Oregon Zoo Suspends TB Treatments for Packy

The Oregon Zoo is suspending tuberculosis treatments for Packy, their beloved elephant who, at 54 is the oldest of his species on the continent and one of the oldest in the world. Zoo officials are consulting with outside experts as they consider the next steps.

Packy was diagnosed in December 2013. When he was born in 1962, he was the first elephant born in the Western Hemisphere in 44 years.

In September, the zoo's animal-care staff received the results from Packy's monthly trunk-wash culture. The tests were positive - they were the positive results since he was first diagnosed. The return of the disease also means that he has to be kept separate from the rest of the herd.

"We had been feeling increasingly optimistic about Packy's treatment regimen, and he had been tolerating it well, so this recent result was disappointing," said Dr. Tim Storms, the zoo’s senior veterinarian.

Until that point, staff had believed medications were helping keep the tuberculosis at bay.

The zoo says that follow-up tests presented staff with an additional hurdle: testing showed Packy's particular strain of TB was resistant to two classes of antibiotics — rifampin, which had been a primary component of his treatment regimen, and quinolones.

"Without those options, we're very limited in our ability to treat this infection," Storms said. "We've stopped Packy's treatment for the time being, since we now know that it’s been ineffective. We’re consulting with veterinarians and pharmacologists around the country, considering what to do next."

Managing TB in Asian elephants can be difficult since little is known about treating the disease outside of humans, according to Dr. Storms. In recent years, the zoo has successfully treated two elephants, Rama and Tusko, adding to the collective knowledge about diagnostics and care.

Packy's care, though, has been more challenging due to his advanced age, unpredictable musth cycles, reluctance to accept oral medications, and intolerance for isoniazid, one of the essential first-line TB medications.

Before embarking on the most recent regimen, veterinarians made several attempts to treat Packy with isoniazid, administering this preferred treatment option in combination with other medications. Despite adjustments in dosage levels and delivery methods, treatment had to be stopped due to side effects such as appetite loss and elevated liver enzymes.

After receiving the latest test results, Dr. Storms informed public health authorities, who confirmed that the zoo’s current human safety protocols are effective and should remain in place.

"We've continued to work closely with the zoo," said Dr. Jennifer Vines, deputy health officer for Multnomah County. "They've been very careful about making sure visitors, volunteers and staff are safe."

The zoo has also exercised an abundance of caution to ensure the health of its other elephants, Dr. Storms said. A year of continuous treatment would be required before Packy could share the same space with other elephants or come within 100 feet of the public. Unfortunately, the inability to treat him for that duration means it’s still not easy for Packy's fans to see him.

"You can catch glimpses of him from time to time in the southernmost yard, which is to the right as you’re walking along the pathway into Forest Hall," said elephant curator Bob Lee, who has cared for Packy for 16 years. "And we'll continue to share photos and videos whenever we can."

Lee has worked with Packy since coming to the Oregon Zoo in 1999.

"You can be tired, dragging, and come in in the morning and he looks at you with big eyes," Lee tells Patch. "There is not a cup of coffee in the world that will motivate you like he does."

In his years at the zoo, Packy has sired seven calves - two of whom are still alive. Sung-Surin or Shine, was born to Packy and Pet on December 26, 1982 and still lives at the zoo. Khun-Chorn, a male, was born to Packy and Me-Tu on May 19,1979 and currently lives at the Dickerson Park Zoo.

The Oregon Zoo is recognized worldwide for its Asian elephant program, which has spanned more than 60 years. Considered highly endangered in their range countries, Asian elephants are threatened by habitat loss, conflict with humans and disease. It is estimated that just 40,000 to 50,000 elephants remain in fragmented populations from India to Borneo.

Photo and video courtesy Oregon Zoo