parrot fever
Introduction
Parrot fever profile Pitttacosis, also known as ornithosis, chlamydia. It is a contact infectious disease caused by Chlamydia psittaci. Naturally, various poultry such as turkeys, chickens, pigeons, ducks, geese and wild birds can infect the disease and infect each other. It is generally called parrot fever when the parrot bird is infected and when humans come into contact with birds, and it is called bird plague, or chlamydia disease, when it occurs in various non-parrot birds. The disease is usually a recessive infection and can also have symptoms, mainly characterized by conjunctivitis, rhinitis and diarrhea. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: contact infection Complications: pneumonia myocarditis endocarditis pulmonary edema
Cause
Parrot fever
(1) Causes of the disease
Chlamydia belongs to the Chlamydia genus Chlamydia of Chlamydiales. There are four species: Chlamydia psittaci, Chlamydia pneumoniae, Chlamydia trachomatis and C. pecorum. The latter are not found in humans. Pathogenic, they are obligate intracellular parasites that can pass through a sterilizing filter. They cannot proliferate on a living cell-free medium. Instead, they acquire heat from eukaryotic cells. They have cell walls and membranes, as well as their own independent enzyme systems. The epithelial cells of the body proliferate in a two-division manner, and have a unique developmental cycle, forming inclusion bodies in the susceptible cytoplasm, negative for basophilic dyes and Gram-negative, and three kinds of Chlamydia pre-membrane masters that are pathogenic to humans. The homology of the protein gene: 71% between Chlamydia psittaci and Chlamydia pneumoniae; they are 68% between Chlamydia trachomatis, and the DNA homology of various chromosomes is less than 10%. The homology of DNA between the strains of Chlamydia psittaci in this genus model is large, still between 20% and 100%.
Recent arguments suggest that Chlamydia psittaci is a large group of heterogeneous pathogens and causes a variety of heterogeneous diseases, causing a broad spectrum of diseases in many of its natural hosts, such as enteritis, placenta, mastitis, multiple Arthritis, meningoencephalitis, pneumonia, conjunctivitis and keratoconjunctivitis, etc.
Chlamydia psittaci is Lewithai in Berlin, Coles in England and Lillie was discovered in the United States in 1930. It was once known as the LCL corpuscle. Later, Lillie was once known as the Parrot rickettsia. It has two forms of development: One is a trophoblastic reticulate body with a two-split mode of proliferation; the other is an elementary body with infectious ability, the original body is round and has a diameter of about 0.3-0.4 m. Containing the same amount of DNA and RNA, the DNA is concentrated on the electron-densified nucleus. The RNA is mainly distributed in the cytoplasmic ribose. The reticular body is about 0.5-3.0 m in diameter, and the DNA is irregularly scattered in the cytoplasm. More than three times more DNA and concentrated in the cytoplasmic ribose.
The primitive corpuscles that are free of extracellular cells enter the susceptible host cells, then combine into reticular bodies, and repeatedly proliferate in a two-splitting manner, and then polymerize into a new generation of infectious corpuscles, which are contained in the host cells. The body shape, followed by the rupture of the infected host cell, and then continuously infect the host healthy cells to complete a generational development cycle, usually takes 24 to 48 hours, sometimes or longer, their development in cell culture The process is divided into three phases, the first is the metabolic base formation period, then the synthetic DNA, the peak of RNA and protein, and finally the mature period of the infectious primordial, which can be well obtained in a variety of cell culture systems. Developmental conditions, commonly used monkey BSC-1 cells and BGMK cells, human Hela cells, KB cells and McCoy cells, as well as mouse L cells and mouse macrophages, hamster kidney cells, chicken embryo yolk sac and fibrils Cells or chorioallantoic membrane cells, etc., grow rapidly in Mc-Coy cells, and are particularly suitable for isolation and culture.
There are two kinds of different antigenic structures of genus and species specific on the cell wall of Chlamydia psittaci. The antigen is lipopolysaccharide, which is resistant to boiling and high temperature pressure of 135 °C. Deoxycholate can cause it to fall off the cell wall, high iodine and Lecithinase can also be inactivated. Chlamydia psittaci can be stored at -75 ° C or freeze-dried. It can survive in 7.5% glucose skim milk solution, sensitive to ether, can be inactivated in 30 min, 0.1% Formaldehyde or 0.5% phenol solution can be inactivated for 24h, and 25% ethanol or 40% methanol can be directly inactivated without heating. If heated at 60 °C for 10min or heated at 37 °C for 2~3h, it can lose its infectivity.
