Genetic characterization of type 2 porcine circoviruses detected in Hungarian wild boars

Abstract

Porcine circoviruses (PCV) are present in pigs worldwide; they are grouped into two types: PCV1 comprising non-pathogenic viruses and PCV2 responsible for several clinical manifestations. Both types are frequently detected in domestic pigs, the prevalence and role of PCV in wild boars however, is not well studied. During the years 2002-2003 over 2000 organ samples of Hungarian wild boars were collected, grouped and samples from 307 different animals were tested by polymerase chain reaction for the presence of PCV. 35.5% of the wild boars were positive for one or both PCV types and PCV2 was detected in 20.5% of the animals. The PCV2 viruses were divided into 7 groups (WB-H1-7) based on sequencing data and genomes representing these groups were sequenced completely. The wild boar PCV2 groups were distributed evenly in the geographical region, regardless of the time and place of collection. The phylogenetic analysis of the PCV2 sequences of wild boar and domestic pig origin showed the possibility of an epidemiological link between wild boar and domestic pig infections. Interestingly, the complete nucleotide sequence of the viruses and the predicted amino acid sequence of the replication associated protein (ORF1) grouped the viruses similarly, whereas the capsid protein (ORF2) comparisons revealed different relations among the groups, suggesting the possibility of genomic recombination in PCV2.

Replication and transmission of porcine circovirus type 2 in mice

“…The organ samples were processed with the Chelex ® 100 Molecular Biology Grade Resin (Biorad) and the DNA from faecal and urine samples was extracted with the QIAGENE QIAamp ® DNA Stool Mini kit as recommended by the manufacturers and analysed by polymerase chain reaction (PCR) using PCVspecific primers (Cságola et al, 2006). The PCV-positive samples were examined further with PCV2-specific primers: CORF2B 5'-TAC ATA CAT GGT TAC ACG GAT ATT -3' (1078-1101 nt) and CBB2 5'-CGC ACC TTC GGA TAT AC-3' (1584-1568 nt).…”

“…However, in addition to domestic swine, PCV2 was also detected in wild boars (Sanchez et al, 2001;Ellis et al, 2003;Vicente et al, 2004;Cságola et al, 2006) and cattle (Nayar et al, 1999), and antibodies against the non-pathogenic viruses of the PCV1 group were also detected in cattle, mice and humans (Tischer et al, 1995). The presence of the virus in species other than swine is controversial, as according to another survey, PCV2 or antibodies to PCV2 were not detectable in cattle and sheep (Allan et al, 2000).…”

Detection and Genetic Characterization of Porcine Circovirus 2 Isolates From the First Cases of Postweaning Multisystemic and Wasting Syndrome in Wild Boars in Greece

“…A PCV2-antibody prevalence of 47% has been reported for wild boar sampled in Spain; antibody prevalence was highest in intensively managed populations rather than in those living in more natural conditions (Vicente et al, 2004). In addition, the incidence of PCV2 DNA in tissue samples from wild boars sampled in Hungary was 20.5% (Csagola et al, 2006).…”

“…Wild boars (Sus scrofa) infected with PCV2 have been reported (Vicente et al, 2004;Knell et al, 2005;Csagola et al, 2006). A PCV2-antibody prevalence of 47% has been reported for wild boar sampled in Spain; antibody prevalence was highest in intensively managed populations rather than in those living in more natural conditions (Vicente et al, 2004).…”

“…Genomic sequences of PCV2 isolates from domestic pigs, with or without PMWS, are closely related (De Boisseson et al, 2004). A number of PCV2 strains have been genetically characterized from wild boars with subclinical infection (Knell et al, 2005;Csagola et al, 2006), but only one has been characterized from a PMWS case (Schulze et al, 2004).…”