Psittacosis

　　PsittacosisIt is a disease caused by the psittacosis chlamydia.. The chlamydia responsible for psittacosis belongs to the order Chlamydiales, family Chlamydiaceae, genus Chlamydia. There are four species in the genus Chlamydia: Psittacosis chlamydia, Chlamydia pneumoniae, Chlamydia trachomatis, and Chlamydia bovis and ovis. The latter has not been found to be pathogenic to humans, and the first three species, which are pathogenic to humans, are obligate intracellular parasites that can pass through sterile filters, replicate by binary fission in the host's epithelial cells, and have a unique developmental cycle. Inceptosomes are formed in susceptible cytoplasm. They are alkalineophilic and Gram-negative. They cannot proliferate on non-vital cell culture media but obtain heat energy from eukaryotic cells. There are two different antigenic structures specific to the genus and species on the cell wall of the psittacosis chlamydia.

　　During the acute infection phase of psittacosis, chlamydia can directly infect myocardial cells, leading to myocardial damage, even explosive myocarditis, and can also infect the endocardium, causing infectious endocarditis. It can also lead to heart failure due to functional defects of the endocardium. Respiratory tract infection can directly infect the lungs, leading to pneumonia, and in severe cases, can lead to severe pneumonia, acute respiratory distress syndrome, and acute pulmonary edema and other complications.

　　The incubation period of psittacosis ranges from 1 to 2 weeks, and can last up to 45 days. The clinical manifestations of psittacosis are diverse, the onset can be slow, the body temperature can gradually rise over 3 to 4 days or even longer, but it is mostly acute onset, with high fever, chills, accompanied by a relative bradycardia. There is general malaise, fatigue, and anorexia. Severe headache and general muscle pain are common complaints, pain in the limbs and trunk muscles can make the patient unable to stand, and spasms and rigidity of the muscles in the back and neck can be misdiagnosed as meningitis. Some cases have nosebleeds or rash. About 1 week later, cough, expectoration of mucus or blood-streaked sputum may occur, and in severe cases, symptoms such as dyspnea, cyanosis, restlessness, delirium, rigidity, and coma may appear. Some cases have gastrointestinal symptoms such as nausea, vomiting, and diarrhea. Jaundice indicates an adverse outcome involving the liver, with a poor prognosis.

　　To reduce the occurrence of psittacosis, first, strict quarantine should be implemented in poultry farms, bird markets, and transportation processes. Second, disinfection and quarantine supervision should be carried out in infected places and buildings. Finally, tetracycline can be mixed with feed before and after the dense transport of birds to strengthen prevention. Necessary quarantine and isolation observation measures must be taken if necessary.

　　Psittacosis, also known as bird fever, is a disease caused by Chlamydia psittaci. This disease can be diagnosed by the following tests:

　　1. peripheral blood leukocyte count is normal or slightly increased or decreased, lymphocytes are always normal, eosinophils decrease, most patients show left shift or appear toxic granules, and erythrocyte sedimentation rate accelerates.

　　2. Pathogens are isolated from the blood, sputum, nasopharyngeal secretions, or biopsy specimens of acute patients, and the positive rate is usually only 11% to 17%, and there is a possibility of laboratory infection, so it is rarely used for diagnosis.

　　3. Complement fixation tests are performed on serum taken within 2 weeks of onset and during the convalescence period (6 weeks later), and a 4-fold increase in titer can be diagnosed. If the titer is above 1:16, it also has diagnostic significance. Indirect immunofluorescence detection of specific antibodies can be used for early rapid diagnosis and epidemiological investigation.

　　4. Pathological and etiological examinations of suspected birds that have been in contact are necessary to confirm the source of infection and the process of infection in the patients.

　　5. Chest X-ray films may show lung infiltration foci of bronchitis type, more in the lower lobe, or present as interstitial pneumonia, and sometimes granulomatous consolidation foci can be seen.

　　In terms of diet and health care for psittacosis patients, it is important to avoid spicy and刺激性 foods, and more vegetables and fruits such as tomatoes, bitter melon, celery, and watermelons can be eaten. Pay attention to eating soft and easy-to-digest foods in the diet, such as rice porridge, soup, and egg custard. Gradually return to normal diet after that.

　　Patients with psittacosis should be isolated and treated to prevent transmission through the respiratory tract. The first-line drug for the pathogen is tetracycline, followed by erythromycin taken orally. Fever and symptoms can be relieved within 1-2 days of taking the medicine, and the course of treatment is about 3 weeks. Symptomatic treatment is very important, and intravenous fluid replacement should be given to those who cannot eat. Oxygen should be administered to those with difficulty breathing, and assisted respiration should be performed.