A 15-year-old elephant at the San Diego Zoo, Inhlonipho, better known as Nipho, died Wednesday after contracting elephant endotheliotropic herpesvirus hemorrhagic disease, or EEHV-HD, the San Diego Zoo Wildlife Alliance announced Saturday. The disease is among the most serious health threats facing elephants, although the virus is widespread among both Asian and African elephants in the wild and under human care. It cannot be transmitted to humans or other wildlife.

Zoo officials said in a Facebook statement that most elephants will contract the virus in their lifetime and many carry it without becoming ill, but Nipho's condition deteriorated at an alarming rate despite efforts by veterinarians. "Nipho's illness came on and progressed unusually fast," the officials said. "Our team began treatment right away, even before a definitive diagnosis, and we are continuing to look closely at his case to understand what happened." They added that they hope the loss will help advance understanding of the disease and ultimately save lives.S1S2

Nipho was born at the San Diego Zoo Safari Park to his mother, Umngani, who remains part of the Elephant Valley herd, and spent his whole life in the alliance's care. He later moved to the San Diego Zoo, where he lived with his half-brother, Tsandzikle, known as Sundzu, and another male elephant, Vus'Musi, known as Musi, in a bachelor herd. The two surviving elephants were given an opportunity to say their final goodbyes.S1S2

The situation has grown more worrying because Sundzu has begun showing symptoms of the same disease. Veterinary teams are working around the clock to treat him with antiviral medications, fluids and elephant plasma infusions in hopes of helping him recover. The zoo did not immediately provide details about Sundzu's prognosis when asked for additional information.S1S2