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Laboratory testing is required to confirm a diagnosis of classical swine fever. As well as collection of tissues for histopathology, samples of tonsils, spleen, lymph nodes, kidney and distal ileum are taken for virus detection. Virus may be detected by fluorescent antibody detection, ''in situ'' hybridisation, PCR, immunoperoxidase staining or virus isolation. Several of these methods are reviewed by Moennig<sup>1</sup>, and are briefly summarised here.
 
Laboratory testing is required to confirm a diagnosis of classical swine fever. As well as collection of tissues for histopathology, samples of tonsils, spleen, lymph nodes, kidney and distal ileum are taken for virus detection. Virus may be detected by fluorescent antibody detection, ''in situ'' hybridisation, PCR, immunoperoxidase staining or virus isolation. Several of these methods are reviewed by Moennig<sup>1</sup>, and are briefly summarised here.
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The gold standard laboratory test for CSFV is '''virus isolation in cell culture'''. In viraemic animals, virus may be isolated both from buffy coat cells and from suspensions of spleen, lymph node, tonsil, kidney or parotid salivary glands. Samples are incubated on cultures of porcine cells, and since classical swine fever virus is non-cytopathogenic, anti-CSFV antibodies are used to detect virus. Despite good specificity and sensitivity, the virus isolation process takes around three days and is labour intensive and therefore costly. [[Immunofluorescence|'''Fluorescent antibody testing''']] is less sensitive but more rapid than virus isolation, and involves the used of fluoresecently-labelled anti-CSFV antibodies to demonstrate the presence of virus antigen in tissue. A virus antigen capture [[ELISA testing|'''ELISA''']] also established the presence of antigen through the use of specific antibodies, and is useful for screening large numbers of animals.  In the last ten years, it has become possible to detect CSF virus RNA by '''RT-PCR''', usually of the 5' untranslated region. As well as confirming infection, this allows subsequent genetic sequencing and differentiation between isolates.
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The gold standard laboratory test for CSFV is '''virus isolation in cell culture'''. In viraemic animals, virus may be isolated both from buffy coat cells and from suspensions of spleen, lymph node, tonsil, kidney or parotid salivary glands. Samples are incubated on cultures of porcine cells, and since classical swine fever virus is non-cytopathogenic, anti-CSFV antibodies are used to detect virus. Despite good specificity and sensitivity, the virus isolation process takes around three days and is labour intensive and therefore costly. [[Immunofluorescence|'''Fluorescent antibody testing''']] is less sensitive but more rapid than virus isolation, and involves the used of fluoresecently-labelled anti-CSFV antibodies to demonstrate the presence of virus antigen in tissue. A virus antigen capture [[ELISA testing|'''ELISA''']] also establishes the presence of antigen through the use of specific antibodies, and is useful for screening large numbers of animals.  In the last ten years, it has become possible to detect CSF virus RNA by '''RT-PCR''', usually of the 5' untranslated region. As well as confirming infection, this allows subsequent genetic sequencing and differentiation between isolates.
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Although antigen detection methods have largely replaced serology in the diagnosis of acute classical swine fever outbreaks, CSFV '''serology''' is important for disease surveillance, particularly in wild boar. A virus neutralisation test is the most sensitive and specific form of CSFV serology, and involved incubation of test sera with a CSFV to neutralise any anti-CSFV antibodies present. However, the virus neutralisation test takes several days, and so an ELISA test may be used when large numbers of samples must be processed.
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Although antigen detection methods have largely replaced serology in the diagnosis of acute classical swine fever outbreaks, CSFV '''serology''' is important for disease surveillance, particularly in wild boar. A virus neutralisation test is the most sensitive and specific form of CSFV serology, and involves incubation of test sera with a CSFV to neutralise any anti-CSFV antibodies present. The virus neutralisation test takes several days, and so an ELISA test may be used when large numbers of samples must be processed urgently.
    
==Treatment==  
 
==Treatment==  
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