New methods for the detection of classical swine fever virus (CSFV) have been developed and validated. A variety of reverse transcription-polymerase chain reaction (RT-PCR) tests have been optimised and compared for ease of use and reliability, including comparisons with alternative methodologies. The methods offer advantages in terms of speed, specificity and sensitivity. Compared to previously described RT-PCR methods they are also simpler to use. For large scale usage, the tests would be best incorporated into systems for robotic sample processing.
LRT-PCR has been applied to the detection of a very wide range of pathogenic micro-organisms including CSFV. CSFV causes a very serious and notable disease of pigs whose control is subject to legislation. Correct diagnosis is of the utmost importance and prescribed methods have to be very carefully validated. As well as diagnosis of the disease in the individual animal it would be very helpful to have sensitive methods for the early detection of disease in whole pig herds. This requires large numbers of samples to be analysed in a short time. Early RT-PCR methods were un-standardised and poorly validated. They involved multiple processing steps making them prone to sample cross-contamination. This rendered them unsuited to large-scale testing and prone to give false positive results. We have simplified RT-PCR testing for CSFV by incorporating several steps into a single process. The RT and PCR steps are now carried out in the same tube, as is a hybridization reaction involving fluorescent probes. This increases the specificity, reduces the risk of false positive results and enables automated reading of results. A series of ring tests were conducted to validate the procedures.