Abstract: Nucleic acid detection is the main method to diagnose the infection of classical swine fever virus (CSFV). To monitor performance and compare the measuring results of CSFV nucleic acid obtained by different laboratories, Certification and Accreditation of the People's Republic of China organized the national proficiency testing program “Diagnostic Techniques for Classical Swine Fever” (CNCA-19-A01). This program was undertaken by National/OIE Reference Laboratory for Classical Swine Fever (NRLCSF) which is affiliated to China Institute of Veterinary Drug Control. Positive and negative samples were prepared and numbered randomly. Four samples were sent to each participant and measured according to the participant's instruction. All participants should submit the qualitative results and the original reports to NRLCSF. If the results are not in line with expectation, the participant would have another chance to retest. If the result was still incorrect, the participant would be considered unqualified to detect CSFV nucleic acid. Ninety-seven institutions have participated this program. The accurate rate is 93.81% for the first test, and 98.97% for the first and second tests. This program shows that over 90% institutions have the capability for CSFV nucleic acid detection. These institutions could provide correct results and meet the requirements for CSF diagnosis and surveillance. For the unqualified institutions, the program could help them to investigate the reason for disagreement and implement their deficiencies.

Key words: classical swine fever virus, nucleic acid detection, proficiency testing