Studies of porcine circovirus type 2, porcine boca-like virus and torque teno virus indicate the presence of multiple viral infections in postweaning multisystemic wasting syndrome pigs.
In a previous study, using random amplification and large-scale sequencing technology, we identified a novel porcine parvovirus belonging to the genus Bocavirus in the background of porcine circovirus type 2 (PCV-2) in Swedish pigs with postweaning multisystemic wasting syndrome (PMWS). In addition to bocavirus we demonstrated the presence of torque teno virus (TTV) genogroups 1 and 2 in these cases of PMWS, indicating the simultaneous presence of several viruses in this disease complex. In the present study, 34 PMWS-affected animals and 24 pigs without PMWS were screened by PCR for the presence of PCV-2, TTV-1, TTV-2 and porcine boca-like virus (Pbo-likeV). The studies revealed the following infection rates in the PMWS-affected pigs: PCV-2 100%, TTV-1 77%, TTV-2 94% and Pbo-likeV 88%. In comparison, the pigs without PMWS had the following rates: PCV-2 80%, TTV-1 79%, TTV-2 83% and Pbo-likeV 46%. The sequence identity between the different Swedish Pbo-likeV sequences ranged between 98% and 100%. By checking co-infection, it was found that 71% of the PMWS-affected pigs harbor simultaneously all these viruses. As a contrast, in the group without PMWS only 33% of the animals were positive simultaneously for these viruses. These observations indicate a multiple viral infection in PMWS-affected pigs. It has to be studied further if the clinical manifestation of PMWS might be due to synergistic effects of different viruses acting together.
Blomström
Anne-Lie
AL
Department of Biomedical Sciences and Veterinary Public Health, Section of Virology, Swedish University of Agricultural Sciences, Uppsala, Sweden. Anne-Lie.Blomstrom@bvf.slu.se
Belák
Sándor
S
Fossum
Caroline
C
Fuxler
Lisbeth
L
Wallgren
Per
P
Berg
Mikael
M
D000595:Amino Acid Sequence; D000818:Animals; D018173:Circoviridae Infections / Q000662:veterinary* / Q000821:virology; D017925:Circovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D004266:DNA Virus Infections / Q000662:veterinary* / Q000821:virology; D008969:Molecular Sequence Data; D010802:Phylogeny; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000821:virology*; D016415:Sequence Alignment; D013548:Sweden; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D022783:Torque teno virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics
D014764:Viral Proteins