Volume 73, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


A highly specific real-time polymerase chain reaction (PCR) assay was developed to detect spotted fever and typhus group rickettsiae using the citrate synthase gene as the target. The assay amplified rickettsial members of the spotted fever and typhus group including , , , , , , and . The ancestral group rickettsia, , did not produce a positive reaction, nor did other members of the order or any non-rickettsial bacteria. The assay had a sensitivity of one target copy number per reaction as determined by serial dilutions of a plasmid containing a spotted fever group target sequence. This quantitative assay is useful for the enumeration of rickettsiae in clinical specimens and the diagnosis of rickettsial illnesses, when rickettsial numbers are very low.


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  • Received : 14 Mar 2005
  • Accepted : 19 Aug 2005

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