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. 2023 Oct 26;15(11):2157.
doi: 10.3390/v15112157.

Evidence of Porcine Circovirus Type 2 (PCV2) Genetic Shift from PCV2b to PCV2d Genotype in Sardinia, Italy

Silvia Dei Giudici  1 , Lorena Mura  1 , Piero Bonelli  1 , Salwa Hawko  2 , Pier Paolo Angioi  1 , Anna Maria Sechi  1 , Stefano Denti  1 , Antonella Sulas  1 , Giovanni Pietro Burrai  2 , Maria Paola Madrau  1 , Elisabetta Antuofermo  2 , Annalisa Oggiano  1
Affiliations

Evidence of Porcine Circovirus Type 2 (PCV2) Genetic Shift from PCV2b to PCV2d Genotype in Sardinia, Italy

Silvia Dei Giudici et al. Viruses. .

Abstract

Porcine Circovirus type 2 (PCV2) is the etiological agent of a disease syndrome named Porcine Circovirus disease (PCVD), representing an important threat for the pig industry. The increasing international trade of live animals and the development of intensive pig farming seem to have sustained the spreading of PCVD on a global scale. Recent classification criteria allowed the identification of nine different PCV2 genotypes (PCV2a-i). PCV2a was the first genotype detected with the highest frequency from the late 1990s to 2000, which was then superseded by PCV2b (first genotype shift). An ongoing genotype shift is now determining increasing prevalence rates of PCV2d, in replacement of PCV2b. In Italy, a complete genotype replacement was not evidenced yet. The present study was carried out on 369 samples originating from domestic pigs, free-ranging pigs, and wild boars collected in Sardinia between 2020 and 2022, with the aim to update the last survey performed on samples collected during 2009-2013. Fifty-seven complete ORF2 sequences were obtained, and the phylogenetic and network analyses evidenced that 56 out of 57 strains belong to the PCV2d genotype and only one strain to PCV2b, thus showing the occurrence of a genotype shift from PCV2b to PCV2d in Sardinia.

Keywords: Porcine Circovirus type 2; genetic shift; phylogenetic analysis.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
A maximum likelihood phylogenetic tree inferred from the first data set by the GTR+G+I model of nucleotide substitution. Isolates under study are indicated with different symbols. Red triangles: wild boar; green circles: domestic pigs; purple diamonds: free-ranging pigs. Bootstrap values < 70 are not shown. The scale bar indicates the number of substitutions per site.
Figure 2
Figure 2
A maximum likelihood phylogenetic tree inferred from the second data set by the GTR+G+I model of nucleotide substitution. Isolates under study are indicated with different symbols. Red triangles: wild boar; green circles: domestic pigs; purple diamonds: free-ranging pigs. Sequences from our previous work are highlighted in bold. Bootstrap values < 70 are not shown. The scale bar indicates the number of substitutions per site.
Figure 3
Figure 3
The haplotype network built on 138 ORF2 sequences extracted from the second dataset (Table S2). The geographical distribution of the haplotypes is indicated by different colours as shown in the legend. The size of the circles is proportional to the frequency of each haplotype. The number of mutations distinguishing the haplotypes is shown by hatch marks.
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References

    1. Tischer I., Gelderblom H., Vettermann W., Koch M.A. A very small porcine virus with circular single-stranded DNA. Nature. 1982;295:64–66. doi: 10.1038/295064a0. - DOI - PubMed
    1. Allan G.M., McNeilly F., Cassidy J.P., Reilly G.A.C., Adair B., Ellis W.A., McNulty M.S. Pathogenesis of porcine circovirus; experimental infections of colostrum deprived piglets and examination of pig foetal material. Vet. Microbiol. 1995;44:49–64. doi: 10.1016/0378-1135(94)00136-K. - DOI - PubMed
    1. Segalés J. Porcine circovirus type 2 (PCV2) infections: Clinical signs, pathology and laboratory diagnosis. Virus Res. 2012;164:10–19. - PubMed
    1. Opriessnig T., McKeown N.E., Harmon K.L., Meng X.J., Halbur P.G. Porcine Circovirus Type 2 Infection Decreases the Efficacy of a Modified Live Porcine Reproductive and Respiratory Syndrome Virus Vaccine. Clin. Vaccine Immunol. 2006;13:923–929. - PMC - PubMed
    1. Harding J.C.S., Clark E.G., Strokappe J.H., Willson P.I.E.J. Postweaning multisystemic wasting syndrome: Epidemiology and clinical presentation. J. Swine Health Prod. 1998;6:249–254.

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