Objective: We investigated the advantages and disadvantages of six methods to detect classical swine fever virus (CSFV).
Methods: We used six methods, including the virus isolation, colloidal gold immunochromatographic assay (CGIA), antigen-capture ELISA (AC-ELISA), reverse transcription-polymerase chain reaction (RT-PCR), TaqMan real-time RT-PCR (RT-qPCR) and reverse transcription-loop-mediated isothermal amplification assay (RT-LAMP), to detect CSFV in 50 samples parallelly.
Results: The results showed that 13 samples were detected positive by RT-qPCR and RT-LAMP, 11 by PCR, 10 by virus isolation, 9 by AC-ELISA and 8 by CGIA, and 8 samples were detected positive and 37 samples negative by the six methods.
Conclusion: These results indicated that the 3 RNA-amplification assays could be used as the first choice for detection of CSFV due to the high sensitivity, while they were vulnerable to false positive results arising from sample to sample contaminations or from other contaminated sources. Although the virus isolation was time-consuming, it was still considered the "gold standard" and was indispensable for confirming CSF outbreaks. The rest two methods, AC-ELISA and CGIA, yielded the results in a short time yet their performance was hampered by a low sensitivity. Therefore, they were mainly used for herd diagnosis and not suitable for individual test for CSFV infection.