Agricultural Disaster Preparedness and Recovery July 01, 2012 Print Friendly and PDF


What Is Pseudorabies and Why Should I Care?

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.


Where Is Pseudorabies Found?

Parts of Europe, Asia and South America. The United States and Canada are considered free of Pseudorabies.


Can Pseudorabies Affect People?

Pseudorabies is not a public health threat.


What Are The Signs Of Pseudorabies?


  • 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




  • Intense itching of a patch of skin
  • Self mutilation due to scratching
  • Weakness
  • Convulsions
  • Teeth grinding
  • Rapid,shallow breathing
  • Cardiac arrythmias
  • Bellowing
  • Death




  • 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


Can Pseudorabies Be Treated?

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.


How Can Pseudorabies Be Prevented?

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.

Where Can I Find Additional  Information?

Iowa State University-Aujeszky's Disease Fact Sheet

USDA-APHIS Pseudorabies Eradication Plan

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This work is supported by the USDA National Institute of Food and Agriculture, New Technologies for Ag Extension project.