Abstract
Piscirickettsia salmonis is the causative agent of piscirickettsiosis, a transmissible disease of salmonid fish. Diagnosis of piscirickettsiosis has traditionally been based upon identification of typical pathological changes by histological investigation, with confirmation by immunohistochemistry on formalin‐fixed, paraffin‐embedded tissues. However, implementation of more rapid confirmatory techniques, preferably with higher levels of sensitivity and possibilities for quantification, is desirable. A real‐time polymerase chain reaction (PCR) assay was designed for specific detection of P. salmonis and tested on samples extracted from formalin‐fixed paraffin‐embedded material. Construction of a PCR‐target mimic allowed determination of detection limits, linearity of the real‐time PCR and quantitative detection of P. salmonis . The present study demonstrates the capability of the described real time PCR assay for detection of P. salmonis from paraffin‐embedded material with a high degree of sensitivity and specificity. Implementation of this assay constitutes an important development for a rapid and secure diagnosis of piscirickettsiosis.