Molecular evidence of Elephant Endotheliotropic Herpes Virus (EEHV) from Maharashtra, India

Abstract

Background: Elephant Endotheliotropic Herpes Virus (EEHV) is a significant disease of elephants and has been reported in captive and free-ranging elephants. The disease considerably impacts conservation efforts due to high mortality rates in juvenile elephants. The case presentation discusses the investigation of elephant calf mortality due to EEHV supplemented with molecular, histopathological, and phylogenetic investigations. Case-presentation: Arjun, a five-year-old Asian elephant (Elephas maximus), was found dead after a brief illness. A post-mortem examination was performed, and samples were collected for histopathology and molecular diagnosis. PCR and sequencing confirmed EEHV 1A. The sequence was similar to sequences of EEHV from Assam, India, and Switzerland. The amino acid alignment revealed four substitutions in the U38 protein, due to which the distinct virus was placed separately at the base of the phylogenetic tree. Conclusion: EEHV is a lethal infection in Asian elephants. Molecular techniques confirmed the classical gross and histopathological lesions. EEHV-1A, confirmed in this case, is considered virulent circulating field strain and sequencing efforts are a must to monitor the virus. Considering the dynamic nature of the virus, the herding nature of the species, its impact on juvenile calves, and the lifelong shedding of the virus from adult carriers, it is required to keenly investigate the prevalence and impact of the disease in free-range and captive elephants.