ARCHIVE: Aujeszky's disease

If you suspect signs of any notifiable disease, you must immediately notify a Defra Divisional Veterinary Manager.

History and spread of the disease

Aujeszky's disease is also known as pseudorabies, in which form it was first noticed in cattle in the United States of America in 1813. The first case of Aujeszky's disease in Great Britain was in 1979, the last in 1989. GB was declared officially free of this disease in 1991 following extensive serum surveys. The eradication programme was funded by a levy on all pig producers in the form of the Pig Disease Eradication Fund.

The disease had not existed widely outside Eastern Europe before the 1960s but by 1989 it had a world-wide distribution affecting 43 countries.

There are several reasons for this. New and more virulent strains may have emerged in recent decades: improvements in diagnostic techniques may have revealed cases of Aujeszky's that had previously been diagnosed as swine fever, and changes in swine management, notably total confinement of large numbers of pigs and continuos farrowing, may have contributed to increased incidence of this disease.

Clinical signs

Pigs are the only natural host for the Aujeszky's virus, although it can infect cattle, sheep, cats, dogs and rats causing fatal disease. Clinical signs of the disease in pigs vary depending on the age of the pigs involved. In neonatal pigs the incubation period is 2-4 days and signs of central nervous system disease (shivering, inco-ordination and hind leg weakness) are seen. Losses may reach 100% in piglets less than 7 days old.

In weaned pigs, respiratory disease is the predominant problem. Sneezing, coughing and laboured breathing is accompanied by fever and weight loss. Signs in gilts and sows include abortion, stillbirth, mummified foetuses in addition to the respiratory and febrile signs seen in growing and finishing pigs.

Mortality rates tend to decrease as the age of the affected pigs rises. Clinical signs can be present for 6-10 days. In uncomplicated cases the animals often recover.
Diagnosis is usually made using a combination of herd history, clinical signs, virus isolation, fluorescent antibody testing and serology. Photos of clinical signs...

Main aspects of disease control

There is no specific treatment for acute infection. Vaccination would alleviate the clinical signs and is used in some countries. In Great Britain a slaughter policy exists to control the disease and on confirmation of disease:-

(i) Form A will be served on the infected premises, restricting movements into and out of the premises,

(ii) Whole herd slaughter with compensation,

  • apparently healthy and marketable pigs will be transported to a slaughterhouse
  • sick and unmarketable pigs will be slaughtered on the premises,

(iii) Cleansing and disinfection of the premises and removal of restrictions.

Legislation - Great Britain

The Aujeszky's Disease Order 1983 requires the notification of suspected disease in animals and slaughter of pigs on infected premises. It also provides for movement controls on all animals and products onto and off an infected premises and movement control of pigs within an infected area.

The Diseases of Animals (Seizure) Order 1993 provides powers to seize and destroy anything other than a live animal in order to prevent the spread of disease.

The Pig Industry Levy Act 1983 empowers the Meat and Livestock Commission to collect a levy to cover the cost of compensation for the value of pigs and other things destroyed to prevent the spread of disease. The Pig Disease Eradication Fund is held by a company registered by the National Farmers' Union. Since Great Britain declared freedom from Aujeszky's disease, collection of the levy on finished pigs at slaughterhouses has ceased, but a reserve fund is retained and the mechanism to restart the levy remains in place.

The Animal By-Products (Amendment) (England) Order 2001 prohibits the feeding of catering waste to livestock and the bringing of catering waste onto livestock premises.

Compensation

The Aujeszky's Disease (Compensation for Swine) Order 1983 provides that the compensation shall be the animal's market value immediately before it was slaughtered had it not been affected with or exposed to Aujeszky's disease, subject to a maximum of £300.

Legislation - EU

Aujeszky’s disease is compulsorily notifiable in the EU, but there is no specific EU legislation laying down detailed measures for controlling outbreaks of this disease. However, Aujeszky’s disease is included in the requirements of Council Directive 90/429 laying down animal health requirements applicable to intra-Community trade and imports of semen of domestic animals of the porcine species, and in Council Directive 97/12 amending and updating Directive 64/432/EEC on health problems affecting intra-Community trade in bovine animals and swine.

In addition, Commission Decisions 93/24 and 93/244 now revoked and replaced by Commission Decision 2001/618/EC concerned additional guarantees relating to pigs destined for certain parts of the territory of the Community or to Member States or regions free of the disease.

In addition, there is:

Commission Decision 2001/618/EC (PDF Link to EU website) of 23 July 2001 concerning additional guarantees to Aujeszky's disease for pigs destined for certain parts of the territory of the Community.

Commission Decision 2004/212/EC (PDF Link to EU website) of 6 January 2004 on Community health conditions on imports of animals and fresh meat including minced meat from third countries and amending Decisions 79/542/EEC, 2000/572/EC and 2000/585/EC includes provision for guarantees of freedom from Aujeszky's disease.

Commission Decision 2004/320/EC (PDF Link to EU website) of 31 March 2004 amended Decisions 93/52/EEC, 2001/618/EC and 2003/467/EC as regards the status of acceding countries with regard to brucellosis (B. melitensis), Aujeszky's disease, enzootic bovine leukosis, bovine brucellosis and tuberculosis and of France with regard to Aujeszky's disease.

Most recent GB outbreak

The last confirmed cases were five cases in 1989, when 1,373 animals were slaughtered, of which 1,029 were salvaged.

Related Pages

 

Page last modified: September 9, 2009