Safeguarding public and animal health
Classical swine fever
What is classical swine fever?
Classical swine fever (CSF) is a very contagious disease of pigs. It is caused by highly infectious viral disease called pestivirus.
The virus can infect pigs via a number of routes:
- respiratory/oral route
- swill feeding (feeding animal material)
- direct contact
- personnel or vehicles bringing disease from another farm
- infected artificial semen insemination.
Clinical signs
The principal feature of this disease is that clinical signs can vary greatly and can range from very severe to very mild or sub-clinical. The pathogenicity of the strain dictates the clinical signs:
- Highly pathogenic strains can kill pigs of all ages.
- Moderate or low-virulent strains are more common and may be virtually unapparent in adult animals and only kills piglets.
CSF in the UK
There was an outbreak of classical swine fever in the UK in 2000. Although there had not been an outbreak of CSF for 14 years, VLA had maintained its research and surveillance activities which enabled us to respond very quickly to the crisis by providing large scale testing or samples. This resulted in the outbreak being successfully controlled.
Wild boars
The British wild boar population originate from farmed and captive boar and does not carry CSF. VLA, in collaboration with the Food and Environment Research Agency (Fera), has carried out a study into the potential risks of the UK wild boar becoming infected and spreading CSF.
Diagnosis
There are a number of tests available to detect the CSF virus. They include:
- the fluorescent antibody test
- virus isolation
- antigen detection, and
- the highly sensitive and specific viral DNA test developed by VLA, which uses TaqMan RT-nPCR to recognise the specific genome sequence of the CSF virus.
Selected scientific papers
Bensaude, E, Turner, J L E, Wakeley, PR, Sweetman, D A, Pardieu, C, Drew, T W, Wileman, T, and Powel, P P (2004). Classical swine fever virus induces proinflammatory cytokines and tissue factor expression and inhibits apoptosis and interferon synthesis during the establishment of long-term infection of porcine vascular endothelial cells. Journal of General Virology 85, 1029-1037.
La Rocca, S A, Herbert, RJ, Crooke, H., Drew, T W, Wileman, T E, and Powell, P P (2005). Loss of interferon regulatory factor 3 in cells infected with classical swine fever virus involves the N-terminal protease, Npro. Journal of Virology 79, 7239-47.
Classical swine fever is a notifiable disease and therefore you must contact your local Animal Health Office if you suspect signs of the disease.