Suid Herpesvirus 1

Also know as: Aujeszky's Disease — Pseudorabies — Mad Itch

Introduction

This disease is notifiable and exotic to the UK. It is still present in Ireland and is not notifiable there. It is present worldwide and is particularly a problem in Eastern Europe. The virus can affect pigs, cattle, horses, cats, dogs and sheep.

The virus affects all animals differently, for instance, in sows, aerosol transmission causes bronchopneumonia followed by viremia, where as in piglats the virus spreads to neurons, causing encephalitis with convulsions. In other animals the air-borne virus can infect a skin wound and cause pruritus (mad itch), followed by encephalitis.

The latent virus can reactivated by stress, such as mixing of stock or transport.

Clinical Signs

Clinical signs vary with different species of animal.

In sows, where the virus causes bronchopneumonia, signs include coughing, serous nasal discharge, increased respiratory rate, increased lung sounds on auscultation and pyrexia and general malaise. Some sows will recover, but in others the disease will cause abortion and occasional death. In piglets, signs are much more severe and many die within 2 days. Signs include pyrexia, malaise, severe depression and convulsions.

In other animals, signs include a severe pruritus followed by encephalitis and signs such as convulsions etc.

Diagnosis

Diagnosis can be by ELISA in order to detect virus antibody.

Control

In countries where the disease is endemic, such as Ireland and Europe, there is a vaccine available. These are E-deleted marker vaccines that work by stimulating cell-mediated immunity.

References

Blood, D.C. and Studdert, V. P. (1999) Saunders Comprehensive Veterinary Dictionary (2nd Edition) Elsevier Science

Cowart, R.P. and Casteel, S.W. (2001) An Outline of Swine diseases: a handbook Wiley-Blackwell

Jackson, G.G. and Cockcroft, P.D. (2007) Handbook of Pig Medicine Saunders Elsevier

Straw, B.E. and Taylor, D.J. (2006) Disease of Swine Wiley-Blackwell

Taylor, D.J. (2006) Pig Diseases (Eighth edition) St Edmunsdbury Press ltd