Volume 79, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Five strains of spotted fever group (SFG) rickettsiae previously isolated from human clinical cases and from the tick were used for molecular characterization in this study to establish their genetic relationship compared with the prototype strain Sheila Smith. Samples were tested by polymerase chain reaction (PCR) targeting the rickettsial genes , and . PCR products of the latter two genes were DNA sequenced and compared with available sequences in GenBank. The partial sequences of the five Costa Rican isolates showed 100% identity to several sequences available in GenBank, including the sequence of the virulent reference strain Sheila Smith, whereas the partial sequences of the five Costa Rican isolates showed 99.8–100% identity to sequences from GenBank. This study showed the first molecular detection of isolates from Rocky Mountain Spotted Fever patients and from the rabbit tick in different geographical zones in Costa Rica.


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  • Received : 20 Dec 2007
  • Accepted : 20 Aug 2008

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