Pig Pox

Also known as: Swinepox

Introduction

Pig pox is of the family Poxviridae, which is a double stranded DNA virus, which causes cell proliferation followed by a central necrosis, leading to the presence of a typical 'pock' lesion. The virus can survive off the pig or off the louse for long periods of time and is resistant to many environmental changes.

Haematopinus suis, is the only louse of pigs and this is the vector for African Swine Fever and Swinepox. The disease can also be transmitted through skin abrasions or through injuries caused when fighting.

Signalment

Pigs of any age, breed or sex can be affected by the disease, however it is uncommon in piglets.

Clinical Signs

Signs on the skin include small circular red areas around 10-20mm in diameter that commence with lesion containing straw-coloured fluid in the centre. After two to three days the lesion ruptures and a scab is formed which gradually turns black. The lesions may be seen on any part of the body but are common along the flank, abdomen and occasionally the ears. A secondary dermatitis may occur if contaminated by bacteria.

Diagnosis

Diagnosis is usually by the presence of characteristic lesions. It can be confused with greasy pig disease or pustular dermatitis, but closer inspection will show evidence of pock lesions.

Treatment and Control

Lice control is an important control mechanism as these are the main vector for the disease. Good hygiene protocols and management systems e.g. preventing mixing of pigs of different ages to prevent fighting etc are useful control measures.

There are no vaccines available as the disease is not considered serious enough to warrant the production of one.

References

Bridger, J and Russel, P (2007) Virology Study Guide, Royal Veterinary College

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

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

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