37. Teschovirus encephalomyelitis. Flashcards
Ethiology?
Porcine polioencephalomyelitis, Teschen disease, Talfan disease
Etiology
- 1930 Teschen disease
- 1957 Talfan disease
• Occurrence
- Teschen
‣ Formerly endemic in Middle-Europe
‣ Madagascar, occurred in Russia, Romania
- Talfan
‣ Europe, America, Australia
‣ Widespread
- Teschovirus genus
- Serotype 1 ➝ virulence variants (Teschen-Talfan)
- Serotypes 2-11 ➝ milder clinical signs
Epidemiology?
Epidemiology
• Only pigs susceptible
- Teschen disease: all age groups susceptible
- Talfan disease: below 4 months of age (most frequently 3-8 weeks)
- Shedding in faeces for 7-8 weeks
- Spreading with live pigs, meat, faeces, brain, spinal cord, swill
- Resistant in the environment (about 3 weeks) ➝ indirect infection
Pathogenesis?
Pathogenesis
• Infection
- Per os
- Nose, olfactory nerves ➝ CNS
• Enteral phase
- Gastrointestinal tract (lymphoid tissues) ➝ primary replication
- Asymptomatic, seroconversion, shedding the virus (majority)
- Local immunity, virus shedding will be finished
- Viraemic phase ➝ fever
- Neural phase
- Secondary virus replication
- Meningitis, encephalomyelitis, necrosis of neurons, clinical signs
Clinical signs of Teschen disease?
Clinical signs of Teschen disease
- Incubation: 1-3 weeks
- Mild fever, anorexia
- Vomiting
- Ataxia, convulsions
- Flaccid paralysis
- Respiratory paralysis
- Hyperaesthesia
- Piglet, grower
- Adults ➝ flaccid paralysis of the hindlimb
- Some animals may recover, clinical signs remain
Clinical signs of taflan disease?
Clinical signs of Talfan disease
- Piglets below 4 months go age, mainly before weaning (3-8 weeks)
- Ataxia, paralysis of the hindlimb (transient)
- Recover, ataxia can remain
Pathology?
Pathology
- No gross pathologic lesions
- Histopathological lesions
- Lymphocytic infiltration, necrosis (Teschen), degeneration
‣ Grey matter of the brain (serotype 2 also white matter)
‣ Brain stem
‣ Cerebellum
‣ Ventral horns of the spinal cord
• Diagnostic examination: live piglet
Diagnosis and differential diagnosis?
Diagnosis
- Epidemiology ➝ clinical signs ➝ post mortem lesions ➝ histology
- Detection of the virus
- RT-PCR, IF, IP
- Isolation of the virus
• Detection of the antibodies
- VN: increasing titre, paired samples
• Differential diagnosis
- Infective
‣ Classical swine fever
‣ African swine fever
‣ Aujeszky disease
‣ Rabies
‣ Oedema disease
‣ Glasser’s disease
‣ Streptococcosis
- Non-infective
‣ Water deprivation
‣ Sal intoxication
Treatment, prevention and control?
Treatment
• None
Prevention, Control
- Notifiable disease in Hungary
- OIE: not listed disease
- General epidemiological measures
- Teschen disease
- Movement restriction
- Stamping out
- Talfan disease ➝ seroconversion
- Vaccine
- Inactivated and live vaccines in the past
- No vaccines are available now
