These features enable the bacteria to survive for long periods in the environment. Infection of humans usually occurs by inhalation of these organisms from air that contains airborne barnyard dust contaminated by dried placental material, birth fluids, and excreta of infected herd animals. Humans are often very susceptible to the disease and very few organisms may be required to cause infection. Only about half of all people infected with Coxiella burnetii show any signs of clinical illness. Fever usually lasts for 1 to 2 weeks.
Weight loss can occur and persist for some time.
Most patients will recover to good health within several months without any treatment. Most patients who become ill do so within 2 to 3 weeks after exposure. Q Fever is difficult to diagnose and usually requires blood tests to measure antibodies against the organism. Most patients recover to good health within several months without any treatment. However, specific antibiotics may be used to shorten the duration of the illness.