Elephant Endotheliotropic Herpesvirus 4 and Clostridium perfringens Type C Fatal Co-Infection in an Adult Asian Elephant (Elephas maximus)

Simple Summary Elephant endotheliotropic herpesvirus hemorrhagic disease is a severe and often fatal viral disease in elephants, one of the most significant causes of mortality of juvenile Asian elephants in captivity. The most lethal cases are associated with two types of herpesvirus, EEHV1A and EEHV1B. This case report documents a fatal co-infection of Clostridium perfringens type C and elephant endotheliotropic herpesvirus hemorrhagic disease, caused by EEHV4, in an adult female Asian elephant. This report highlights the importance of having both EEHV-HD and clostridial enterotoxemia as potential differential diagnoses in cases of widespread tissue necrosis and internal hemorrhage in elephants, due to their macroscopic similarities, frequent co-occurrence and severity in captive Asian elephant populations. Elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD) is an acute, often fatal, multisystemic hemorrhagic disease and one of the most significant causes of mortality of Asian elephants in captivity. Most fatal cases of EEHV-HD are associated with EEHV1A and EEHV1B in juveniles. This case report describes the clinical and pathological features of a fatal co-infection of Clostridium perfringens type C and EEHV-HD, caused by EEHV4, in an adult female Asian elephant. Although fatal clostridial enterotoxemia has been occasionally reported in elephants, this report highlights the importance of having both EEHV-HD and clostridial enterotoxemia as potential differential diagnoses in cases of widespread tissue necrosis and internal hemorrhage in elephants, regardless of the animal age group, due to their macroscopic similarities, frequent co-occurrence and cumulative morbid potential.