Coxiella burnetii is an obligate intracellular, gram-negative bakteria and the pathogen responsible for Q-fever. It is highly infectious, even a small amount of pathogens is sufficient to establish an infection.
Coxiella burnetii is worldwide spred and has a large host range, e.g. ruminants, dogs, cats, rodents and birds as well as humans (zoonosis!). An infection in human is often subclinical but clinical non-specific severe influenza-like symptoms can be seen. Furthermore chronical forms with endocarditis, hepatitis or CNS involvement are descriebed. Affected are especially persons who are in contact with ruminants (e.g. vets, farmers, butchers).
In ruminants Coxiella burnetii replicates in the female genital tracts and in the utter. It is intermittently secreted or persistend via uterus secretion, amnion fluid and abortion material, but also via urine, faeces or milk. During replication small spore-like permanent forms are produces, which can survive very long time in the enviroment. Transmission occurs mostly by inhaling pathogenic dust, but also through direct contact with infected animals. Tick has also been found to be vectors of Coxiella burnetii, where here the tick faeces are infectious.
If clinical signs are seen in animals, they include post-natal complications, metritis, foetal death, late abortions, stillbirths with subsequent infertility or birth of weak calves.
In Germany, it is a notifiable disease in cattle, sheep, goats and other ruminants!