Affiliation: | a Helminthic Diseases Laboratory, Animal Parasitology Institute, Agricultural Research Service, U.S. Department of Agriculture, Beltsville Agricultural Research Center, Beltsville, MD 20705, U.S.A. b Uniformed Services University of the Health Sciences, Department of Preventive Medicine, 4301 Jones Bridge Road, Bethesda, MD 20814, U.S.A. c Department of Parasitology, National Yangming Medical College, Shih-Pai, Taipei (11221), People's Republic of China |