Edit concept Create issue ticket

Psittacosis

Ornithosis

Psittacosis is a contagious animal disease bearing the capability of transmission to humans and caused as a result of a Chlamydia psittaci infection. Humans can be infected from parrots, pigeons, ducks, hens, and many other bird species.


Presentation

The incubation period for psittacosis is 1 to 4 weeks. The majority of infections cause symptoms in 5 to 14 days.

Symptoms

Signs

Psittacosis often causes cardiac involvement, including bradycardia, pericarditis, endocarditis or myocarditis. Signs of pneumonic consolidation may arise, although a chest examination does not produce any characteristic results. Chest x-ray can also unveil the degree of pulmonary involvement. A less common feature observable by a physical examination is splenomegaly, which, if accompanied by  pneumonia, makes the diagnosis of psittacosis more likely. Dermatological signs include Horder's spots, erythema nodosum, or erythema multiforme.

Splenomegaly
  • Diagnosis can be suspected in case of respiratory infection associated with splenomegaly and/or epistaxis. Headache can be so severe that it suggests meningitis and some nuchal rigidity is not unusual.[en.wikipedia.org]
  • Boala poate evolua uneori ca o reticuloza maligna cu febra, stare septica, splenomegalie, ulceratii bucale, sindrom hemoragie sau ca o agranulocitoza.[esanatos.com]
Cough
  • Headache (96% of patients), chills (93% of patients), and fever (89% of patients) were the most common symptoms; a nonproductive cough occurred in 65% of patients.[ncbi.nlm.nih.gov]
  • The main symptoms are intense headache, chills and fever and an irritating non-productive cough. Later most patients develop signs of pneumonitis most clearly seen on radiographic examination.[ncbi.nlm.nih.gov]
  • Patients typically present with 1 week of fevers, headache, myalgias, and a nonproductive cough. Although pneumonia is the most common manifestation, all organ systems can be involved.[ncbi.nlm.nih.gov]
  • Psittacosis was a well-defined illness that was characterized by an abrupt onset of fever, rigors, sweats, and prominent headache, and a mild dry cough which appeared late frequently. However, respiratory symptoms were absent in 18% of patients.[ncbi.nlm.nih.gov]
  • Psittacosis causes a wide range of symptoms, including fever, headache, and a dry cough. This illness can also cause pneumonia (a lung infection) that may require treatment or care in a hospital. Rarely, psittacosis can be deadly.[cdc.gov]
Dry Cough
  • Psittacosis was a well-defined illness that was characterized by an abrupt onset of fever, rigors, sweats, and prominent headache, and a mild dry cough which appeared late frequently. However, respiratory symptoms were absent in 18% of patients.[ncbi.nlm.nih.gov]
  • Psittacosis causes a wide range of symptoms, including fever, headache, and a dry cough. This illness can also cause pneumonia (a lung infection) that may require treatment or care in a hospital. Rarely, psittacosis can be deadly.[cdc.gov]
Pharyngitis
  • On the suspicion of psittacosis, pharyngeal swabs from the couple were taken and sent to the Belgian reference laboratory for psittacosis.[ncbi.nlm.nih.gov]
Dyspnea
  • The second week is more akin to acute bacteremic pneumococcal pneumonia with continuous high fevers, headaches, cough, and dyspnea . X-rays show patchy infiltrates or a diffuse whiteout of lung fields.[en.wikipedia.org]
Fever
  • Patients usually provisionally diagnosed as having typhoid fever or pneumonia are regularly admitted to the Rietfontein Fever Hospital suffering from psittacosis.[ncbi.nlm.nih.gov]
  • However, relapse can occur, and treatment must continue for at least 10–14 days after fever subsides.[en.wikipedia.org]
  • This compendium provides information on AC (also known as psittacosis, ornithosis, and parrot fever) and psittacosis (also known as parrot disease, parrot fever, and chlamydiosis) to public health officials, veterinarians, physicians, the companion-bird[ncbi.nlm.nih.gov]
  • Even if respiratory symptoms are minimal, psittacosis and other atypical pneumonias should be considered in any patient presenting with fever and cerebellar involvement.[ncbi.nlm.nih.gov]
  • Psittacosis is a systemic disease that causes fever, headache and pneumonia. Although potentially serious, it is rarely fatal unless respiratory or renal failure occurs.[ncbi.nlm.nih.gov]
Veterinarian
  • Here we describe an epidemiological investigation conducted by physicians and veterinarians after a reported case of psittacosis.[ncbi.nlm.nih.gov]
  • This compendium provides information on AC (also known as psittacosis, ornithosis, and parrot fever) and psittacosis (also known as parrot disease, parrot fever, and chlamydiosis) to public health officials, veterinarians, physicians, the companion-bird[ncbi.nlm.nih.gov]
