Fatal disease strikes Calgary Zoo's elephant calf

Malti, the elephant calf born at the Calgary Zoo a year ago, has been diagnosed with a fatal disease that attacks the circulatory system, zoo officials said Friday.

The Asian elephant is suffering from elephant herpesvirus, a disease that leads to internal bleeding that can overwhelm the heart.

"There is no doubt that this is a very critical situation,"the zoo's veterinarians said in a news release.

They said they began treating Malti with anti-viral medication when she developed mild symptoms on Monday, but they acknowledged the prognosis is not good.

Only four elephants have survived elephant herpesvirus with early treatment. The virus has been known to kill animals within a week of infection.

This form of thedisease, which was identified by U.S. researchers in 1999, is responsible for the deaths of nearly a dozen young elephants in North American zoos over the past 20 years.

There is no evidence of transfer of the virus to people or to other non-elephant species. There is minimal risk to the four adult elephants in the herd, the the zoo said.

In May, 41 of 43 stingrays at the zoo's touch-tank mysteriously died. Various tests could not determine their cause of death.

In November 2007, a hippo died after a 29-hour road tripto the Calgary Zoo from the Denver Zooin a climate-controlled truck . It's believedthe animallaid in one position in her crate for too long, damaging muscles that released toxins into her system.