Trypanosoma Evansi Infections in Himalayan Black Bears (Selenarctos Thibetanus)

Abstract

The Asiatic or Himalayan black bear (Selenarctos thibetanus) is an endangered species. In South Asian countries, captive tamed Himalayan bears are commonly used by roving bear-charmers to entertain the people in rural and urban areas. In captivity, this species confronts several psychophysical traumas and communicable diseases, which are prevalent in other domestic species. The present report describes four cases of Trypanosoma evansi infection in live Himalayan charming bears, which originated from the Faisalabad and Jhang districts of Pakistan. The condition was characterized by pyrexia, accelerated pulse, tachypnea, depression, anemic mucous membranes, and ataxia (n = 3). Microscopic examination of peripheral blood films revealed moderate (n = 2) or high (n = 2) numbers of T. evansi. All four bears were treated twice at 3-day intervals with suramin sodium by using almost twice the dosage recommended for common domestic animals (10 mg/kg). The treated bears were found aparasitemic on repeat blood testing on days 5, 7, and 10 post-treatment. No adverse effects were noted and all four cases recovered in 3-7 days after completion of the second round of treatment. One bear died 8 days after the second treatment (day 11). This is the first report of T. evansi in bears.

Prevalence and molecular diagnosis of Trypanosoma evansi in Nili-Ravi buffalo (Bubalus bubalis) in different districts of Punjab (Pakistan)

“…Several studies in Pakistan revealed that T. evansi is endemic in horses, camels, and bears (Murtaz et al 2006;Muhammad et al 2007). Throughout the country, there has been no reported case of buffalo being infested with this parasite.…”

Trypanosoma evansiand Surra: A Review and Perspectives on Origin, History, Distribution, Taxonomy, Morphology, Hosts, and Pathogenic Effects

“…T. evansi has been found in leopards ( Panthera pardus ), jaguars, ( Panthera onca ), and tigers ( Panthera tigris ) in India [91–93]. T. evansi was recently observed in Asian rhinoceros ( Dicerorhinus sumatrensis sumatrensis ) in Malaysia [94] and in the Himalayan black bear ( Selenarctos thibetanus) [95]. It has even been reported in chickens, but this single observation needs to be confirmed [96]; however the experimental infection of chicks has been demonstrated for a long time [48] and that of young pigeons more recently [97].…”

“…Trypanosoma evansi was observed in 4 natural infections in Himalayan charming bears, in Pakistan; the animals exhibited pyrexia, accelerated pulse, tachypnea, depression, anaemic mucous membranes, and ataxia [95]. …”

Loop-mediated Isothermal Amplification (LAMP) test for detection of Trypanosoma evansi strain B

“…Outbreaks have been recorded for the first time in the endangered Himalayan bear (Muhammad et al, 2007), a farm in metropolitan France (Desquesnes et al, 2008) and in mainland Spain (Tamarit et al, 2009). This phenomenon can be expected to increase with the prevailing global climatic changes that may gradually lead to increases in arthropod vectors and vector borne diseases.…”