Genetic Variant of Elephant Endotheliotropic Herpesvirus Detected from Captive Asian Elephants (Elephas maximus) in Thailand from 2007 to 2013

Abstract

The study was aimed at characterizing elephant endotheliotropic herpesvirus (EEHV) that was detected in captive Asian elephants in Thailand from 2007 to 2013. Six tissue samples of dead elephants and two EDTA blood samples of surviving elephants in Thailand showed clinical signs or had lesions of the viral infection. Samples were extracted for DNA amplification using a PCR technique with strain specific primers based on terminase and DNA polymerase genes. Six samples gave positive amplicons for EEHV1 specific primers and two samples gave positive amplicons for EEHV3/4 specific primers. Nucleotide sequencing analysis was assured for strain identification. Five out of the six samples from EEHV1 PCR were positive for the EEHV1A strain and one sample was positive for the EEHV1B strain. The two samples of EEHV3/4 PCR positive products were revealed to be of the EEHV4 strain based on the sequencing of the partial terminase gene. Three strains of the EEHV including EEHV1A, EEHV1B and EEHV4 have been detected in Asian elephants in Thailand from 2007 to 2013. This study revealed the first EEHV1B isolate that has been detected in a captive Asian elephant in Thailand.