PLASMID BASED DIFFERENTIATION AND DETECTION OF COXIELLA-BURNETII IN CLINICAL-SAMPLES

A ''nested'' PCR approach with primers based on conserved plasmid sequ ences was used for the highly sensitive and specific detection of Coxi ella (C.) burnetii in clinical samples collected from cattle, dogs, ca ts and humans. Results were in good agreement with those obtained from Capture-ELISA and isolation of the organism in BGM cell culture. We a lso tested primers with sequences derived from genomic DNA and sequenc es based on 16S rRNA. In addition, we applied PCR for the differentiat ion of C. burnetii plasmid types from 28 isolates originating from the USA; Europe and South Africa. Reference isolates Nine Mile RSA493, Du gway 5JI08-111 and all European isolates tested were recognized only b y primers specific for the QpH1 plasmid. One isolate from a goat abort ion in Namibia reacted identically to the reference isolate Priscilla Q177 bearing the QpRS plasmid. Reference isolate S Q217 with plasmid s equences integrated into the genome reacted with none of the plasmid-s pecific primer pairs.