  • This compendium provides information about psittacosis and AC to public health officials, physicians, veterinarians, the pet bird industry, and others concerned about controlling these diseases and protecting public health.[ncbi.nlm.nih.gov]
  • This compendium provides information about psittacosis and AC to public health officials, physicians, veterinarians, members of the pet bird industry, and others concerned about controlling these diseases and protecting public health.[ncbi.nlm.nih.gov]
  • This compendium provides information about psittacosis and avian chlamydiosis to public health officials, physicians, veterinarians, the pet bird industry, and others concerned with controlling these diseases and protecting public health.[ncbi.nlm.nih.gov]
High Fever
  • The second week is more akin to acute bacteremic pneumococcal pneumonia with continuous high fevers, headaches, cough, and dyspnea . X-rays show patchy infiltrates or a diffuse whiteout of lung fields.[en.wikipedia.org]
Rigor
  • Psittacosis was a well-defined illness that was characterized by an abrupt onset of fever, rigors, sweats, and prominent headache, and a mild dry cough which appeared late frequently. However, respiratory symptoms were absent in 18% of patients.[ncbi.nlm.nih.gov]
  • Laboratory suggestive evidence Detection of IgM or single high IgG antibody titre 2 to C. psittaci by MIF OR A single high C. psittaci CF antibody titre. 2 Clinical evidence Pneumonia OR AT LEAST TWO of the following: fever, headache, myalgia, rigors,[health.gov.au]
Chills
  • Headache (96% of patients), chills (93% of patients), and fever (89% of patients) were the most common symptoms; a nonproductive cough occurred in 65% of patients.[ncbi.nlm.nih.gov]
  • The main symptoms are intense headache, chills and fever and an irritating non-productive cough. Later most patients develop signs of pneumonitis most clearly seen on radiographic examination.[ncbi.nlm.nih.gov]
Diarrhea
  • […] psit·ta·co·sis \ ˌsi-tə-ˈkō-səs \ Definition of psittacosis : an infectious disease of birds caused by a bacterium ( Chlamydia psittaci synonym Chlamydophila psittaci ), marked by diarrhea and wasting, and transmissible to humans in whom it occurs as[merriam-webster.com]
  • In the first week of psittacosis the symptoms mimic typhoid fever : prostrating high fevers , joint pains , diarrhea , conjunctivitis , nose bleeds and low level of white blood cells in the blood. [2] Rose spots can appear and these are called Horder's[en.wikipedia.org]
Abdominal Pain
  • We report the case of a psittacosis patient with severe abdominal pain who subsequently developed acute respiratory failure. The main symptoms of psittacosis are considered to be upper respiratory inflammation and influenza-like symptoms.[ncbi.nlm.nih.gov]
Hepatomegaly
  • Mononucleoza infectioasa Febra romi tenta sau ondulanta in forma clinica comuna nu ridica probleme de diagnostic, fiind insotita de angina, limfadenopatie cu neralizare rapida, splenomegalie, hepatomegalie, leucocitoza cu mono-nucleare aii pice in proportie[esanatos.com]
Myalgia
  • Patients typically present with 1 week of fevers, headache, myalgias, and a nonproductive cough. Although pneumonia is the most common manifestation, all organ systems can be involved.[ncbi.nlm.nih.gov]
  • Laboratory suggestive evidence Detection of IgM or single high IgG antibody titre 2 to C. psittaci by MIF OR A single high C. psittaci CF antibody titre. 2 Clinical evidence Pneumonia OR AT LEAST TWO of the following: fever, headache, myalgia, rigors,[health.gov.au]
Epistaxis
  • Diagnosis can be suspected in case of respiratory infection associated with splenomegaly and/or epistaxis. Headache can be so severe that it suggests meningitis and some nuchal rigidity is not unusual.[en.wikipedia.org]
  • Debutul este adesea insidios, cu febra, uneori de aspect difazie, cu simptome discrete (epistaxis, mialgii, fenomene catarale respiratorii, tuse uscata, cefalee, dureri toracice, astenie).[esanatos.com]
Headache
  • Psittacosis is a systemic disease that causes fever, headache and pneumonia. Although potentially serious, it is rarely fatal unless respiratory or renal failure occurs.[ncbi.nlm.nih.gov]
  • Each of the patients had pulmonary infiltrates, prominent headache, abdominal complaints, and serologic evidence for infection with Chlamydia psittaci.[ncbi.nlm.nih.gov]
  • However, during pregnancy, this disease may present with severe headache, hypoxemia, thrombocytopenia, anemia, hepatic dysfunction, and disseminated intravascular coagulation.[ncbi.nlm.nih.gov]
  • Headache (96% of patients), chills (93% of patients), and fever (89% of patients) were the most common symptoms; a nonproductive cough occurred in 65% of patients.[ncbi.nlm.nih.gov]
  • The main symptoms are intense headache, chills and fever and an irritating non-productive cough. Later most patients develop signs of pneumonitis most clearly seen on radiographic examination.[ncbi.nlm.nih.gov]
Confusion
  • He was febrile but not confused, and he responded rapidly to treatment with erythromycin.[ncbi.nlm.nih.gov]

