PCR-Based Detection of Coxiella burnetii from Clinical Samples

Q fever is caused by Coxiella burnetii , an organism widely found in nature and responsible for infections in arthropods, pets, domestic and wild animals, as well as humans (1 ,2 ). Conventional diagnosis of Q fever is mainly based on serological tests, such as immunofluorescence, enzyme-linked immunosorbent assay, and complement fixation (3 ). Isolation of C. burnetii is performed in cell culture, animals or embryonated chicken eggs, however, the procedure is time-consuming and hazardous and therefore restricted to specialized laboratories. The highly sensitive polymerase chain reaction (PCR) was shown to be a useful tool for the detection of C. burnetii-specific genomic DNA sequences in biological samples (4 –9 ). A PCR assay designated Trans-PCR, which targets a repetitive, transposon-like element (5 –8 ) proved to be specific and sensitive. However, the numerous DNA extraction steps required are time-consuming and carry a high risk of carryover contamination, thus reducing the assay’s sensitivity.