Introduction to Glanders
Glanders is a zoonotic disease primarily affecting horses, donkeys, and mules, caused by the bacterium Burkholderia mallei. Historically recognized for its significant impact on equine populations and, by extension, on human societies reliant on these animals, glanders is a disease of both historical and contemporary importance due to its potential use in bioterrorism.
Pathophysiology of Glanders
The pathogen Burkholderia mallei is a highly infectious, non-motile gram-negative bacterium. It primarily infects the mononuclear phagocytic system, causing ulcers and nodules in the upper respiratory tract, lungs, and skin. The disease manifests in two forms: acute and chronic, with the former being more severe, often leading to rapid health decline and death.
Acute Glanders
Acute glanders are characterized by fever, muscle pain, mucopurulent nasal discharge, and the development of nodular lesions in the lungs. If glanders are left untreated, the infection can spread to the bloodstream, leading to septicemia and death.
Chronic Glanders
Chronic glanders present with more subtle symptoms that persist over time, including weight loss, intermittent fever, and the development of multiple small abscesses in the muscles and skin. This form can be particularly challenging to diagnose and may persist for years.
Transmission and Epidemiology
Animal to Human Transmission
Glanders are primarily transmitted to humans that have had contact with infected animals or their infected bodily fluids. Veterinarians, stable workers, and laboratory personnel are at higher risk due to their occupational exposure.
Human to Human Transmission
While exceedingly rare, human-to-human transmission can occur through close contact with an infected individual’s excretions or cutaneous eruptions.
Diagnosis of Glanders
Diagnosis is typically confirmed through the isolation of Burkholderia mallei from a clinical specimen or by serological testing. Polymerase chain reaction (PCR) assays offer a rapid and sensitive method to detect the presence of the bacterium.
Treatment and Management
Treatment involves a regimen of antibiotics such as ceftazidime, sulfadiazine, or a combination of tetracycline and streptomycin. Due to the potential for antibiotic resistance, treatment may need to be prolonged and closely monitored.
Prevention and Control Measures
Preventive measures include strict biosecurity protocols, regular screening of equine populations, and the use of personal protective equipment (PPE) for individuals at risk of exposure.
Public Health Implications
The potential use of Burkholderia mallei as a biological weapon makes glanders a disease of concern for public health authorities worldwide. Surveillance and rapid response capabilities are crucial for addressing potential outbreaks.
Conclusion
Glanders, while rare, remains a disease of significance due to its severe impact on health, its potential for wider transmission, and its implications for bioterrorism. Ongoing research, surveillance, and education are vital to managing and prevent this disease effectively.
