Further evidence of the host plasticity of porcine circovirus-2: detection of the virus in domestic dogs in Namibia

• Published in: BMC veterinary research Vol. 21; no. 1; p. 162
• Main Authors: Molini, Umberto, de Villiers, Lourens, Coetzee, Lauren M., Green, Herschelle P., de Villiers, Mari, Khaiseb, Siegfried, Cattoli, Giovanni, Dundon, William G., Franzo, Giovanni
• Format: Journal Article
• Language: English
• Published: London BioMed Central 12.03.2025; BioMed Central Ltd; BMC
• Subjects: Advances in canine health research; Animals; Asia; blood; Carnivores; Circoviridae Infections - epidemiology; Circoviridae Infections - veterinary; Circoviridae Infections - virology; Circovirus - genetics; Circovirus - isolation & purification; Datasets; Diagnosis; direct contact; Disease; Disease transmission; Diseases; Distribution; DNA virus infections; DNA viruses; Dog; Dog Diseases - epidemiology; Dog Diseases - virology; Dogs; Domestic animals; Epidemiology; Food contamination; Genetic aspects; Genomes; Genotype; Genotype & phenotype; Genotypes; Heparan sulfate; Hogs; Host; Host-virus relationships; Identification and classification; industry; Infections; ingestion; Meat; Medicine; Medicine & Public Health; Molecular epidemiology; Mutation; Namibia; Namibia - epidemiology; nutrition; Pathogens; PCV-2; Phylogenesis; Phylogenetics; Phylogeny; Plasticity; Porcine circovirus-2; pork; probability; raw meat; Risk factors; species; Statistical analysis; Strains (organisms); Swine; Swine Diseases - epidemiology; Swine Diseases - virology; Transgenics; Veterinary Medicine/Veterinary Science; Viruses; Zoology; Namibia; United States > US; Italy; Asia; Molecular epidemiology; Phylogenesis; Host; Dog; Namibia; PCV-2
• ISSN: 1746-6148; 1746-6148
• DOI: 10.1186/s12917-025-04581-7

Porcine circovirus 2 (PCV-2) is a major pathogen of swine, causing significant production losses in the pig industry worldwide. Several studies have detected the virus in different species, both in asymptomatic and diseased subjects, highlighting PCV-2 host plasticity. As PCV-2 has been identified in carnivores, the present study was undertaken to investigate the susceptibility of domestic dogs to PCV-2 infection by testing archived blood samples originating from low-income rural areas in Namibia. The population was selected considering the high exposure probability to PCV-2 due to direct contact and/or feeding with raw pig meat or by-products. Thirty-eight of the samples (6.61%) tested positive for PCV-2, and the complete ORF2 of 7 strains was sequenced, revealing the presence of the three major PCV-2 genotypes (i.e. PCV-2a, -2b, and -2d). Convincing epidemiological links with other Namibian and South African strains were established for PCV-2a and PCV-2b strains, while the PCV-2d strains were part of a broader clade that included sequences of viruses collected worldwide, especially in Asia. Although PCV-2 was reported in diseased dogs, no statistically significant or robust causal association between infection and disease manifestation was demonstrated. In conclusion, PCV-2 infection has been identified in Namibian dogs, most likely due to the ingestion of contaminated meat and by-products. However, the epidemiological and clinical consequences are still unclear and further investigations are necessary. Nevertheless, the high proportion of infected dogs showing clinical signs raises concern about the potential of PCV-2’s role as a relevant viral pathogen in Namibia. The use of raw meat for dog nutrition should be discouraged, considering the known risks to animal and human health through disease transmission.