(two) pathogenesis
After invading the upper respiratory tract, the pathogens multiply in the local mononuclear macrophages and spread to the lungs and other organs through the blood. The lesions are common in the lungs and also involve the reticuloendothelial system. The pulmonary lesions are mainly lobular and interstitial pneumonia. From the hilum to the periphery, the following lungs are prominent, the alveoli have inflammatory cell infiltration and exudation, the alveolar cavity can be filled with liquid, occasionally bleeding and massive fibrin exudation, alveolar wall and interstitial tissue are thickened, edema And necrosis, liver inflammation and small focal necrosis, spleen can be swollen, pleural, heart, kidney, nervous system and digestive tract can appear lesions, in the lung macrophages, pericardium and myocardium, hepatic stellate cells can be seen Alkaline inclusion bodies.
Prevention
Parrot heat prevention
(1) Epidemic parrot fever is a disease that can be prevented by quarantine and application of tetracycline to all imported parrots.
(2) Be sure to avoid contact with infected pigeons (such as racing pigeons and homing pigeons) in the loft, other infected birds, and feather dust in the Egyptian pigeon cage. Imported parrots must be incubated with chlortetracycline for 45 days to control the spread. This method generally (not absolutely) eliminates pathogens in bird blood and feces. This measure also helps to control the spread of the disease in turkeys raised for sale. Because cough droplets and sputum can infect others by inhalation, patients should be severely isolated when they suspect the disease based on clinical and epidemiological background (contact with possible sources of infection).
(3) Prevention of parrots caused by non-parrot birds is more difficult, so it will still be a possible source of human infection. It is especially necessary to take comprehensive control measures.
Complication
Parrot fever complications Complications pneumonia myocarditis endocarditis pulmonary edema
Severe patients may have pneumonia, myocarditis, endocarditis, pulmonary edema and so on.
Symptom
Parrot fever symptoms common symptoms aversion to cold, sputum, nosebleed, congestion, nausea, rash
1. The incubation period is 5 to 21 days, the short is 3 days, and the elderly is 45 days.
2. Symptom
Sudden onset, sudden high fever of 39 ~ 40 ° C, can be accompanied by a cold and chills, a severe and diffuse headache, sustainable 7 to 10 days, often sweating more than nausea and vomiting, muscle pain, sore throat and Chest pain, etc., myalgia affects the whole body, especially the trunk and limbs. In severe cases, it is even difficult to be independent. Most patients have respiratory symptoms. Cough occurs on the 3rd to 6th day of the disease. The main cause is dry cough. The incidence of pneumonia is as high as 85%~ 90%, when the disease develops, there may be cyanosis, irritability, paralysis, coma, etc., occasionally nosebleed or rash, accompanied by slow pulse.
3. Signs
Excessive fatigue, pharyngeal congestion, weakened lung sounds or a small amount of wet snoring, severe pulmonary signs, chest X-rays showing bronchitis-type lung infiltration, the following leaves are more, or appear as Pneumonia, sometimes seen miliary lesions, liver, splenomegaly, half of the patients with abnormal liver function, occasionally rose rash and conjunctivitis.
Examine
Parrot hot check
1. The peripheral white blood cell count is normal or slightly increased or decreased. The lymphocytes are always normal and the eosinophils are reduced. Most of the patients have left nucleus or poisoned granules, and the erythrocyte sedimentation rate is accelerated.
2, acute phase patients with blood, sputum, nasopharyngeal secretions or biopsy specimens isolated pathogens, the positive rate is usually only 11% to 17%, and there is the possibility of laboratory infection, so less for diagnosis.
3. Take serum supplementation test within 2 weeks of onset and recovery period (after 6 weeks). The titer can be diagnosed by increasing the titer by more than 4 times. If the titer is above 1:16, it is also diagnostic. Indirect immunofluorescence detection specific antibody Can be used for early rapid diagnosis and epidemiological investigations.
4. Pathological and pathogenic examination of suspected birds that have been contacted as necessary to confirm the source of infection and the process of infection of the patient.
5, chest X-ray film can be seen in the bronchitis-type lung infiltration, the following leaves are more, or manifested as interstitial pneumonia, sometimes seen miliary lesions.
Diagnosis
Parrot thermal diagnosis
There is generally no difficulty in the diagnosis of outbreaks. In many specific occupational groups, it is not difficult to diagnose according to clinical manifestations and epidemiological exposure history. According to the positive results of pathogenic serology, the diagnosis can be made, but The rate of misdiagnosis in sporadic cases is as high as 80% to 100%.
The acute phase should be differentiated from febrile diseases such as typhoid, leptospirosis, brucellosis, Q fever and viral infection. Once the lungs have lesions and respiratory symptoms, they should be differentiated from bacterial pneumonia. Cough should be differentiated from chlamydia pneumonia, and severe headache should be differentiated from meningitis.
