title: Genetic Characterization of Circulating African Swine Fever Viruses in Nigeria (2007-2015).
abstract: Sequencing and analysis of three discrete genome regions of African swine fever viruses (ASFV) from archival samples collected in 2007-2011 and active and passive surveillance between 2012 and 2015 in Nigeria were carried out. Analysis was conducted by genotyping of three single-copy African swine fever (ASF) genes. The E183L and B646L genes that encode structural proteins p54 and p72, respectively, were utilized to delineate genotypes before intragenotypic resolution by characterization of the tetrameric amino acid repeat region within the hypervariable central variable region of the B602L gene. The results showed no variation in the p72 and p54 gene regions sequenced. Phylogeny of p72 sequences revealed that all the Nigerian isolates belonged to genotype I, while that of the p54 recovered the Ia genotype. Analysis of B602L gene revealed the differences in the number of tetrameric repeats. Four new variants (Tet-15, Tet-17a, Tet-17b and Tet-48) were recovered, while a fifth variant (Tet-20) was the most widely distributed in the country displacing Tet-36 reported previously in 2003-2006. The viruses responsible for ASF outbreaks in Nigeria are from very closely related but mutated variants of the virus that have been circulating since 1997. A practical implication of the genetic variability of the Nigerian viral isolates in this study is the need for continuous sampling and analysis of circulating viruses, which will provide epidemiological information on the evolution of ASFV in the field versus new incursion for informed strategic control of the disease in the country.
authors.affiliation: Applied Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria.|College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.
authors.forename: P D
authors.initials: PD
authors.lastname: Luka
authors.affiliation: Animal Production and Health Laboratory of the Joint IAEA/FAO Division, Vienna, Austria.
authors.forename: J E
authors.initials: JE
authors.lastname: Achenbach
authors.affiliation: College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.
authors.forename: F N
authors.initials: FN
authors.lastname: Mwiine
authors.affiliation: Animal Production and Health Laboratory of the Joint IAEA/FAO Division, Vienna, Austria.
authors.forename: C E
authors.initials: CE
authors.lastname: Lamien
authors.affiliation: Research Directorate, National Veterinary Research Institute, Vom, Nigeria.
authors.forename: D
authors.initials: D
authors.lastname: Shamaki
authors.affiliation: Animal Production and Health Laboratory of the Joint IAEA/FAO Division, Vienna, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Unger
authors.affiliation: College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.
authors.forename: J
authors.initials: J
authors.lastname: Erume
mesh_terms: D000357:African Swine Fever / Q000453:epidemiology* / Q000821:virology; D000358:African Swine Fever Virus / Q000235:genetics* / Q000302:isolation & purification; D000818:Animals; D001483:Base Sequence; D004196:Disease Outbreaks; D015967:Gene Expression Regulation, Viral; D014644:Genetic Variation; D005838:Genotype; D009549:Nigeria / Q000453:epidemiology; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013552:Swine; D015678:Viral Structural Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D015678:Viral Structural Proteins
keywords: 
  CVR
  ; 
  p54
  ; 
  p72
  ; African swine fever virus; Nigeria; genetic variability; genotyping