Virion

Morphology

No surface morphology is visible by EM.

Physicochemical and physical properties

Virions are stable at acid pH. Buoyant density in CsCl is 1.33 g cm^-3. Empty capsids are often observed in virus preparations.

Nucleic acid

Length of genome (Zell et al., 2001, Buitrago et al., 2010, Boros et al., 2012b): >7,110 nt (5'-proximal sequence missing) (5'-UTR: >335 nt; ORF: 6,600-6,711; 3'-UTR: 67 nt). Teschoviruses have a type IV IRES about 290 nt in length which is functional in the absence of eIF-4G. The location of the cre is thought to be within the 2C region.

Genome organization and replication

Genome layout:

VPg+5'UTR^IRES-IV[L/1A-1B-1C-1D-2A^npgp/2B-2C/3A-3B-3C-3D]3'UTR-poly(A)

The deduced polyprotein vary in length from 2,199-2,236 aa. The function of the leader polypeptide is unknown and is not predicted to have proteolytic activity. 2A is a short FMDV-like polypeptide with NPG↓P motif.

Antigenicity

Porcine teschoviruses are divided into 13 types (PTV-1 to -13) which are distinct in cross-neutralization tests (where tested).

Biology

Clinical manifestations may include a polioencephalomyelitis (“Teschen/Talfan disease”, also known as teschovirus encephalomyelitis), which may vary in severity. The viruses have been associated with a number of disease syndromes, including reproductive and gastrointestinal disorders. Domestic pigs and wild boars are the only known hosts.

Species demarcation criteria

Not applicable

Member species

Virus names, the choice of exemplar isolates, and virus abbreviations, are not official ICTV designations.

Derivation of names

Tescho: from Teschen disease, named after the Moravian-Silesian town Teschen (now Těšín at the Czech/Polish border).