Glanders is a highly contagious, often fatal, and zoonotic bacterial disease in horses, caused by Burkholderia mallei. It primarily causes lesions and nodules in the respiratory tract and skin, but can also lead to a severe systemic illness in horses. While largely eradicated in many countries, it is considered a re-emerging disease in some parts of the world.
Symptoms
Acute: Fever, difficulty breathing, coughing, and thick, yellow-green nasal discharge. Small bumps or boils may be seen on the nasal mucous membrane, and the eyes may have a purulent discharge.
Chronic: Ulcerating growths on the skin and in the nose are common. This form is also called "farcy" and appears as hard, ropey nodules along the lymphatics, which can break open and discharge pus.
Weight loss: Affected horses typically lose weight dramatically.
Transmission
Ingestion: Through contaminated food or water.
Aerosol: Through contact with contaminated aerosols.
Direct contact: Through direct contact with infected animals or their discharges.
Fomites: Equipment like grooming tools or harnesses that are contaminated with the bacteria.
Insects: Flies may play a role in spreading the disease if they feed on oozing lesions.
Diagnosis and control
Diagnosis involves clinical evaluation combined with laboratory tests, such as serological assays, complement fixation tests, or culturing the bacteria.
Control and eradication depend on testing for the presence of the disease, screening all equines, and eliminating infected animals.
Risk to humans
Glanders is a zoonotic disease, meaning it can be transmitted from animals to humans.
Humans are accidental hosts, and the disease can cause a severe and often fatal illness if untreated.
Transmission to humans occurs from close contact with infected animals or their discharges.