title: Relative sensitivity of conventional and real-time PCR assays for detection of SFG Rickettsia in blood and tissue samples from laboratory animals.
abstract: Studies on the natural transmission cycles of zoonotic pathogens and the reservoir competence of vertebrate hosts require methods for reliable diagnosis of infection in wild and laboratory animals. Several PCR-based applications have been developed for detection of infections caused by Spotted Fever group Rickettsia spp. in a variety of animal tissues. These assays are being widely used by researchers, but they differ in their sensitivity and reliability. We compared the sensitivity of five previously published conventional PCR assays and one SYBR green-based real-time PCR assay for the detection of rickettsial DNA in blood and tissue samples from Rickettsia- infected laboratory animals (n = 87). The real-time PCR, which detected rickettsial DNA in 37.9% of samples, was the most sensitive. The next best were the semi-nested ompA assay and rpoB conventional PCR, which detected as positive 18.4% and 14.9% samples respectively. Conventional assays targeting ompB, gltA and hrtA genes have been the least sensitive. Therefore, we recommend the SYBR green-based real-time PCR as a tool for the detection of rickettsial DNA in animal samples due to its higher sensitivity when compared to more traditional assays.
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Galina E
authors.initials: GE
authors.lastname: Zemtsova
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Merrill
authors.initials: M
authors.lastname: Montgomery
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Levin
mesh_terms: D000818:Animals; D000830:Animals, Laboratory / Q000382:microbiology; D001907:Boutonneuse Fever / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology / Q000662:veterinary*; D004269:DNA, Bacterial / Q000032:analysis; D005456:Fluorescent Dyes / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods*; D012281:Rickettsia / Q000235:genetics / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D012867:Skin / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D005456:Fluorescent Dyes