Plague is a disease of an infectious nature. This anthroponous disease affects the lymphatic system, lungs, skin and other organs. It has been known since ancient times and in different centuries during epidemics claimed thousands and even millions of lives.
Plague is a particularly dangerous disease. Its causative agent is a bacterium from the genus Iersinia (Pasteurella) pestis. Plague microbe belongs to the family of enterobacteria. There are various foci of this disease (natural, urban). Under
natural conditions , wild rodents are a natural reservoir of pathogenic yersinia. These are gerbils, gophers, hamsters. In urban settings, the disease is spread by gray, red and black rats. But this is a reservoir of infection. The plague carrier is a common rat flea.
Pathogens enter the bloodstream with feces of parasites through scratching. Pulmonary form is transmitted from person to person. In general, infection occurs through direct contact with a living or dead animal or with products and household items that are seeded with yersinia. Less common are cases with an airborne transmission mechanism.
Directly at the site of introduction of the plague microbes, no pathological changes were observed. Plague is a disease that primarily affects the
lymph nodes. Therefore, the entire infectious process will develop there. In the lymph node closest to the entrance gate, small patches of necrosis form. This is the result of the action of strong plague “mouse” toxin on body tissues. Further, the patient develops periadenitis. The affected lymph node - bubo - increases in size, possibly its suppuration, followed by opening.
The development of such a form of infection as pulmonary plague is somewhat different . The disease occurs when pathogenic bacteria are introduced from foci (buboes or skin) with blood flowing into the lungs of a person. As a rule, this is a secondary form that develops against the background of skin or bubonic plague. In this case, the patient has a complication in the form of a hemorrhagic-necrotic infectious process. Secondary pulmonary plague proceeds as pneumonia.
Perhaps in medicine there are not many diseases that are more dangerous than the plague. The signs of the disease are very specific and depend on the location of the pathogen. The incubation period is usually no more than 6 days. The disease almost never proceeds in a chronic form, it develops with lightning speed. The first sign is acute intoxication. Patients are worried about severe headache, there are multiple petechiae. The spleen and cardiovascular system are also affected. The skin form of the disease is very rare. More often observed bubonic plague. With this clinical form of the disease, persistent and extensive inflammation in the lymph node forms. So-called buboes are formed. They are very painful on palpation. With the septic form, the formation of not one, but several foci of infection is noted. Plague disease in humans (a photo of the clinical picture can be found in medical guides) is characterized by high mortality and the ability to cause outbreaks of epidemics. But it is worth noting that in the last 50 years it was recorded only in some African countries.