General information
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 have been described. 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. Excretion is intermittent or persistent via uterine secretions, amniotic fluid and abortion material, but also in urine, faeces and 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, with tick faeces being particularly 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!