Ornithosis (psittacosis synonym) — an acute infectious disease transmitted to man by infected birds, accompanied by phenomena of the general intoxication and lung injury.
Etiology. Exciter ornithosis hlamidozoa belongs to the group, which occupies an intermediate position between bacteria and rickettsia, on the one hand, and viruses, on the other. The causative agent is stable at normal room and low (up to -70 °) temperature drying.
Epidemiology. Psittacosis refers to a group of zoonoses with natural foci. The source of infection, birds (100 species). The main reservoir of infection, and the custodian are parrots, wild water birds (gulls, wild ducks, petrels, etc.). However, the latent, asymptomatic infection in birds in that lower body resistance (impaired content, lack of food), manifested disease progression. Diseased bird selects the agent with feces, nasal discharge, mucus from the eyes.
The main route of infection — airborne dust and airborne. Food contact and transmission are of lesser importance. Man infected by inhalation of dust contaminated with dried feces and saliva of infected birds, and dust associated with the processing of down and feathers.
The disease is more professional in nature: infected. poultry workers, hunters, owners of pet birds, including parrots.
Pathogenesis and pathology. The causative agent of psittacosis grow intracellularly, predominantly affecting retikuloendoteliya cells, lymphoid tissues and lungs. In the future, the cells are destroyed and the agent, as the products of destroyed cells into the blood, causing viremia, toxemia and allergic reorganization in the body. Against the background of these changes in the lungs usually conditionally pathogenic microbes penetrate the upper respiratory tract into the bronchi and lungs, causing a mixed viral-bacterial process. Pathogen can be trapped in cages retikuloendoteliya and then penetrate into the bloodstream, causing a relapse. In some patients, after taking a long time keep toxic residual disease, especially in the lungs, and sometimes remains of virus.
The illness observed immunological processes, including develop antibodies (komplementfiksiruyuschie, less agglutogenic and others). Immunity unstable; possible recurrence. At autopsy of the dead is celebrated catarrhal tracheobronchitis, scattered areas of atelectasis and pneumonic foci with a tendency to merge.
The clinical picture. The incubation period ranges from 6-25, usually 10-15 days. In the prodromal period that lasted 2-4 days, in some patients, there is a general weakness, fatigue, nausea, pain in the joints. Most often, the disease begins with a fever and acute temperature increase. Headache, muscle pain, joint pain, back pain, throat, severe weakness, insomnia, dry cough. Marked flushing and throat, the injection of the sclera and conjunctival vessels, tonsillitis, laryngitis and tracheobronchitis. The main manifestation of psittacosis is pathology of the respiratory system. Pneumonic effects of development to reach the 5-8th day. Clinical pneumonia is characterized by the absence of dyspnea and slight changes in the lungs, percussion and auscultation detectable. Some patients in the 5-8-day sickness against high temperature increased cough, sputum appears, dyspnea, cyanosis. In light percussion and auscultation determined brighter clinical pneumonia. The characteristic symptoms of the cardiovascular system is the lability of the pulse. In uncomplicated cases, there is bradycardia, tachycardia alternating with accession of secondary infection and during the return of the disease. Blood pressure is reduced by the maximum. The liver and spleen are usually enlarged. At the height of intoxication can be observed phenomenon meningism, but very rarely, and serous meningitis with a short and benign course. Distinguish the following variants of the disease: flu, pneumonic, typhoidal and meningeal. On the severity of the clinical course of the disease distinguish severe, moderate, light and erased form. Sometimes there are recurrent. Possible relapse early (2-4 weeks) and late (3-6 months) and chronic (2-10 years). In some patients, long-term (several years) are found in the form of residual astenovegetativnogo disorders and chronic inflammation of the airways and lungs, focal pulmonary fibrosis.
Psittacosis (from the Greek. Ornis, ornitos — bird, Synonym: psittacosis, parrot disease) — A group of zoonotic diseases that occur with a fever, and often with symptoms of interstitial SARS. Recorded in the form of single, group of diseases and epidemics among people who come into contact with the birds.
Psittacosis in a little seen in the world. Mortality in the past during outbreaks was 20 — 35%. Currently, mortality in penicillin-treated does not exceed 9.3%, and aureomitsinom Terramycin — 2.1% [Meyer (K. F. Meyer) and Eddie (V. Eddie)]. In Czechoslovakia, the mortality rate is less than 1.3% [Strauss (J. Strauss)]. In the USSR, fatalities have been observed.
Etiology. The causative agent of psittacosis is a type of Vira, class Zoovirales, family Chlamydoaceae, family Bickettsiaformis. Elementary bodies of the pathogen O. are rounded. Their size varies from 250 to 300 CMI. Causative agent in the formulations often stained with Romanovsky — Giemsa. To high temperatures and disinfectants exciter is not sustainable. Frozen at t ° -70 ° remains active for two years or more. In the dried state at various sites remain viable for several hours. Pathogen cultivated in chorion-allantois of chick embryos and in the body of white mice. Tissue culture and tumor cells for this purpose are used less frequently.
Epidemiology. The source of infection in poultry are psittacosis. Spontaneous infection is installed in more than 100 species of birds. Among them in the Soviet Union is home to over 30 species. People often become infected by contact with domestic, synanthropic birds and birds kept in cages (ducks, chickens, turkeys, pigeons, parrots, canaries, etc.). Parrot disease birds occurs in the acute and chronic form. Highly responsive to infection and especially poultry chicks die within the first day, more disease lasts 8-9 days. In birds, somnolence, tremor, lost activity due to accumulation of mucus in the respiratory organs of the bird stretches its neck and opens its beak, the eruption of the cloaca in some cases contain an admixture of blood. The acute form of the disease can be chronic. Disease, especially in adult birds may be asymptomatic. Concealed carrier birds caught in adverse conditions, often followed by clinical disease. Due to the absence of pathognomonic symptoms diagnosed psittacosis in birds placed on the basis of virological examination.
Human infection of bird occurs as a result of infection in the mouth or on the conjunctiva, the use of eggs from infected birds without heat treatment, through a break in the skin, by inhalation of infected air. Patient psittacosis man practically little dangerous to others. In the literature there are only a few reports of infection of man from man.
Among patients with OA is 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 household settings. Higher incidence among women compared with men is also conditioned by the difference in the frequency of contact with birds.
Psittacosis in humans occur as sporadic group of diseases and outbreaks. JS Bezdenezhnykh proposed to subdivide the flash on domestic, industrial and laboratory. Household outbreaks occur throughout the year. In the winter the infection occurs from pigeons and songbirds, contained in cells. In the summer, the source of infection are more likely to poultry bred in individual farms. During such outbreaks ill limited number of people. For production characteristic distinct seasonal outbreaks, which coincides with the mass cultivation and slaughter of birds. In poultry and poultry plants disease often recorded from May to August, in nurseries — in the winter and spring. Highest incidence among people involved in plucking and evisceration of carcasses of birds. Fishing flash SGHR not observed. Abroad they are timed for the season of hunting and a massive collection of eggs of wild birds. Laboratory outbreak are limited, with ill persons engaged in R infected material and care of the experimental birds and animals.
- Morbid anatomy
- The clinical course and symptoms
- Diagnosis of psittacosis
- Treatment and prevention of psittacosis