Ornithosis (psittacosis) is an infectious disease characterized by symptoms of intoxication, lung damage and a tendency to a protracted course with exacerbations.
The causative agent of ornithosis refers to chlamydia. It is resistant to low temperature and drying.
Birds are the source of the infectious agent. Domestic and indoor birds, parrots, pigeons, wild waterfowl, in which ornithosis is traditionally asymptomatic, have the greatest epidemiological significance. However, with a deterioration in the maintenance of poultry, a lack of food, they may show signs of the disease. Birds refuse to feed, are inactive, they have diarrhea, discharge of mucus from the nose. The disease lasts 8–9 days and ends with the death of the bird.
The main routes of transmission of the pathogen are airborne and airborne. Humans become infected by inhaling dust contaminated with the faeces and nasal mucus of diseased birds. Mostly workers of poultry farms, hunters of game birds, owners of indoor birds get sick.
The incubation period lasts within 5–30, more often 8–12 days. In some patients, malaise, nausea, and joint pain are initially noted. Usually the disease develops acutely with chills, fever; headache, pain in the muscles, joints, lower back, throat, severe weakness, insomnia, dry cough, flushing of the face and throat, redness of the sclera and conjunctiva are noted. Dryness, sore throat are possible, the voice becomes hoarse, rough, there is a feeling of tightness in the chest, soreness behind the sternum. In the most typical pneumonic form of the disease, the cough is initially dry, later with sputum, sometimes bloody. On the 4-5th day of the disease, physical signs of pneumonia, shortness of breath, and sometimes cyanosis are found. Possible pleurisy. Sometimes the disease takes a chronic course with relapses.
The diagnosis is based on epidemiological history (contact with birds), clinical picture, results of radiological and laboratory studies. Leukopenia, a sharp increase in ESR are noted in the blood.
A specific diagnostic method is an allergic intradermal test with ornithosis allergen, which is carried out from 1–5 days of illness. From serological reactions, the complement fixation reaction is used, as well as an indirect immunofluorescence reaction.
Treatment is carried out in a hospital. Antibiotics of the tetracycline series or rifampicin, anti-inflammatory and anti-allergic agents are used.
The prognosis for timely treatment is traditionally favorable. Some of the sick for a long time (over several years) have asthenia, sluggish inflammatory processes in the airways and lungs.
Prevention consists in carrying out veterinary-sanitary and medical-sanitary measures. The former include veterinary and sanitary supervision in poultry farms, zoos, and poultry plants; early detection of ornithosis in domestic and indoor birds, preventive, current and final disinfection. Gutted bird carcasses are sent to the trade network from farms that are unfavorable for ornithosis after industrial heat treatment. Eggs are also subjected to heat treatment. Down and feathers are burned. The processing of the bird will need to be done in respirators and goggles, while strictly observing the rules of personal hygiene (wash hands before eating, after work).
In the epidemic focus, current and final disinfection is carried out. For persons in contact with sick birds, medical observation is established for 2 weeks with daily thermometry, an allergic diagnostic test and a complement fixation reaction with ornithosis antigen are put. For the purpose of prevention, persons who have been in contact with sick birds should take a tetracycline antibiotic for 2-3 days. Those who have been ill are under dispensary observation for at least 1 year and are deregistered if there are no recurrences of the disease.