Final answer:
Q fever is caused by Coxiella burnetii and mostly affects farm workers through inhalation of contaminated aerosols, with symptoms resembling pneumonia, which can become chronic and lead to serious complications.
Step-by-step explanation:
The disease Q fever is caused by the bacterium Coxiella burnetii. This is a highly infectious zoonotic disease, meaning it is transmitted from animals to humans. C. burnetii's primary hosts are domesticated animals like cattle, sheep, and goats. The main method of transmission to humans is through inhalation of contaminated aerosols, which makes Q fever a concern particularly for farm workers who might come into contact with infected animals or their byproducts. Symptoms of acute Q fever can include high fever, headache, coughing, pneumonia, and general malaise. Chronic Q fever is less common but can lead to serious complications such as endocarditis, which can be fatal.