title: Development of cross-priming amplification for direct detection of the African Swine Fever Virus, in pig and wild boar blood and sera samples.
abstract: African swine fever (ASF) is considered a major threat to the production of pigs worldwide. The ASF aetiological agent, ASFV, is the sole member of the Asfivirus genus, belonging to the Asfarviridae family. An effective ASF vaccine is not currently available, thus the only measures of ASF spread control include, reliable and fast diagnosis. Officially approved, diagnostic methods include, virus isolation, serological assays, including enzyme-linked immunosorbent assay and immunoperoxidase assay (IPT) and different modifications of the polymerase chain reaction (PCR). This paper describes the first development and application of a cross-priming amplification method (CPA) for the direct detection of genetic ASFV material, in blood and sera from pigs and wild boars. This method is specific only to ASFV DNA. The study showed that CPA had equal sensitivity, in comparison to the official, universal probe library (UPL) real-time PCR and reached 7·2 copies of standard plasmid DNA, containing a p72 gene fragment. This method was capable of detecting ASFV DNA in all examined blood samples, originating from pigs; n = 10 and wild boars; n = 76. The obtained results were also confirmed by the officially approved, real-time PCR. The developed CPA might be further used by local and county veterinary officers, hunters or pig farmers, for preliminary ASF diagnosis.
  
  
  CONCLUSIONS
  The spread of the African swine fever virus (ASFV) among infected pigs and wild boars, is currently one of the most important facets of virus transmission in eastern Europe. Cross-priming amplification (CPA) has been developed, for fast and direct development of genetic ASFV material in the blood and sera of infected pigs and wild boars. It has been shown that CPA is a rapid, sensitive and specific isothermal method for the detection of ASFV DNA, in directly collected blood or sera from pigs and wild boars.
authors.affiliation: Department of Swine Diseases, National Veterinary Research Institute (NVRI), Puławy, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Frączyk
authors.affiliation: Department of Swine Diseases, National Veterinary Research Institute (NVRI), Puławy, Poland.
authors.forename: G
authors.initials: G
authors.lastname: Woźniakowski
authors.affiliation: Department of Swine Diseases, National Veterinary Research Institute (NVRI), Puławy, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Kowalczyk
authors.affiliation: National Veterinary Research Institute (NVRI), Puławy, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Niemczuk
authors.affiliation: Department of Swine Diseases, National Veterinary Research Institute (NVRI), Puławy, Poland.
authors.forename: Z
authors.initials: Z
authors.lastname: Pejsak
mesh_terms: D000357:African Swine Fever / Q000175:diagnosis* / Q000821:virology; D000358:African Swine Fever Virus / Q000235:genetics*; D000818:Animals; D004279:DNA, Viral / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques / Q000662:veterinary*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary*; D034421:Sus scrofa / Q000821:virology*; D013552:Swine / Q000821:virology*
chemical_list: D004279:DNA, Viral
keywords: African swine fever virus; cross-priming amplification; development; direct virus DNA detection; pigs and wild boar blood; sera