Q fever

Q fever
Immunohistochemical detection of C. burnetii in resected cardiac valve of a 60-year-old man with Q fever endocarditis, Cayenne, French Guiana: Monoclonal antibodies against C. burnetii and hematoxylin were used for staining; original magnification is ×50.
Classification and external resources
Specialty	infectious disease
ICD-10	A78
ICD-9-CM	083.0
DiseasesDB	11093
MedlinePlus	001337
eMedicine	med/1982 ped/1973
Patient UK	Q fever
MeSH	D011778
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Q fever is a disease caused by infection with Coxiella burnetii, a bacterium that affects humans and other animals. This organism is uncommon, but may be found in cattle, sheep, goats, and other domestic mammals, including cats and dogs. The infection results from inhalation of a spore-like small-cell variant, and from contact with the milk, urine, feces, vaginal mucus, or semen of infected animals. Rarely, the disease is tick-borne. The incubation period is 9–40 days. Humans are vulnerable to Q fever, and infection can result from even a few organisms. The bacterium is an obligate intracellular pathogenic parasite.

Incubation period is usually two to three weeks. The most common manifestation is flu-like symptoms with abrupt onset of fever, malaise, profuse perspiration, severe headache, muscle pain, joint pain, loss of appetite, upper respiratory problems, dry cough, pleuritic pain, chills, confusion, and gastrointestinal symptoms, such as nausea, vomiting, and diarrhea. About half of infected individuals exhibit no symptoms.

During its course, the disease can progress to an atypical pneumonia, which can result in a life-threatening acute respiratory distress syndrome, whereby such symptoms usually occur during the first four to five days of infection.

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Wikipedia