Use of immunostimulants in the successful treatment of a clinical EEHV1A infection in an Asian elephant (Elephas maximus)

Elephant endotheliotropic herpesvirus haemorrhagic disease (EEHV-HD) poses a significant threat to the captive population of juvenile Asian elephants (Elephas maximus) and also affects elephants in the wild. In human and veterinary medicine, increasing attention is returning to the interferon system, a crucial mediator in the immune response for control of infection. We describe the first reported use of the Zelnate DNA immunostimulant and recombinant human interferon alpha (rhIFNα) as additional medications in the successful treatment of a case of EEHV1A-HD in a juvenile Asian elephant at a UK zoo. Despite an exponential rise in viraemia to a peak of 2.82×106 viral genomic equivalents/ml, only mild clinical signs developed and the calf survived with no adverse effects attributed to the novel treatments. This case is compared with a previous fatal case within the same herd where Zelnate and rhIFNα were not given.