Ornithosis
| Classification according to ICD-10 | |
|---|---|
| A70 | Chlamydia psittaci ornithosis infections |
| ICD-10 online (WHO version 2019) | |
When ornithosis or Ornithosis (also Faroe disease ) is an animal disease ( zoonosis ), which is transmitted primarily from birds to humans. This severe, flu-like general illness usually progresses with predominant involvement of the lungs ( bronchopneumonia ). Since the pathogen can be detected in parrot birds (psittacids), it is also referred to as psittacosis ( psittacosis , parrot disease ). The disease is rare in humans; In 2015 only 10 cases were reported in Germany, 5 of them in Bavaria, in 2016 there were 9 diseases, in 2017 eleven infections, in 2018 nine cases and in 2019 eleven diseases. The disease or the proof of the pathogen is notifiable in Austria and Germany in humans.
Pathogen
The pathogen is (contrary to the earlier assumption of a pneumotropic virus, Miyagawanella psittaci - cf. Lymphogranuloma venereum ) the worldwide distributed, gram-negative bacterium Chlamydophila psittaci . The pathogen is obligate intracellularly . The reservoir of this pathogen are animals ( zoonosis ), especially birds (such as parrots , pigeons , seagulls ). As is customary with reservoir hosts, the animals themselves generally show no or only a few symptoms .
transmission
The pathogen is usually absorbed by droplet infection , i.e. inhalation, by inhaling infectious fecal dust or aerosol . In this type of transmission, the upper respiratory tract is likely to be the gateway. The pathogen can also be transmitted through contact infection or smear infection , whereby almost exclusively people who are in close contact with the infectious animals are infected. In the case of extremely pathogenic (contagious) strains, transmission from person to person can occur in rare cases.
Therefore, illness in occupationally exposed people (who are particularly exposed to the pathogen) such as bird traders or workers in poultry farms can be recognized as an occupational disease .
Pathogenesis
The pathogen multiplies primarily in the respiratory epithelium of the upper respiratory tract (dry, irritable cough), after bacteremia then secondarily in the so-called reticulo-endothelial system (RES), especially in the spleen ( splenomegaly ), rarely hepatosplenomegaly (enlargement of the liver and spleen). The lungs are probably only infected secondarily via the bloodstream. Here the picture of atypical pneumonia with an increase in lymphocytes , interstitial edema of the connective tissue between the typical organ cells, rarely with necrosis of the alveolar wall and hemorrhages . The respiratory epithelium in the bronchi remains intact.
Diagnosis
Clinical picture
The diagnosis of psittacosis is usually made on the basis of the clinical picture in exposed persons. Relationships with birds in the patient's anamnesis and the x-ray of the lungs can be helpful. Normally no leukocytosis (increase in the number of leukocytes), but rather a slight leukopenia (decrease in the number of leukocytes) of about 4000–6000 / mm³ with left shift , relative lymphopenia and an increased ESR are found in the blood count .
serology
Indirect detection of the pathogen is best done on the basis of titer gradients of chlamydia- specific antibodies in the patient's serum ( complement fixation reaction , ELISA ). An exact determination of the type of chlamydia can be carried out by immunofluorescence against specific initial bodies. The culture of the pathogen is usually done only in special laboratories because of the infectivity of the pathogen and the difficult culture conditions.
Differential diagnosis
In the differential diagnosis , other pathogens that can cause atypical pneumonia come into consideration ( e.g. Legionnaires' disease , Q fever , influenza , Chlamydia pneumoniae pneumonia). Furthermore, typhoid fever , typhus fever and general sepsis excluded.
Course of disease
Gradient forms
Depending on the age and immune competence (preparedness of the immune system ) of the patient, different courses develop:
- inapparent
- Flu-like
- atypical pneumonia with sometimes severe courses
- typhoid form (rare)
Symptoms
The disease begins after an incubation period of about six to 20 days with the following symptoms:
- Body aches
- Temple and forehead headache
- Lower back pain
- Fever (39 ° C and more)
- Bradycardia (slow heart beat)
- after about five days of coughing, initially dry, irritating cough, later mucopurulent
- Splenomegaly
- rarely also myocarditis , encephalitis and hepatitis , dyspnoea
- Greenish diarrhea
In the fourth week, the fever will slowly decrease and recovery will be slow; Complete recovery and normalization of the lungs, especially after severe illnesses, only after many weeks.
If left untreated or if the fever lasts more than three weeks, however, the disease is often fatal, especially when infected with virulent strains of pathogens ( mortality 20 to 50%).
immunity
Cellular immune responses lead to immunity lasting about 30 days, after which reinfection is possible.
therapy
A medical condition must be treated by a doctor. As a rule, antibiotic therapy with tetracyclines (e.g. tetracycline, doxycycline ) or macrolides ( e.g. clarithromycin , erythromycin ) is carried out for two to three weeks.
Reporting requirement
In Germany, direct or indirect evidence of Chlamydia psittaci must be reported by name in accordance with Section 7 of the Infection Protection Act , provided the evidence indicates an acute infection. This reporting obligation for the pathogen primarily affects laboratories and their lines (cf. § 10 IfSG).
In Austria, psittacosis is notifiable in terms of suspicion, illness and death (in humans) in accordance with Section 1 (1) number 1 of the 1950 Epidemic Act . Doctors and laboratories, among others, are obliged to report this ( Section 3 Epidemics Act).
Web links
- Ornithosis - information from the Robert Koch Institute
- When the "parrot fever" went around the world
Individual evidence
- ↑ Karl Wurm, AM Walter: Infectious Diseases. In: Ludwig Heilmeyer (ed.): Textbook of internal medicine. Springer-Verlag, Berlin / Göttingen / Heidelberg 1955; 2nd edition, ibid. 1961, pp. 9-223, here: pp. 122-124 ( psittacosis ), here: p. 122.
- ^ Infection epidemiological yearbook of reportable diseases for 2015. (PDF) Robert Koch Institute , pp. 181–182; accessed November 21, 2016
- ↑ Karl Wurm, AM Walter: Infectious Diseases. 1961, p. 122.
- ↑ Psittacosis, an overview
- ↑ M. Hartung, Federal Institute for Consumer Health Protection and Veterinary Medicine (Ed.): Report on the epidemiological situation of zoonoses in Germany for 1998 (PDF) BgVV-Hefte XX / 1999 p. 18 (PDF, accessed November 21, 2016)
- ↑ Karl Wurm, AM Walter: Infectious Diseases. In: Ludwig Heilmeyer (ed.): Textbook of internal medicine. Springer-Verlag, Berlin / Göttingen / Heidelberg 1955; 2nd edition, ibid. 1961, pp. 9-223, here: p. 131.
