Author: Momina Hammad
Final-Year DVM Student University of Veterinary and Animal Sciences (UVAS), Lahore
Glanders is an important zoonotic and highly contagious infection caused by Burkholderia mallei. It mainly affects horses, donkeys, mules and humans.
Glanders is a worldwide issue that is mainly reported in Pakistan, China, Russia, Vietnam, Bangladesh and Iran. Ongoing cases of glanders in Brazil leads to economic loss as it is affecting equine trade.
B. mallei is a bioterrorism agent of ancient times and was used by military. We consider it as a possible biological weapon.
There are multiple forms of glanders. Cutaneous glanders (farcy) is a chronic form of glanders which mainly affects lymphatic system and skin, forming nodular skin lesions which cause pain and swelling. These lesions ulcerate later and drain for longer periods of time. Systemic glanders causes fever ,septicemia and abscess in organs such as liver, spleen and kidney. Pulmonary glanders lead to pneumonia, pleuritis and pulmonary abscesses. Since its effects are similar to other infectious conditions, it is difficult to diagnose it at early stages.
It is mainly transmitted to humans via inhalation, wounds or broken skin barrier. Diagnosis of human glanders requires isolation and identification of B. mallei. In animals, diagnosis involves Mallein testing along with the culture and PCR of B. mallei .
In a Lahore outbreak that involved 23 horses, were treated with 12 week program of doxycycline, enrofloxacin and trimethoprim. Since treatment of glanders is challenging due to ability of zoonotic transmission, treatment is not recommended. However, culling and euthanasia of infected horses is a wise act to control transmission of glanders.
B. mallei is resistant to many antimicrobials and thus human treatment requires prolonged combination of antimicrobials. Treatment usually begins with an intensive phase lasting 10 to 14 days, during which intravenous antibiotics such as ceftazidime, imipenem, or meropenem are given. This is followed by a longer treatment phase of 3 to 6 months using oral antibiotics such as doxycycline or trimethoprim-sulfamethoxazole to eliminate the remaining bacteria.
At present, there is no such vaccine to prevent glanders whether in humans or animals. But trials on vaccines are ongoing for acute infections.
Glanders is a curable infection only if it is detected at early stages. Once glanders is suspected, isolate all the suspected animals and restrict their movement to avoid transmission. Always seek veterinarian, maintain hygienic measures and prefer laboratory work to confirm the diagnosis. Never try to treat it without confirmation as it can affect humans. When glanders is confirmed, notify the authorities, go for treatment with combination of antimicrobials, if it is at early stages otherwise cull the animal.
Glanders is a serious public health risk because of its zoonotic potential, contagious transmission and severe clinical effects. Thus, it remains an important global concern mainly in Asia and Middle East.