INFECTIOUS DISEASES : - etiology, pathogenesis, symptoms and course of, recognition, prediction and prevention






Etiology. The term "brucellosis" currently combined disease of animals and humans, the pathogen is a bacterial group Brucella: Br. melitensis, VG. abortus bovis and Br. abortus suis.

Epidemiology. Brucellosis belongs to the group of zoonoses; it is widely distributed outside of the originally described hearth Maltese fever (Islands and the coast of the Mediterranean sea) in all parts of the world. In the USSR there are sporadic disease, there are some endemic foci. The main reservoir of the virus is livestock (sheep, goats, cows, pigs). Less susceptible horses, donkeys, camels, deer, dogs, cats and some rodents. Diseases caused Maltese Brucella, affect mainly goats and sheep, and two other species of Brucella in accordance with their names - cows and pigs; however, the possible transfer of the pathogen to another type of animal (for example, the Maltese brutally on cows). Infected animals excrete pathogens with aborted fruits, detachable tribal ways, urine, faeces, and, most importantly, with milk. They would infect bedding material, manure, soil, grass pastures and reservoirs used for drinking water or contaminated runoff in the barnyards. Due to such a wide dispersion of infection, resistance of Brucella in the external environment and their great inviteyou ability of infecting healthy animals and humans can be quite numerous and diverse ways. Human diseases are of a professional nature (veterinarians, workers in animal husbandry, wool sorters, laboratory assistants) or occur through nutritional. Contagious is the meat and internal organs of infected animals, milk, oil (up to 25 days), curd, cheese, especially cheese (45 - 70 days). A person's susceptibility to brucellosis is very high, especially for the most pathogenic of the Maltese brutally. A sick man is obviously a danger to others, because allocates agents of the same ways as animals, but still the risk compared to last much less.

The pathogenesis. Brutally in the human body mainly penetrate through the digestive tract. When professional infections of Brucella can penetrate through the skin and mucous membranes. There is the possibility that infection of humans from each other sexually. Reproduction of the introduced pathogen occurs in the lymph system. The disease itself is in the nature of sepsis, the host acute or chronic circulation of microbes in the blood, with varying degrees of response from the reticulo-endothelial system, with the formation of secondary metastatic foci of infection and with distinct allergic reactions. The main features of the pathogenesis of brucellosis is most clearly reflected in the following scheme N. I. Ragoza:

Phase compensated infection The acute phase of sepsis without local lesions, decompensation The subacute or chronic phase of the disease with the formation of local lesions (metastases), decompensation The recovery phase compensation is incomplete (subcompensated) or full with residual effects or without them
the primary form of latent Form atroseptica   Form secondary latent
    Form septico-metastatic  
    Form secondary chronic metastatic  

Forms of primary chronic metastatic:

a) deleted;

b) clinically expressed


Thus, although for brucellosis and can be divided into specific, successive phases or cycles, but in reality, successive cyclicity of pathological processes is missing, as is typical of septic diseases. Following phase primary latency comes the phase of acute sepsis with severe temnerature reaction, the reaction from the reticulo-endotelialnah system, but usually without pronounced intoxication and local lesions. As a result of bacteremia occurs metastasis in musculoskeletal, reproductive and nervous systems. Jet phenomena in the newly formed lesions may begin before the end of the septic phase, but with the end of the last comes a long period associated with the prevalence of the symptoms listed above systems. As recovery of compensation the disease passes into the secondary latent phase, and in some cases residual effects lead the patient into a state of disability. This sequence is very often violated. Phase of sepsis may be so ambiguous clinically, that the impression of the initial development of metastatic foci, is impossible without the presence of bacteremia. The acute phase of sepsis with sufficient development of protective reactions may result in complete recovery. However, the secondary focal reactions cannot be considered only from the point of view of their metastatic origin. These lesions can be in the nature of allergic reactions (joint injury) and possibly toxic (radiculitis). Pathological characteristic obrazovanie small granulomas, histologically similar to tuberculosis tubercles, but without the cheesy decay. In the lesions, along with reactive processes, develop and regressive - hemorrhages, small necrotic nests and abscesses. In animals most characterized by loss of sexual apparatus (oophoritis, endometritis, orchitis), which can disrupt the ability to fertilize or be abortion.


Symptoms are dependent on the phase or form of the disease. Sepsis reaction temperature constant, remitting or undulipodia type with relatively good health, enlargement of the spleen and liver, joint pain and neuralgic character, leukopenia with lymph and monocytosis. In the metastatic phase: lumbosacral radiculitis, brachial plexitis, arthritis, spondylitis, bursitis, tendovaginitis, myositis, orchitis, epididymitis, women oophoritis, endometritis, abortion. The most ambiguous symptoms when erased and atypical flowing forms (see Recognition).

For. Incubation of 1 - 4 weeks, but may be delayed up to 8 weeks (the difficulty of defining the beginning of the prodromal phenomena). The diversity of the clinical course stems from the peculiarities of pathogenesis (see above). Most clearly leaking septic form, giving the temperature curve resembles the curve of recurrent typhoid fever. Diurnal temperature variations are significant (relapsing-remitting type), accompanied by moderate chills and heavy sweats. Consciousness is preserved; and the morning and afternoon hours relatively good health; the pulse is relatively slow. Gradually increase the spleen, liver and lymph nodes (often the elbow). Secondary focal reactions within the first 5 to 6 weeks is usually not observed, and sometimes the disease ends in 2 to 2 ½ months after several temperature waves. Often starting from 7 to 12 weeks of the disease, there are local lesions (see Pathogenesis )and metastatic allergic nature; obsenations phenomenon for some time still, but gradually taper off. This is the most difficult period of illness. To the previous events join exhausting the patient pain; mood oppressed duration of illness, fever, and pain. With the termination of febrile seizures local reactions persist for a long time and often leads patients to a state of disability. The total duration of the disease is delayed for months and even years. Forms occurring without the expressed septic phase, manifested by swelling and pain in joints and joints, and radicular nerve pain in women - abortion, oophoritis, mastitis. If you erased the forms of the disease are confined to local phenomena, not dostosowanie expressed in degrees, subfebrile temperature, a small increase in liver, spleen and lymph nodes; but the disease can also be delayed and robs patients of the ability to work for long term.


Raspoznavaniya on the basis of clinical symptoms is difficult due to the similarity of brucellosis with other diseases: recurrent form of typhoid fever, sepsis, malaria, tuberculosis, rheumatism and so on the Prevalence of individual symptoms, such as abdominal pain, swelling of the joints, neuralgic pain, lesions of the reproductive system, overshadow the underlying disease. Clinical symptomology not in all cases sufficiently convincing, and have to resort to laboratory studies. Even in conditions of endemic foci must be confirmed diagnosis of bacteriological (hemoculture), serological methods or medicinova breakdown.


To prevent mass human disease in the first place necessary measures to combat epidemics, especially in sheep areas: General survey of the stud, the allocation of sick animals in a particular herd quarantine for newly delivered animals, disinfection of soil and manure sheep farms, the disposal of aborted fetuses in deep holes with lime filling, the denial of access to healthy herds with brucellosis people. Milk in the affected areas must be posteritati; cooking is permitted only from pasteurized milk. Personal prevention measures: protective clothing and rubber gloves when working with animals brucellosis; washing and disinfection of hands (mercuric chloride 1 : 1 000), with the exception of the food regime boiled milk, raw vegetables and fruits. Registration of all cases of brucellosis required. Patients should be isolated. Disinfection of urine, pots, urinals and spittoons soap and carbolic solution or a 10% bleach solution. Ballooneval not allowed to work in food enterprises.