Porcine torque teno virus vaccines and diagnosis

A vaccine comprising a nontoxic, physiologically acceptable carrier and an immunogenic amount of a member selected from the group consisting of:

• (a) a nucleic acid molecule containing at least one copy of genomic sequence having at least 80% homology to a genomic sequence selected from the group consisting of PTTV genotypes or subtypes PTTV1a-VA, PTTV1b-VA, PTTV2b-VA, and PTTV2c-VA, or its complementary strand;
• (b) a biologically functional plasmid or viral vector containing a nucleic acid molecule containing at least one copy of genomic sequence having at least 80% homology to a genomic sequence selected from the group consisting of PTTV genotypes or subtypes PTTV1a-VA, PTTV1b-VA, PTTV2b-VA, and PTTV2c-VA, or its complementary strand;
• (c) an avirulent, infectious nonpathogenic porcine Torque teno virus, which is derived from and contains a genomic sequence having at least 85% homology to a genomic sequence selected from the group consisting of PTTV genotypes or subtypes PTTV1a-VA, PTTV1b- VA, PTTV2b-VA, and PTTV2c-VA;
• and
• (d) an immunogenic fragment of a polypeptide sequence or a complete protein translated according to a polynucleotide sequence selected from the group consisting of ORF1, ORF2, ORF1/1, and ORF2/2 of PTTV genotypes or subtypes PTTV1a-VA, PTTV1b- VA, PTTV2b-VA, and PTTV2c-VA.

A method for diagnosing PTTV1 infection and quantification of PTTV1 load, comprising:

• extracting DNA from a sample suspected of PTTV1 infection;
• performing polymerase chain reaction (PCR) using primers comprising the sequences set forth in SEQ ID NO:29 and SEQ ID NO:30;
• and
• detecting PTTV1 specific amplification.

A method for diagnosing PTTV2 infection and quantification of PTTV2 load, comprising:

• extracting DNA from a sample suspected of PTTV2 infection;
• performing polymerase chain reaction (PCR) using primers comprising the sequences set forth in SEQ ID NO:29, SEQ ID NO:30, SEQ ID NO:31 and SEQ ID NO:32;
• and
• detecting PTTV2 specific amplification.

A method for simultaneously detecting and diagnosing PTTV1 and PTTV2 infection, comprising:

• extracting DNA from a sample suspected of PTTV infection;
• performing polymerase chain reaction (PCR) using primers comprising the sequences set forth in SEQ ID NO:31 and SEQ ID NO:32;
• and
• detecting PTTV1 and PTTV2 specific amplification.

A method for simultaneously detecting and diagnosing PTTV1a and PTTV1b infection, comprising:

• extracting DNA from a sample suspected of PTTV1 infection;
• performing a first polymerase chain reaction (PCR) using primers comprising the sequences set forth in SEQ ID NO:33 and SEQ ID NO:34;
• performing a second PCR using primers comprising the sequences set forth in SEQ ID NO:35, SEQ ID NO:36, SEQ ID NO:37, and SEQ ID NO:38;
• and
• detecting PTTV1a and PTTV1b specific amplification.

A method for diagnosing PTTV infection, comprising

• immobilizing an immunogentic fragment or a complete protein of a polypeptide sequence translated according to a polynucleotide sequence selected from the group consisting of ORF1, ORF2, ORF1/1, and ORF2/2 of PTTV subtypes PTTV1a-VA, PTTV1b- VA, PTTV2b-VA, and PTTV2c-VA;
• contacting a serum sample from a pig suspected of PTTV infection with the immobilized immunogentic fragment or complete protein;
• and
• detecting captured antibody specific to the immunogentic fragment.