SELECTED INSTANCES OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS SHEDDING IN TRUNK SECRETIONS BY AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN COMPARISON TO SHEDDING BY ASIAN ELEPHANTS (ELEPHAS MAXIMUS).

Abstract

This study examined the viral shedding kinetics of elephant endotheliotropic herpesvirus (EEHV) in African elephants (Loxodonta africana) compared to viral shedding behavior in Asian elephants (Elephas maximus). Little is known about the transmission dynamics and epidemiology of this disease in African elephants. In light of recent clinical cases and mortalities, this paper aims to identify trends in viral biology. Trunk wash samples were collected from 22 African elephants from four North American zoological institutions that had recently experienced herd viremias or translocations. Processing of these samples included DNA extraction followed by qPCR to quantitate viral DNA load. The results were then compared with available literature that chronicled similar cases in Asian and African elephants. Minimal EEHV shedding was detected in response to varied herd translocations. Increased shedding was recorded in herds in which an elephant experienced an EEHV viremia when compared to baseline shedding. These index infections were followed by subsequent viremias in other elephants, although it is not known if these were recrudescence, transient controlled viremias, and/or primary infections via transmission to other elephants. When compared to historically published data, it was observed that EEHV3 cases in African elephants and EEHV1A cases in Asian elephants had consistently higher levels of viral DNA in the blood than were shed in trunk secretions, a fact that is seemingly inconsistent with such severe cases of disease and the high mortality rates associated with those respective types. The findings produced in this study highlight the need for more routine monitoring of viral shedding in African elephant herds to elucidate possible EEHV transmission and recrudescence factors for ex situ population management.