Q fever outbreak in a goat herd--diagnostic investigations and measures for control.

This is a case report about a Q fever infection of a goat herd with abortions and excretions of pathogens accompanied by human infection and disease. Following a diagnosis of Q fever in a goat herd, all animals were vaccinated with an inactivated phase 1 vaccine. The herd was kept isolated and animals were neither removed nor introduced so that monitoring of the course of the Q fever infection of the individual dam was possible. Over a period of two years following the diagnosis of a Q fever infection (abortion), diagnostic investigations on detection of Coxiella (C.) burnetii were performed using quantitative Real-Time PCR (qPCR) and for serological studies complement fixation test (CFT) and ELISA. Excretion of pathogens decreased from > 500 000 units per genital swab in the first year to < 50 units in the second year after the initial diagnosis. Serological studies of the dams using CFT revealed a dominance of phase 2 antibodies with a proportion of 35.4% (17/48) positive animals in 2006. This level decreased to a value of 2.3% (2/87) two years later. The mixed phase 1 and 2 ELISA initially yielded 20.8% (10/48) positive dams with an increase to 98.9% (86/87) two years later. The control measures which were implemented after a round table meeting are illustrated and discussed.