ST. LOUIS • The St. Louis Zoo says it's a mystery how 40-year-old Asian elephant Donna contracted tuberculosis. No other elephant or keeper has tested positive for the illness.
"We assume elephants get TB like any other animal," said the zoo's director of animal health, Dr. Randy Junge. "An animal or human who has TB blows it out and another animal can pick it up. It takes prolonged contact. But we have a closed herd with no animals coming or going."
Junge said Donna has not lost weight, the most obvious symptom tuberculosis in elephants. He expects Donna to recover. She is taking antibiotics and will live in an off-display yard for the next year.
"Our established protocols have allowed us to detect this early and take steps to get Donna on the road to a full recovery without complications," said Junge. "Our elephant care team has a wonderful rapport with Donna and her herdmates, so she's a very cooperative patient."
Donna will remain with the zoo's other elephants who will be tested frequently for TB. Junge said there is no point separating Donna from the herd now.
"She's been with them all along so they've all been exposed to what she's been exposed to," said Junge. "Because they are social animals, putting her in isolation would be inappropriate. We want her to remain comfortable and for herd life to go on."
Zoo officials say visitors are not at risk.
Another zoo elephant died in 1979 from tuberculosis. More recently, the illness also has surfaced at other zoos and circuses. A government report issued this year blamed a sick elephant for an outbreak among workers at a Tennessee elephant sanctuary in 2009.
"There have been a few cases of TB in elephants since the 1990s, which is why we test for it," said Junge. "Once we became aware elephants can get the human form of tuberculosis, all of the zoos began doing annual cultures for it."
The zoo discovered Donna's condition during routine annual testing. Officials have since notified the Missouri Department of Health, St. Louis Department of Health and U.S. Department of Agriculture. No vaccine exist for tuberculosis.