typhus. The impact of other infections, in addition to the above lesions, contributes to an increase in permeability in the capillary walls and the exit of a part of the plasma from the channel of the vessel. Such manifestations are characteristic of foodborne infections, dysentery.
Infectious lesions contribute to the development of many diseases. Not timely preventive measures can lead to serious complications. The immune system ceases to cope with the attacks of microorganisms. Launched, untreated infections on time contribute to damage to the heart muscle. Reaching the human cardiovascular system, they contribute to the development of degenerative changes in the nervous regulation of the heart.
Some untreated infections, such as gonorrhea, brucellosis, tuberculosis, can cause the development of a disease such as infectious polyarthritis. With this chronic ailment, articular damage is crucial. In the development of this type of disease, a stage is noted at which a change in the articular soft tissues and synovial membrane occurs. The second stage includes the development of abundant granulations with cartilage resorption (resorption) and fibrous ankylosis. Fibrous bone ankylosis is referred to the third stage. In the case of ignoring the treatment of the disease, a violation of the articular function may occur.