Disease factsheet: Glanders & Farcy
If you suspect signs of any notifiable disease, you must immediately notify a Defra Divisional Veterinary Manager.
16 September 2008 - International Disease Monitoring - Preliminary Outbreak Assessment: Glanders in Brazil.
- Introduction
- Safety Precautions
- Animals affected
- Clinical signs
- Post Mortem
- Spread of the disease
- Import testing
- Eradication in Great Britain
Introduction
This disease, widespread in Great Britain in the nineteenth century, was finally eradicated from this country in 1928. It still survives in parts of Europe, Asia, Asia Minor and North Africa. Glanders is a serious bacterial disease of the respiratory tract and skin, affecting mainly equids. It is also an important zoonosis. It dates back to antiquity, having been described in Graeco-Roman times, and has caused heavy losses of horses down the centuries. It remains a notifiable disease in this country.Two forms of the same disease caused by a bacteria, Burkholderia mallei. The disease is called "Glanders" when the principal lesions are seen in the nostrils, submaxillary glands and lungs: "Farcy" when located on the surface of limbs or body.
Safety Precautions
Field veterinarians and veterinary pathologists must take strict precautions to prevent human infections, via either the cutaneous or the respiratory route, during clinical or post-mortem examination of suspected cases. Adequate protective clothing, including gloves and face masks, should be worn. Laboratory workers should carry out all manipulations in a Class 2 biological safety cabinet.
Animals affected
Horses, mules and donkeys are the species most often affected. Horses tend to be chronically affected, whereas donkeys and mules get the disease in the acute form. Apparently recovered animals remain carriers. Infection occurs by ingestion, leading to blood infection localised in the lungs, and also in the skin and the mucous membrane of the nasal passage. Humans can be infected from affected horses by inoculation through a wound. If untreated, the mortality rate in humans is as high as 95%. Dogs, cats and wild carnivora may be infected.
Clinical signs
Horses are usually infected by eating or contacting contaminated food/ water/ troughs/ tack. The disease is characterised by the formation of nodular lesions in the lung and other internal organs and ulcerations of the mucous membrane at the upper respiratory tract. In the acute form, nasal discharge, coughing, a high fever, and ulceration of the nasal mucous are symptoms of this disease. Death occurs from septicaemia in a few days. The discharges are infectious. In chronic forms, nodules develop subcutaneously and ulcerate. The lymph vessels thicken and there is enlargement of the lymph nodes of the area. Nodules develop in the nose, the turbinate bones and on the nasal septum. They enlarge up to 1cm in diameter then ulcerate. The animals are sick for months and then die or remain carriers. These carrier animals may continue to spread the disease. Diagnosis is by mallein test or a complement fixation test.
Post-mortem
The skin may show ulcers if farcy has been present. There may be ulceration of the throat and air passages. The most constant changes are, however, found in the lungs. In acute Glanders, small grey nodules about the size of a pinhead are seen all through the lung substance. In the chronic forms the nodules in the earlier stages appear as small, grey patches with a red margin. Others are of pus-like consistence. The older nodules are hard and shot-like to the touch: some of them are gritty due to calcification. The number of nodules in the lungs varies from one or two to hundreds. Donkeys can suffer from an acute form of Glanders, in which the lungs are inflamed over a large surface.The tissue is very firm, and on section of the surface of the lung has a greyish red colour.
Spread of the disease
Distribution of this disease is now restricted to some countries in the Middle East, Africa, India, SE Asia as well as China and Mongolia. Diagnosis can be made by taking samples from clinical cases. A mallien test can be formed to identify carriers. A small dose (0.1ml) of antigen is injected in the tissue below the eye. Swelling at the injection site, often with a high temperature, often indicates a potential carrier state, and can be an aid to field diagnosis.
Import testing
Horses imported to the United Kingdom from regions where there is a risk of Glanders, are routinely blood sampled on arrival in the UK. The implications for both human and equine health make this a significant disease for ongoing vigilance.
Eradication in Great Britain
As the Glanders and Farcy bacteria is spread from animal to animal, by people and other means, the only way the disease could be eradicated was by immediately slaughtering the infected horses. Strict isolation of suspected cases and contact animals was also imperative.
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Page last modified:
September 19, 2008