Q fever (early)

Definition:

An infectious disease which causes pneumonia, acquired from animals.

Causes, incidence, and risk factors:

Q fever is caused by the organism Coxiella burnetii. This organism primarily lives in domestic animals (cattle, sheep, and goats), cats, wild animals, and ticks.

The organism is not usually transmitted directly from animals or ticks to humans. Instead, indirect transmission of the organism occurs. Humans contract the disease after having contact with contaminated materials (materials that have been contaminated with the animal's feces, blood, placenta, etc.), after inhaling contaminated dust or droplets, or after ingestion of contaminated food or raw (unpateurized) milk.

The incubation period is 2 to 3 weeks (sometimes as short as 1 week). The disorder may range from no symptoms to moderately severe symptoms resembling influenza. If symptoms occur, they may last for several weeks.

Occupations that involve a risk for infection include slaughterhouse workers, veterinarians, researchers, food processors, and sheep and cattle workers.

This disorder is occasionally seen in children, especially those who live on a farm. It is usually found in children less than 3 years old during a work-up to discover tha cause of pneumonia.