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About the Authors:
Tetsuya Yanagida
* E-mail: [email protected]
Current address: Laboratory of Veterinary Parasitology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yoshida, Yamaguchi, Japan
Affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
Jean-François Carod
Affiliation: Institut Pasteur de Madagascar, Antananarivo, Madagascar
Yasuhito Sako
Affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
Minoru Nakao
Affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
Eric P. Hoberg
Affiliation: US Department of Agriculture, Agricultural Research Service, US National Parasite Collection, Animal Parasitic Diseases Laboratory, Beltsville, Maryland, United States of America
Akira Ito
Affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
Introduction
The pig tapeworm Taenia solium (Cestoda: Taeniidae) is an etiologic agent of cysticercosis, an important zoonosis and neglected tropical disease, and recently ranked as the most important food-borne parasites on a global scale [1]. The lifecycle of T. solium includes humans as the only definitive hosts and domestic pigs as principal intermediate hosts. Cysticercosis refers to infection of various tissues of swine or humans with cysticerci larvae due to ingestion of eggs released from people harboring adult worms in the intestine. Cysticercosis of the central nervous system (neurocysticercosis or NCC), warrants special attention because it is a major cause of seizures and epilepsy in endemic areas [2] and can be lethal especially in remote areas of developing countries [3]. T. solium is distributed worldwide where local people consume pork without meat inspection. We previously reported that T. solium can be divided into two mitochondrial (mtDNA) genetic linages, Asian and Afro-American which differ in the clinical manifestations of human cysticercosis [4]. Their distributions are geographically disjunct in Asia or Africa and Latin America [4]. It has been postulated that T. solium emerged from Africa with early modern humans and through geographic expansion became distributed initially across Eurasia prior to the advent of agriculture and domestication of swine [5]–[7]. Phylogenetic studies have suggested that divergence of the two lineages occurred in the Pleistocene [4], [6], [8]. Recently, sympatry of both mitochondrial lineages was confirmed in Madagascar [6], [8].
Madagascar is a country known to be hyper-endemic for cysticercosis [9], [10]. Cysticercosis in pigs results in condemnation of carcasses, particularly in heavy infections, and thus constitutes a considerable economic challenge. Understanding the current...