Diagnosis and Medical Management of Pulmonary Acariasis in two Silverback Western Lowland Gorillas (Gorilla gorilla) at Different Zoological Institutions
American Association of Zoo Veterinarians Conference 2019
James G. Johnson III1, DVM, MS, CertAqV, DACZM; Sathya K. Chinnadurai2, DVM, MS, DACZM, DACVAA, DACAW; Gregory E. Holt3, MD, PhD; Marisa Bezjian1, DVM; Gabriella L. Flacke1, DVM, MVSc, PhD; Heather Stockdale Walden4, MS, PhD; Jennifer N. Langan2,5, DVM, DACZM, DECZM (Zoo Health Management); Julie Sheldon2, DVM, MS; Gwen E. Myers1, DVM
1Department of Animal Health, Zoo Miami, Miami, FL, USA; 2Chicago Zoological Society, Brookfield Zoo, Brookfield, IL, USA; 3Department of Internal Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA; 4Department of Comparative, Diagnostic and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 5Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL, USA
Pulmonary acariasis caused by mites in the genus Pneumonyssus has historically been described in Old World monkeys and chimpanzees (Pan troglodytes);1 however, reports of pulmonary acariasis have been scant in recent literature and this condition has not been reported in gorillas in North American zoos. A 25-yr-old male western lowland gorilla (Gorilla gorilla) at Zoo Miami was diagnosed with pulmonary acariasis caused by mites consistent with Pneumonyssus sp. identified using bronchoscopy following a 2-yr history of intermittent coughing since arrival that was not responsive to any specific empirical treatments. The animal was treated with oral ivermectin (Noromectin 1% solution, Norbrook® Inc., Overland Park, KS, USA) 0.2 mg/kg PO every 2 wk administered with prednisolone (PrednisTab 20 mg, LLOYD, Inc., Shenandoah, IA, USA) 0.2 mg/kg PO and clinically improved 2 mo following treatment, but still had intermittent mild residual coughing. A 39-yr-old male western lowland gorilla at the Brookfield Zoo was diagnosed with pulmonary acariasis following a 7-yr history of intermittent coughing that was managed with inhaled steroids and antihistamines. Previous bronchoscopy only showed inflammation, but bronchoscopy 4 yr later revealed mites in the lower respiratory tract. The animal was treated with oral ivermectin (0.2 mg/kg PO) monthly for 2 mo and no mites were seen at recheck bronchoscopy. The life cycle of pulmonary mites in primates is unknown but infection in these gorillas was suspected to be due to spread from other primates (Old World monkeys, chimpanzees) in proximity that may have harbored subclinical infection. This is the first report of pulmonary acariasis in gorillas residing in North America, and this condition should be considered and screened for in apes with chronic coughing.
We thank the animal care and veterinary technician staff at Zoo Miami and Brookfield Zoo for their care of these animals.
1. Strait K, Else JG, Eberhard ML. Chapter 4: Parasitic diseases of nonhuman primates. In: Abee CR, Mansfield K, Tardif S, Morris T, eds. Nonhuman Primates in Biomedical Research. New York (NY): Elsevier; 2012:197–297.