Diagnosis and Treatment of Babesia odocoilei in Captive Reindeer (Rangifer tarandus tarandus) and Recognition of Three Novel Host Species

Abstract

Two captive reindeer (Rangifer tarandus tarandus) at a New York zoological institution were diagnosed with Babesia odocoilei. Clinical signs consistent with acute babesiosis included fever, hemoglobinuria, and hemolytic anemia. Both episodes were precipitated by stressful events that may have compromised their immunocompetence. The diagnosis was confirmed by visualization of intraerythrocytic parasites on stained blood smears, polymerase chain reaction, and speciation of the Babesia by sequencing a hypervariable region of the 18S rRNA gene. One reindeer died with gross and histopathologic lesions, including pigmentary nephrosis with severe acute tubular degeneration and necrosis secondary to intravascular hemolysis. A second reindeer was successfully treated with supportive care and an antiprotozoal, imidocarb dipropionate (Imizol, 12%, Schering-Plough Animal Health, Union, New Jersey 07083, USA) at 3 mg/kg s.c. or i.m. s.i.d. on days 1, 2, 6, 9, and 21. Two other reindeer in the exhibit tested negative for Babesia by polymerase chain reaction but were treated with imidocarb dipropionate as prophylaxis while final testing results were pending. Additionally, B. odocoilei was identified in three novel asymptomatic host species within the collection: yak (Bos grunniens), muntjac (Muntiacus reevesi), and markhor goat (Caprafalconeri). Due to the high morbidity and mortality associated with acute babesiosis, captive reindeer should receive tick prevention, be tested for subclinical infections in endemic areas, and receive aggressive treatment for acute infections when clinical babesiosis is suspected.

Drosha, DGCR8, and Dicer mRNAs are down-regulated in human cells infected with dengue virus 4, and play a role in viral pathogenesis

“…Aside from a brief focal epidemic at the time, DENV4 infection has not been detected in the country until 2010, when it reemerged in the municipalities of Boa Vista and Cantá in the Roraima State of Brazil (Bartlett et al, 2009). The virus quickly spread to different regions in north, northeast, and southeast Brazil (Nunes et al, 2012).…”

Babesia odocoilei infection in a Saskatchewan elk (Cervus elaphus canadensis) herd

“…Although a few trophozoites will enlarge and become potential gametocytes, most cause non-immune-mediated hemolysis as they are released and invade other uninfected erythrocytes. 4,12 In clinically affected elk, the proportion of infected erythrocytes varies, but has been reported as high as 15-20%. 7 Intra-and extravascular immune-mediated hemolysis, initiated by the host's immune response, is a major contributor to anemia in the host.…”

Babesia odocoilei infection in a North American elk (Cervus elaphus canadensis)

“…Although B. odocoilei has been recently identified in captive reindeers at a New York zoological institution (Bartlett et al 2009), to the authors' knowledge, B. odocoilei infection in North American elk in New York State, USA has not been previously reported.…”

“…odocoilei infection may result in hemolytic anemia and anorexia and may cause significant mortality among freeranging animals. Therefore, captive cervids should receive tick prevention, be tested for subclinical infections in endemic areas, and receive aggressive treatment for acute infections when clinical babesiosis is suspected (Bartlett et al 2009). Furthermore, effective animal management practices including appropriate tick control measures should be implemented to prevent transmission of this tick-borne pathogen to susceptible animals (Schoelkopf et al 2005).…”