Comparison of Four Serologic Assays and Culture to Determine Tuberculosis Infection in Captive Elephants in Nepal
American Association of Zoo Veterinarians Conference 2007
Susan K. Mikota1, DVM; Michele Miller2, DVM, PhD; Genevieve Dumonceaux3, DVM; Dr. Kamal Giri4; Dr. Kamal Gairhe5; Karin Hamilton6, DVM; Dr. Sarad Paudel4; Konstantin Lyaschshenko7, PhD; R. Scott Larsen8, DVM, MS, DACZM; Janet Payeur9, DVM, PhD; W. Ray Waters10, DVM, PhD; M.D. Salman11, BMVS, PhD; Gretchen Kaufman6, DVM
1Elephant Care International, Hohenwald, TN, USA; 2Disney’s Animal Kingdom, Lake Buena Vista, FL, USA; 3Busch Gardens, Tampa, FL, USA; 4Institute of Agriculture and Animal Science, Kathmandu, Nepal; 5Chitwan National Park, Sauraha, Chitwan, Nepal; 6Tufts Center for Conservation Medicine, Cummings School of Veterinary Medicine, North Grafton, MA, USA; 7Chembio Diagnostics, Medford, NY, USA; 8Department of Medicine and Epidemiology, School of Veterinary Medicine ,University of California-Davis, Davis, CA, USA; 9USDA, APHIS, VS, NVSL, Ames, IA, USA; 10National Animal Disease Center, Ames, IA, USA; 11Animal Population Health Institute, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
Abstract
Our team conducted the first comprehensive range country elephant tuberculosis (TB) survey in January 2006. This collaboration encompassed the work of Dr. Kamal Giri in fulfillment of his M.V.Sc degree at the Institute of Agriculture and Animal Science; the support of the Department of National Parks and Wildlife Conservation and Tufts Center for Conservation Medicine; and the ongoing Elephant TB Initiative of Elephant Care International.
We examined 120 captive elephants and compared results of four serologic tests: the ElephantTB Stat-Pak®, MultiAntigen Print ImmunoAssay (MAPIA)™, an enzyme-linked immunosorbent assay (ELISA), and immunoblot with culture results from laboratories in Nepal and the United States. A total of 289 culture samples were collected from 119 elephants; blood was collected from 115 elephants. Cultures were processed at the National Tuberculosis Center (Nepal) and the National Veterinary Services Laboratories (United States).
Results of culture at the National Tuberculosis Center (4 positive), ElephantTB Stat-Pak® and MAPIA (6 positive; 9 suspect), ELISA (8 positive; 2 suspect) and immunoblot (0 positive) were evaluated to place elephants into the following categories:
1. High risk: tests suggest or confirm TB
2. Low risk: elephants are test negative or equivocal
3. Undetermined risk: no blood sample obtained
Results suggest an approximate prevalence of 13%, comparable to the prevalence among Asian elephants in the U.S.
As a preliminary management strategy, we recommended segregation of high-risk elephants, repeat testing of elephants with equivocal results, screening all remaining captive elephants in Nepal, and TB screening of all mahouts.
Acknowledgments
The authors gratefully acknowledge the cooperation of the Department of National Parks and Wildlife Conservation, Nepal and support from the Abraham Foundation, the Mazuri Fund, the Walter J. Ernst Memorial Fund, the American Veterinary Medical Foundation, and the Dodge Foundation.