Workup

A detailed medical history is vital for the direction of diagnostic tests towards a possible C. psittaci infection. Should the symptoms resemble those of psittacosis, a physician has to inquire about possible contact to birds, such as canaries and parrots, or other mammals. In many occasions, pets or domesticated birds and animals that are infected with the bacterium can simultaneously transmit it to the whole family; therefore, a family history of symptoms similar to the patients' should also raise suspicion of a potential psittacosis case.

A thorough physical exam should also be conducted in order to establish the existence of typical findings: fever, pharyngeal erythema, diffuse rales, hepatomegaly, splenomegaly and potentially, tachycardia [1], are all compatible with a respiratory psittacosis. More specifically, an erythema of the sclera is usually the one and only finding in cases of psittacosis strictly confined to the eye [11].

Blood tests are also useful in detecting markers of mild inflammation and serological markers. The white blood cell count will most likely be found normal or augmented with a left shift and sometimes eosinophilia is present. Liver enzymes are normal or slightly elevated. As far as serology is concerned, microimmunofluorescence (MIF) antibody is used to detect a C. psittaci infection. Cultured pleural fluid, sputum or blood may also produce a positive result, but the procedure should not be attempted by professionals without much clinical experience, since there is a significant danger of creating aerosolized particles and contaminating the laboratory grounds. Regarding imaging techniques, a chest x-ray may unveil the presence of cellular exudate in the pulmonary alveoli, a typical finding of pneumonia [1].

Sputum tested by means of a polymerase chain reaction (PCR) is a relatively new test for detecting a C. psittaci infection. Its use is currently limited and has primarily been applied to unveil the presence of C. psittaci in tissue harvested from animals [12].

Pulmonary Infiltrate
  • Pulmonary infiltrates that persist or are refractory to usual therapy can be a clue to this diagnosis. An outbreak or cluster of cases may occur if there is a common source of the bacterium.[ncbi.nlm.nih.gov]
  • Each of the patients had pulmonary infiltrates, prominent headache, abdominal complaints, and serologic evidence for infection with Chlamydia psittaci.[ncbi.nlm.nih.gov]
Chlamydia
  • A case of Chlamydia B (psittacosis) endocarditis is described in a patient with no known previous valve disease. After mitral valve replacement a fall in Chlamydia B antibody titre occurred.[ncbi.nlm.nih.gov]
  • Throat cultures for Chlamydia psittaci and serological tests for Chlamydia species, including strain TWAR, were obtained from 37 people.[ncbi.nlm.nih.gov]
  • Chlamydia psittacae is endemic among New Zealand birds. The difficulties of diagnosis are discussed.[ncbi.nlm.nih.gov]
  • Culture and nested polymerase chain reaction (PCR) tests were positive for the presence of Chlamydia psittaci, and ompA genotyping indicated genotype A in both patients.[ncbi.nlm.nih.gov]
  • A patient had severe pneumonia, respiratory failure, and disseminated intravascular coagulation caused by Chlamydia psittaci.[ncbi.nlm.nih.gov]
Complement Fixing Antibody
  • In the subsequent investigation of this problem, human psittacosis was defined as a fourfold rise in complement-fixing antibody titer to or 32 or a single titer of or 32 in a patient with fever and/or respiratory symptoms.[ncbi.nlm.nih.gov]

Treatment

First-line treatment of psittacosis includes tetracycline or doxycycline for 2-3 weeks to prevent the potential relapse [6]. In cases where the aforementioned treatment is not indicated, erythromycin may alternatively be administered. ICU or high-dependency treatment may be a necessity for patients with severe coexisting pathologies.

