title: Molecular characterisation and genetic variation of Elephant Endotheliotropic Herpesvirus infection in captive young Asian elephants in Thailand.
abstract: Elephant Endotheliotropic Herpesvirus (EEHV) is emerging as a new threat for elephant conservation, since being identified as the cause of severe, often fatal, haemorrhagic disease in young Asian elephants. To describe positive cases and the molecular relatedness of virus detected in elephants in Thailand, we re-examined all available of EEHV samples occurring in young elephants in Thailand between 2006 and 2014 (n=24). Results indicated 75% (18/24) of suspected cases were positive for EEHV by semi-nested PCR. Further gene analysis identified these positive cases as EEHV1A (72%, 13/18 cases), EEHV1B (11%, 2/18) and EEHV4 (17%, 3/18). This study is the first to phylogenetically analyse and provide an overview of most of the known EEHV cases that have occurred in Thailand. Positive individuals ranged in age from one to nine years, with no sex association detected, and occurred across geographical locations throughout the country. All individuals, except one, were captive-born. No history of direct contact among the cases was recorded, and this together with the fact that various subtype clusters of virus were found, implied that none of the positive cases were epidemiologically related. These results concur with the hypothesis that EEHV1 is likely to be an ancient endogenous pathogen in Asian elephants. It is recommended that active surveillance and routine monitoring for EEHV should be undertaken in all elephant range countries, to gain a better understanding of the epidemiology, transmission and prevention of this disease.
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia; Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand. Electronic address: ssripiboon@gmail.com.
authors: Supaphen
authors: S
authors: Sripiboon
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia.
authors: Bethany
authors: B
authors: Jackson
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia.
authors: William
authors: W
authors: Ditcham
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia.
authors: Carly
authors: C
authors: Holyoake
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia.
authors: Ian
authors: I
authors: Robertson
authors: Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; Center of Excellence in Elephant Research and Education, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand.
authors: Chatchote
authors: C
authors: Thitaram
authors: Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand.
authors: Pallop
authors: P
authors: Tankaew
authors: Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
authors: Preeda
authors: P
authors: Letwatcharasarakul
authors: College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, Australia.
authors: Kristin
authors: K
authors: Warren
mesh_terms: D000820:Animal Diseases / Q000821:virology*; D000818:Animals; D004606:Elephants / Q000821:virology*; D005260:Female; D005814:Genes, Viral; D014644:Genetic Variation; D005838:Genotype; D006564:Herpesviridae / Q000145:classification / Q000235:genetics*; D006566:Herpesviridae Infections / Q000453:epidemiology / Q000821:virology*; D008297:Male; D010802:Phylogeny; D013785:Thailand / Q000453:epidemiology
keywords: EEHV; Elephant; Elephas maximus; Herpesvirus; Thailand