TB in elephants called 'a gray area'
Animal-rights group says elephant with positive TB test is a danger, but circus and government health officials say there is no risk
Elephants participate in the annual pachyderm parade marking the arrival of Ringling Bros. and Barnum & Bailey Circus to Baltimore March 28. Karen the elephant recently tested positive for tuberculosis, but a follow-up test was negative. (Gene Sweeney Jr., Baltimore Sun / March 28, 2011) By Laura Vozzella, The Baltimore Sun April 6, 2011 An animal-rights group contends that an elephant performing in Baltimore with the Ringling Bros. and Barnum & Bailey Circus poses a health risk to the public because she has tested positive for tuberculosis, but circus and government health officials say the animal is no threat because she does not have an active form of the infectious disease. Karen, a 42-year-old Asian elephant, tested positive for TB in a blood test but negative in a follow-up test known as a trunk wash, which involves taking a culture of saline solution run through the animal's trunk. The positive blood test was enough to get Karen barred from entering Tennessee with the rest of the circus back in December. But it appears that health officials in that state, where TB was transmitted from another elephant to nine employees at a refuge in 2009, were taking a stricter stance than required by the U.S. Department of Agriculture, which calls for quarantining elephants only if they have an active case of TB. Elephant-to-human transmission of TB is a very new field of study — that it occurs at all was only officially established in 2009 by a Centers for Disease Control and Prevention study, prompted by the outbreak at the Tennessee refuge — and experts are still trying to determine the best way to deal with the problem, said Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University School of Medicine and one of the authors of the CDC study. "This is a large gray area," Schaffner said, borrowing a line from one of his co-authors, Rendi Murphree, an epidemic intelligence service officer at the CDC and a visiting scholar at Vanderbilt. The USDA is holding a meeting in Kansas City this very week to discuss the matter. "Could an elephant have a positive MAPIA [blood] test and a negative trunk wash and still be infectious? Is that possible?" Schaffner said. "That's where the current scientific discussion lies. How reliable is a negative trunk wash test? That is a legitimate area of discussion. There are people that say every elephant with a positive MAPIA should be held back under infection control precautions — quarantined, if you will — and treated. Others say it's not necessary." Even given all the unknowns, Schaffner thinks that there is little risk of a spectator at the circus becoming infected from an elephant. "If you're at a circus, you're at a great distance from the elephants," he said. "You do not have genuinely prolonged contact with them. You're there for two hours of the show. That sort of exposure should not put people at risk." He added: "I would let my grandchildren attend."read more at:http://www.baltimoresun.com/entertainment/bs-ae-elephant-tuberculosis-20110406,0,6958500.story?track=rss