Prognosis

Patients with a C. psittaci infection greatly benefit from a therapeutic scheme including antibiotic agents. Symptoms usually subside within 24 hours, even though symptomatology can re-emerge in cases of persistent infection [1].

Patients with severe symptomatology are in risk of succumbing to potentially fatal complications, such as pulmonary and cardiac incidents [1], should proper IV drugs not be administered promptly. Antibiotic resistance has been reported by non-scientific data and concerns azithromycin [10].
Mortality can amount up to 20% in patients who do not receive any treatment [1].

Etiology

Psittacosis is a result of an infection with chlamydia psittaci and is a disease known to the medical community for over a century [3]. People can contract the bacterium from direct contact with poultry, birds, mammals, or their secretions, excrement and tissue. Therefore, individuals whose profession involves close contact to potentially infected animals do run a higher risk of contracting C. psittaci [4]. Bacterial transmission from one person to another is a rare observation [5] [6].

Epidemiology

Psittacosis' frequency has followed declining pattern, as far as the industrialized world is concerned, although it can be observed in any part of the world. Data indicates that from 1988 to 2003, the Center for Disease Control and Prevention (CDC) recorded 935 reports of psittacosis; the average incidence of the disease was 62 cases per year [7]. However, in the time period 2005 to 2009, only 66 additional cases reached the CDC, and so, averagely 16 human cases per year were recorded [8]. It is, however, believed, that in reality, the number of psittacosis-affected patients was larger and remained undiagnosed because the condition responds well to antibiotics administered empirically for cases of pneumonia.

Mortality rate used to amount to a staggering 15-20% in the past, due to lack of appropriate treatment. With the advent of antibiotics, the numbers have decreased to 1%. Psittacosis can affect people of all ages, ethnicities and genders. A slight increase of the number of people who contract C. psittaci in the industrialized world may be explained by the importation of exotic birds to these countries.

Psittacosis can affect all people irrespective of age, but is usually observed amongst people in their middle decades.

Sex distribution
Age distribution

Pathophysiology

C. psittaci has a specific two-phased developmental cycle, featuring the contagious elementary body form (EB) and the reticulate body form (RB). While in the EB form, the bacterium latches on to the host cell and is endophagocytosed. It is then surrounded by an inclusion body, which assists the bacterium in its survival, as the lysosomes are unable to penetrate the structure. The EB then transforms into a replicating RB and produces the so-called intermediate bodies, where chromatin subsequently follows a condensation process, transforming into an EB. Cell lysis or exocytosis are the procedures responsible for EB's release from its host; the cell sustains no damage itself and the newly-produced EBs can further infect other cells in the vicinity, something which is expected to happen 36-48 hours after contagion [1]. 

C. psittaci can be cultured in various substrates, but protective measures and caution are advised, for fear of producing aerosolized particles. Aerosolized particles and contact with excrement, nasal secretions, or tissue are the ways a human can get infected. 7 known C. psittaci genotypes have been identified, all of which can be contracted by humans [9]. The length of its maturation cycle and its endurance are the factors that probably result in chronic infection, which cannot be eradicated with the usual antimicrobial medication. There are also bacterial types that are deemed more lethal. For a treatment scheme to be successful, a longer period of antibiotic administration is necessary; even in these cases, some patients may still have sustained difficult-to-eradicate infection.

Prevention

One of the first measures one can take to prevent psittacosis is making sure that pet birds will not contract it themselves. Measures include: cleaning birdcages daily, taking good care of pet birds to prevent an infection, proper food and enough space, so they are not always close to one another in the cage. If there are more cages with birds, keeping the cages at a distance will prevent excrement and other biological substances from being transferred from one cage to another.

Any new bird expected to join the cage should be kept at separate surroundings and monitored for at least 30 days, before it can be placed together with other birds.

Summary

Psittacosis is an infectious disease caused by Chlamydia psittaci, an obligate, intracellular, gram-negative bacterium [1]. The primary hosts of C. psittaci are birds and mammals, with humans being only accidental hosts [1]. Humans can get infected irrespective of age; contracting the bacterium results in conjunctivitis and community-acquired pneumonia [1] [2]. Psittacosis also goes by the names parrot fever and ornithosis, and is sometimes reserved for the disease when it is carried by birds of the Psittacidae family; ornithosis is used when other birds are the disease carriers.

