Psittacosis (synonym fever) is an acute infectious disease transmitted to humans from infected birds, accompanied by phenomena of intoxication and lung involvement.
Etiology. The causative agent of psittacosis belongs to the group of khlamidioza, occupying an intermediate position between bacteria and by Rickettsia, on the one hand, and viruses. The causative agent is stable at normal room and low (down to -70 degrees) temperature drying.
Epidemiology. Psittacosis belongs to the group of zoonoses with natural focality. The source of infection are birds (more than 100 species). The main guardian and the reservoir of infection are parrots, wild aquatic birds (gulls, wild ducks, petrels, and so on). However, latent, asymptomatic infection in birds in conditions that reduce the body's resistance (deterioration of detention, the lack of fodder), is the development of the disease. Diseased poultry excrete agent with faeces, discharge from the nose, the mucus of the eye.
The main ways of transmission is airborne dust and airborne. Contact and food routes of transmission are less important. A person infected by inhaling dust, infected dried feces and saliva of infected birds, and dust related to the processing of down and feathers.
The disease often is of a professional nature: infected. the poultry workers, hunters, owners of pet birds, including parrots.
Pathogenesis and pathological anatomy. The causative agent of psittacosis develops intracellular, primarily killing cells reticuloendothelial, lymphoid tissue and lungs. Further, the cells are destroyed and the causative agent, as the products are destroyed cells into the blood, causing wirusami, toxaemia and allergic transformation in organism. Against the background of these changes in the lungs normal conditionally pathogenic microbes upper respiratory tract penetrate into the bronchi and lungs, causing mixed viral and bacterial process. The causative agent can stay in the cells of reticuloendothelial and then again to penetrate into the blood, causing a relapse of the disease. In some patients after removal of intoxication for a long time kept the residual effects of the disease, especially in the lungs; sometimes still virusencyclo.
In the period of disease are observed and immunological processes, in particular developed antibodies (complementfixing, to a lesser extent formed agglutinin and others). Immunity unstable; re disease. The autopsy of the dead is celebrated catarrhal tracheobronchitis, scattered plots of atelectasis and pneumonic tricks with a tendency to merge.
The clinical picture. The incubation period varies 6-25, usually 10-15 days. In the prodromal period, lasting 2-4 days, in some patients, there is a General weakness, malaise, nausea, pain in the joints. Often, the disease starts acutely with chills and fever. Headache, muscle pain, joint pain, back pain, throat, severe weakness, insomnia, dry cough. There is a flushing of the face and throat, injection of scleral vessels and conjunctive, tonsillitis, laryngitis and tracheobronchitis. The main manifestation of psittacosis is a pathology on the part of the respiratory system. Pneumonic phenomena development to reach 5-8 th day. Clinically pneumonia characterized by the absence of breathlessness and small changes in the lungs identified percutere and auscultation. In some patients on 5-8th day of illness on the back of high temperature increases cough, appears sputum, dyspnea, and cyanosis. In light percutere and auscultatory determined brighter clinical picture of pneumonia. Characteristic symptom from the side of the cardiovascular system is lability pulse. In uncomplicated cases there bradycardia, changing tachycardia with the accession of secondary infection, and in the period reverse the disease. Blood pressure is reduced due to the maximum. The liver and spleen, as a rule, increased. At the height of intoxication can be observed phenomena meningism, and very rarely and serous meningitis short and favorable course. There are the following variants of the disease: flu-like, pneumonic, and typhoidal meningeal. According to severity of clinical course of the disease there are severe, moderate, mild, and the true form. Sometimes there relapsing forms. The possible recurrence of the disease early (2-4 weeks) and late (3-6 months)and chronic (2-10 years). In some patients, long-term (over several years) are residual effects in the form of asthenovegetative disorders and chronic inflammatory processes in the respiratory tract and lungs, bronchial of pneumosclerosis.
Ornitz (from the Greek. ornis, ornitos - bird; synonym: fever, parrot disease - diseases of the group of zoonotic diseases, which are accompanied with fever and often with symptoms of atypical interstitial pneumonia. Register in the form of single, group of diseases and outbreaks among men who have contact with birds.
Ornitz in small numbers are observed in different countries of the world. Mortality in the past during outbreaks reached 20 - 35%. Currently, the case fatality rate among treated with penicillin does not exceed 9.3 percent, aureomycin and terramycin - 2,1% [Meyer (K. F. Meyer) and Eddie (Century Eddie)]. In Czechoslovakia the mortality rate does not exceed 1.3% [Strauss (J. Strauss)]. In the USSR lethal cases were observed.
Etiology. The causative agent of ornithosis refers to the type of Vira, class Zoovirales, family Chlamydoaceae, kind Bickettsiaformis. Elementary bodies of the pathogen O. are rounded. Their size varies from 250 to 300 MMK. The causative agent in the drugs most often paint Romanovsky - Giemsa. To high temperatures and disinfectants pathogen is not sustainable. Frozen at the temperature of -70° remains active for 2 years and more. In the dried state on various objects remain viable for several hours. The causative agent is cultivated on the chorion-allantois chicken embryo and in the body of white mice. Culture of tissue and tumor cells are used less frequently.
Epidemiology. The source of infection when ornitsa are birds. Spontaneous infection installed more than 100 species of birds. Among them on the USSR territory is home to over 30 species. People often infected by contact with home, synanthropic birds and bird contained in the cells (ducks, chickens, turkeys, pigeons, parrots, Canaries and others). Psittacosis in birds occurs in acute and chronic form. Vazokonstrikciei to infection of poultry and especially juveniles die within the first day, more often, the disease lasts 8-9 days. Birds appear drowsiness, shaking, lost activity, due to the accumulation of mucus in the respiratory bird cranes and reveals the bill, the eruption of the cesspit, in some cases, contain a mixture of blood. The acute form of the disease may take a chronic course. The disease, especially in adult birds, may be asymptomatic. Hidden carriage of birds caught in adverse conditions, often followed clinically apparent disease. Due to the lack of pathognomonic symptoms diagnosis of psittacosis in birds is based on the results of virological tests.
Human infection from birds is the result of infection in the mouth or on the conjunctiva of the eye, use eggs from infected birds without heat treatment, through damaged skin, by inhalation of infected air. Patient psittacosis people practically little dangerous to others. In the literature there are only a few reports of human infection from a person.
Among patients O. dominated by people in middle and old age. Rare cases of disease among children due to their limited contact with birds in poultry farms and in daily life. Higher incidence among women compared with men is caused also by the difference in the frequency of contact with birds.
Ornitz people occur as sporadic, group of diseases and outbreaks. I. S. Bezdenezhnykh proposed to subdivide the flash on domestic, industrial and laboratory. Household outbreaks occur throughout the year. In the cold period the infection occurs from doves and songbirds contained in the cells. In summer, the source of infection are often poultry bred in individual households. During these outbreaks ill limited number of people. For the production of outbreaks are characterized by a pronounced seasonality, coinciding with the mass rearing and slaughtering birds. At poultry farms and ptitsekombinatov diseases are registered more often from may to August; in nurseries - in winter and spring time. The highest morbidity among people engaged in plucking and evisceration birds. Commercial outbreaks in SGHR was not observed. Abroad they are timed to the hunting season and mass collection of eggs of wild birds. Laboratory outbreaks have limited; ill persons engaged in the study of infected material and care of experimental birds and animals.
