PICORNAVIRIDAE

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PICORNAVIRIDAE

• PETER H. RUSSELL, BVSc, PhD, FRCPath, MRCVS
• Department of Pathology and Infectious Diseases,
  The Royal Veterinary College,
• Royal College Street,
• London NW1 OTU.
• E-mail Web site

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ObjectiveStudents should be able to

• be aware of swine vesicular disease as a
  notifiable disease.
• evaluate rhinoviruses as pathogens of the upper
  respiratory tract.
• describe in detail the importance of serotypes,
  subtypes and virus protein 1(VP1) of foot and
  mouth disease virus (FMDV) notifiable disease.
• compare and contrast the methods of control of
  FMDV in the EU and endemic areas

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General properties
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ENTEROVIRUSES

• SWINE VESICULAR DISEASE (SVD)

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ENTEROVIRUSES

• (cont.)

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GENUS APTHOVIRUS

• FOOT AND MOUTH DISEASE VIRUS

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VIRUS

• The RNA is translated into a single polyprotein
  which is cleaved into the 4 virus proteins by a
  viral protease.

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VIRUS

• Physio-Chemical Properties

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VIRUS

• Serotypes on VP1

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VIRUS

• Subtypes

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PATHOGENESIS AND CLINICAL SIGNS

• Primary replication is at the epithelium of the
  upper respiratory tract or alimentary tract.
  Aerosol virus is excreted during this incubation
  period. After viraemia the virus targets the
  stratum spinosum of stratified squamous epithelia
  and mucous membranes where external secondary
  vesicles appear after an incubation period of
  2-14 days.

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TRANSMISSION
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IMMUNITY
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DIAGNOSIS
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CONTROL

• UK
• !!!!!
• YOU MUST REPORT CLINICAL LESIONS- MILK DOWN,
  LAMENESS, BLANCHED EPITHELIUM PROGRESSING TO
  VESICLES, CRUSTS, SALIVATION.
• !!!!

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CONTROL

• Slaughter and disinfection.

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ENDEMIC AREAS
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The vaccines
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Summary

• FMDV is exotic to the UK and a notifiable disease
  with attempts to contain the disease within
  infected areas.
• Rapid slaughter of infected animals, after
  confirmation by ELISA for serotype in vesicle
  fluid.
• Vaccinate with 2-3 circulating subtypes in an
  endemic area.