Patient Information

Psittacosis is a contagious disease caused by Chlamydophila psittaci. It is a type of organism (bacterium), which infects birds and mammals and can infect humans who come into contact with their excrement and secretions. People who run a higher risk for contracting C. psittaci are those who have direct contact to animals: veterinarians, bird owners, pet shop employees. The birds that are most frequently infected are parrots, parakeets, and budgerigars, although other birds and animals can also be affected by the disease and transmit it to humans. Typical symptoms include fever, chills, head and muscle aches, blood in one's sputum and malaise.

In order to diagnose the disease, a physician will carry out a detailed physical examination and will also ask for a detailed medical history. Other laboratory tests on sputum and blood, a chest CT scan or x-ray can also contribute to the successful diagnosis of a psittacosis infection. Patients are treated with antibiotics upon the diagnosis and are expected to have a full recovery, if they have no other diseases.

In order to prevent the disease, avoid exposure to birds that you suspect to be ill, such as imported parrots or unknown birds. Take good care of other conditions you might be affected by, so that your immune system is as strong as possible against all types of infection.

References

Article

  1. Schlossberg D. Chlamydophila (chlamydia) psittaci (psittacosis). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and practice of infectious diseases, 6th ed. Philadelphia, PA: Churchill Livingston; 2005:2256-2258.
  2. Dean D, Kandel RP, Adhikari HK, et al. Multiple Chlamydiaceae species in trachoma: implications for disease pathogenesis and control. PLoS Med. 2008;5:e14.
  3. Harris RL, Williams TW Jr. "Contribution to the question of pneumotyphus": a discussion of the original article by J. Ritter in 1880. Rev Infect Dis. 1985;7:119-122.
  4. Gaede W, Reckling KF, Dresenkamp B, et al. Chlamydia psittaci infections in humans during an outbreak of psittacosis from poultry in Germany. Zoonoses Public Health. 2008;55:184-188.
  5. Harkinezhad T, Geens T, Vanrompay D. Chlamydia psittaci infections in birds: a review with emphasis on zoonotic consequences. Vet Microbiol. 2009;135:68-77.
  6. Ito I, Ishida T, Mishima M, et al. Familial cases of psittacosis: possible person-to-person transmission. Intern Med. 2002;41:580-583.
  7. Smith KA, Bradley KK, Stobierski MG, et al. Compendium of measures to control Chlamydophila psittaci (formerly Chlamydia psittaci) infection among humans (psittacosis) and pet birds, 2005. J Am Vet Med Assoc. 2005 Feb 15. 226(4):532-9.
  8. Smith KA, Campbell CT, Murphy J, et al. Compendium of measures to control Chlamydophila psittaci infection among humans (psittacosis) and pet birds (avian chlamydiosis), 2010. J Exotic Pet Med. 2011 Jan. 20 (1):32-45.
  9. Vanrompay D, Harkinezhad T, van de Walle M, et al. Chlamydia psittaci transmission from pet birds to humans. Emerg Infect Dis. 2007;13:1108-1110.
  10. Binet R, Maurelli AT. Frequency of development and associated physiological cost of azithromycin resistance in Chlamydia psittaci 6BC and C. trachomatis L2. Antimicrob Agents Chemother. 2007;51:4267-4275.
  11. Dean D. Pathogenesis of chlamydial ocular infections. In: Tasman W, Jaeger EA, eds. Duane's foundations of clinical ophthalmology. Philadelphia, PA. Lippincott Williams & Wilkins, 2010.
  12. Sprague LD, Schubert E, Hotzel H, et al. The detection of Chlamydophila psittaci genotype C infection in dogs. Vet J. 2009;181:274-279.

Ask Question

5000 Characters left Format the text using: # Heading, **bold**, _italic_. HTML code is not allowed.
By publishing this question you agree to the TOS and Privacy policy.
• Use a precise title for your question.
• Ask a specific question and provide age, sex, symptoms, type and duration of treatment.
• Respect your own and other people's privacy, never post full names or contact information.
• Inappropriate questions will be deleted.
• In urgent cases contact a physician, visit a hospital or call an emergency service!
Last updated: 2017-08-09 17:42