Pseudorabies (Aujeszky's disease) is a herpes virus disease of pigs. The disease can cause high death rates in piglets but is relatively mild in older pigs. The virus can be transmitted to other animals including cattle, dogs and cats, in which it causes neurological signs including intense scratching and self mutilation, giving the disease the name "Mad Itch". Pseudorabies is rapidly fatal in cattle, sheep, dogs and cats. Pseudorabies is not the same as rabies.
Pseudorabies can spread through direct pig-to-pig contact; contact with contaminated feces or urine; contact with contaminated feed, bedding, equipment or clothing; and through airborne transmission. The pseudorabies virus can 'hide' in the pig's nerve endings and flare up under conditions of stress such as transport and slaughter. Even seemingly healthy pigs can shed the pseudorabies virus.
In 1997, the USDA announced guidelines for a Pseudorabies Eradication plan. As part of this plan, Pseudorabies-infected herds were depopulated and/or vaccinated and indemnity paid to the farmers. Today, the US is free of pseudorabies. Some feral pigs carry a weakened version of the virus, but this version does not seem to cause disease in either feral or domestic swine.
Endemic Areas
Parts of Europe, Asia and South America. The United States and Canada are considered free of Pseudorabies.
Clinical Signs
Piglets
- Sudden death (especially in very young pigs)
- Fever
- Anorexia
- Weight loss
- Tremors
- Paddling
- Seizures
- 'Goose-stepping'
- Vomiting (especially in older piglets)
- Hindleg paralysis
- Circling
Weaned Pigs
- Fever
- Anorexia (poor appetite)
- Sneezing
- Coughing
- Difficulty breathing
- weight loss
- Conjunctivitis
- Occasional nervous signs (tremors, paralysis, seizures)
Adult Pigs
- Mild or inapparent illness (most common)
- Respiratory symptoms, sometimes progressing to pneumonia
- Neurologic signs (muscle tremors ,convulsions)
- Pregnant sows: Abortion, reabsorbtion of infected fetuses, or giving birth to
weak, trembling neonates
Cattle,sheep,goats
- Intense itching of a patch of skin
- Self mutilation due to scratching
- Weakness
- Convulsions
- Teeth grinding
- Rapid,shallow breathing
- Cardiac arrythmias
- Bellowing
- Death
Dogs,cats
- Intense itching of a patch of skin
- Self mutilation due to scratching
- Weakness
- Convulsions
- Rapid,shallow breathing
- Cardiac arrythmias
- Vocalizing
- Neurologic signs
- Paralysis of throat muscles
- Profuse salivation
- Death
Treatment
There is no specific treatment for Pseudorabies. Any animal suspected of having Pseudorabies should be reported to the State Veterinarians or USDA Area Veterinarian in Charge immediately.
Prevention
Vaccination to prevent pseudorabies is not done in the United States. The best way to prevent the entry and spread of pseudorabies in the United States is to employ basic farm biosecurity procedures. These procedures should include the quarantine of any pig of unknown health status, following an all-in, all-out movement protocol and discouraging visitors from interacting with the pigs.
Public Health
Pseudorabies is not a public health threat.
