Coxiella
Diagnostic spectrum
General information
Coxiella burnetii is an obligate intracellular, gram-negative bakteria and the pathogen responsible for Q-fever. The pathogen is highly infectious, only a small amount is needed to establish an infection.
Coxiella burnetii is worldwide spred and pathogen to a wide range of species, e.g. ruminants, dogs, cats, rodents, birds and humans (zoonotic!). An infection in human is often subclinical but clinical unspecific 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 abort material, but also via urine, faeces or milk. During replication small spore-like 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 (e.g. during obstestic assistance). Tick has also been found to be vectors of Coxiella burnetii, where here the tick faeces are infectious.
As in humans the infection with Coxiella burnetii in animals is mostly subclinical. Clinical symptoms in animals are metritis, retained placenta, embryonic death, late abortions and stillborn with subsequent infertility or birth of small, weak calves..
The finding of Coxiella burnetii in cattle, sheep and goat is notifiable in most countries!