Elephant virus has zoos worried

ST. LOUIS -- A virus that is endangering the life of a 2-year-old elephant at the St. Louis Zoo has mystified scientists for years.

The virus, a herpes infection that can cause extensive internal bleeding, hits only elephants and seems to target the young. It's killed one in five elephant calves born in the U.S. since 2000, according to the Association of Zoos and Aquariums.

Scientists don't know how it's spread and there is no proven cure.

"It is probably one of the biggest problems that zoos are dealing with right now" with their elephant populations, Mike Crocker, superintendent of Dickerson Park Zoo in Springfield, told the St. Louis Post-Dispatch.

Three elephants at Dickerson have died from the virus, most recently one in 2007. A fourth elephant died shortly after moving to a California zoo. But Dickerson also is home to one of the rare survivors of the virus, Chandra, who was treated successfully with antiviral drugs in 1997.

Now, the elephant Jade is fighting the virus at the St. Louis Zoo, after being diagnosed Tuesday. She's the first case at the St. Louis Zoo, which has eight elephants.

The zoo started treatment the day before the diagnosis because Jade's behavior had already changed, said assistant general curator Bill Houston.

Behavioral changes are often the sole outward symptom of the disease and it can be detected by tests only after it's appeared. Then it is a race against the clock.

"All we know about the illness is that the sooner you jump on it, the better chance you have of solving it," Houston said.

Jade, who is being kept from public view, was in stable condition on Friday, according to the zoo's website. A call from The Associated Press on Saturday was not returned.

The virus typically runs its course in about a week.

Researchers identified the virus in 1995 while investigating the death of a 16-month-old elephant at the National Zoo in Washington. One of the co-discoverers was Dr. Laura Richman, who oversees the National Elephant Herpesvirus Laboratory.

Richman said scientists still do not understand why some elephants don't have any symptoms from the virus while others lose their lives. Asian elephants appear more susceptible than African ones and the virus is found in both wild and captive animals, she said.

But a California-based zoo watchdog group, In Defense of Animals, contends that herpes cases in elephants illustrates some of the problem with keeping elephants in captivity.

Researchers and zoo officials across the country are watching Jade's case.

"If we're going to provide a hedge against Asian elephant extinction," said Steve Feldman, spokesman for the Association of Zoos and Aquariums, "we're going to have to solve this problem."