The plague is an acute infectious disease; characterized by severe intoxication, fever, lymph nodes, skin and lungs.
The causative agent is the plague bacillus, immobile, 0.5–1.5 µm in size, gram-negative, unstable outside the body. Disinfectants, boiling, antibiotics have a disastrous effect on her.
Plague refers to quarantine diseases. In natural foci, the sources and reservoirs of the pathogen are rodents. The main ones are marmots, gophers and gerbils; possible infection of people from rodents (especially in the period of their mass reproduction) and lagomorphs. The source and reservoir of the pathogen can be rats (gray and black), less commonly house mice, cats and camels.
Foci of plague occur where the source of the pathogen is a person - a patient with primary or secondary pneumonic plague, and there is a danger of infection when in contact with the corpse of the deceased from the plague (in the process of washing, burial ritual).
Carriers of the pathogen are fleas of various species. Human infection occurs in a transmissible way (when bitten by an infected flea); contact (when removing the skins from the plague-infected rodents, hares, slaughter and cutting the meat of a sick camel, in contact with household items, secretions of the patient, containing pathogens); food (by eating foods that are seeded with plague pathogens, for example, insufficiently heat-treated meat from patients with plague of camels, woodchucks). Of particular danger are patients with pulmonary plague, from which the pathogen can be transmitted by airborne droplets.
Clinical picture . The duration of the incubation period varies from several hours to 6 days, for those vaccinated - up to 10 days. There are bubonic (skin-bubonic), pulmonary and septic forms of plague.
Usually, the disease begins suddenly: there is a strong chill, headache , muscle pain and a feeling of weakness, the body temperature rises to 39 - 40 ° C. Patients are restless, fussy. The face is hyperemic, conjunctivitis is pronounced, the eyes are feverishly shining, the tongue is coated with a thick white bloom (“chalky”), swollen, and its tremor often occurs. The mucous membrane of the oral cavity is dry, the tonsils are enlarged, ulcerated. With severe illness, cyanosis is noted, an expression of suffering and horror appears on the face, its features are sharpened. Insomnia, delirium , hallucinations , agitation, slurred speech, ataxia develop. Tachycardia reaches 120 - 160 beats per minute, there are arrhythmia pulse, a sharp drop in blood pressure, shortness of breath . The liver and spleen are enlarged. Hemorrhagic or pustular lesions are often found on the skin. Sometimes on the skin at the site of penetration of the pathogen, a primary affect is formed in the form of a spot, which successively turns into a papule, a vesicle, a pustule. The pustula is sharply painful, it is soon opened, a slowly healing ulcer appears.
With the most common bubonic form, from the first day of the illness, severe pain is felt at the site of the developing bubo, which causes the patient to assume a forced position; the lymph node is palpated in the form of a small painful seal, which then increases, the surrounding fiber and skin infiltrate, merge into a dense conglomerate without a clear contour, and a plague bubo is formed. The skin in the first days is not changed, then it becomes tense, acquires a purple-bluish color, on the 6th-8th days of the disease, softening and fluctuation appear in the center of the bubo. The patient's condition improves. On the 8th-12th day of the disease, the bubo opens, thick yellowish-green pus is secreted, and a slowly scarring ulcer forms. With an unfavorable course of the disease, secondary plague pneumonia or hemorrhagic septicemia develops.
The pulmonary form of the plague is most severe and dangerous to others. It can develop primarily or secondarily as a complication of other forms. Intoxication is pronounced, there is severe chest pain, cough with bloody sputum, cyanosis , shortness of breath , tachycardia , tremor . After 2-3 days develop coma , pulmonary heart disease.
The septic form of plague by severity of flow is close to the pulmonary form, it can also be primary and secondary. In addition to severe intoxication, characterized by massive hemorrhages in the skin and mucous membranes, bleeding (gastrointestinal, pulmonary, renal, uterine). The diagnosis is made on the basis of the clinical picture, data of the epidemiological history (stay before the disease on the territory of the natural focus, contact with rodents, flea bites, etc.) and the results of laboratory studies. The greatest importance is the selection of the causative agent of plague from the material from the patient (discharge or puncture of bubo, blood, sputum, smear from the nasopharynx, etc.).
Treatment . Patients are immediately hospitalized in special hospitals. Etiotropic therapy is carried out with tetracycline preparations, streptomycin, levomycetinum, ampicillin in maximum doses for 7 to 10 days. Detoxification therapy is carried out (5% glucose solution with ascorbic acid, polyion solutions, hemodez, reopolyglucine; strophanthin, sulfocamphoain , vikasol , etc. are administered).
Prevention. Activities are conducted in two main areas: monitoring the state of natural plague foci and preventing the possible introduction of the disease from other countries. On the territory of natural foci, explanatory work is being carried out among the population on measures to prevent plague, according to epidemic indications specific prophylaxis with live vaccine is carried out.
Of particular importance in the prevention of plague is the early detection of the first cases of human diseases. If you suspect a disease, you must immediately inform the higher health authorities and quickly begin the deployment of anti-epidemic measures. The medical officer who identified the patient with suspected plague should stop receiving further patients, close doors and windows, set up a post at the premises to stop walking of patients and staff. By telephone or via the emergency department, the head doctor of the medical institution is notified, through him they request protective clothing, emergency prophylaxis (streptomycin, etc.), medicines, disinfecting solutions, and patient care items. Before the arrival of the team of consultants, the doctor provides medical aid to the patient, draws up a list of people who have communicated with the patient. People suspected of having plague are immediately isolated and hospitalized. Persons in contact with the patient, infected things, the corpse, isolated for 6 days, in contact with patients with pulmonary form of plague are placed individually, conduct medical observation with daily thermometry. Emergency chemoprophylaxis with tetracycline 0.5 g orally 3 times a day or chlorotetracycline orally 0.5 g 3 times a day for 5 days is carried out for these people, as well as the serving medical staff. All personnel serving patients work in a full anti-plague suit (pajamas or overalls, robe, hood or large scarf, cotton-gauze mask or respirator or gas mask, goggles, boots, socks, cap, rubber gloves); after the end of the work, the staff undergoes full sanitation, lives in a specially designated room and is under systematic medical supervision.
Organize monitoring of the health of the population, all identified patients with fever are hospitalized to eliminate the plague. Conduct restrictive (quarantine) measures aimed at preventing the spread of infection beyond the outbreak. In the outbreak, the current and final disinfection, disinfestation and disinsection are carried out both in the field and in the locality (if indicated).