Glanders is a serious zoonotic bacterial disease that primarily affects horses, mules and donkeys. Some animals die acutely within a few weeks. Others become chronically infected, and can spread the disease for years before succumbing. Glanders also occurs occasionally in other mammals, including carnivores that eat meat from infected animals. Although cases in humans are uncommon, they can be life threatening and painful. Without antibiotic treatment, the case fatality rate may be as high as 95%.

Glanders was a worldwide problem in equids for several centuries, but this disease was eradicated from most countries by the mid-1900s. Outbreaks are now uncommon and reported from limited geographic areas. In non-endemic regions, cases may be seen in people who work with the causative organism, Burkholderia mallei, in secure laboratories. An infection was reported in a U.S. researcher in 2000. Glanders is also considered to be a serious bioterrorist threat: B. mallei has been weaponized and tested against humans, and it was also used as a biological weapon against military horses in past wars.