Protect yourself. A deadly and highly contagious human strain of tuberculosis (Mycobacterium tuberculosis or TB) is infecting and killing captive elephants. The National Institute for Occupational Safety and Health has determined that USDA veterinary medical officers and animal care inspectors who conduct elephant inspections may be at risk for TB infection. TB transmission involving M. tuberculosisfrom infected elephants to humans has been reported between zoological workers and other animal handlers. TB infection of USDA Animal and Plant Health Inspection Services personnel has been reported, although inadequate reporting procedures failed to identify the source of transmission. TB transmission from elephants to members of the public has never been studied.
TB is airborne and spreads through tiny droplets in the air. According to Dr. John Lewis of the International Zoo Veterinary Group, “[I]f tuberculosis is diagnosed in an elephant there are clear public health implications as the disease can be spread by close contact with infected animals [and] people.” Circuses routinely allow members of the public to feed, pet, and ride elephants.
Elephants in circuses are predisposed to tuberculosis because of routine transport that may expose them to other infected elephants and because of stress factors, including severe punishment, extreme confinement, inconsistent water quality and food supply, and poor nutrition.
Infected elephants may exhibit no symptoms of TB or may suffer from chronic weight loss, diminished appetite, chronic nasal discharge, coughing, and intolerance to exercise.
TB is difficult to identify in elephants. Elephants are too large to be x-rayed, skin tests are unreliable, and trunk wash cultures only indicate whether the elephant has active TB. No test can determine if an elephant is harboring a TB infection. Circuses may also intentionally mislabel trunk wash specimens from infected animals, using a TB negative animal as the donor. Most circuses have been cited by the USDA for failure to comply with TB testing requirements for elephants and handlers.