In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) housed at the Nashville Zoo. Over a period of several days, all 11 adult animals with an age range of 1.75 to 6.5 years were affected, while the one nursing neonate appeared unaffected. Clinical signs included nasal discharge and congestion, lethargy, and inappetence with severity ranging from mild to severe.
Diagnostics included nasal swabs submitted to the Clinical Virology laboratory at the University of Tennessee College of Veterinary Medicine. The samples were prepared and inoculated onto cell cultures with cytopathic effect noted on first passage. Characterization of the virus isolate was consistent with influenza virus of the Orthomyxoviridae. Further testing identified the pathogen as influenza A H1N1, a human subtype. This was the first known occurrence of influenza documented in giant anteaters.
These anteaters were housed in an off-exhibit facility with no exposure to the public, other collection animals, nor native wildlife. Despite increased vigilance, no other collection animals were noted to have respiratory disease during this period. Many zookeepers, including the anteater keepers, were ill with respiratory disease preceding and during this outbreak in the anteater colony. It was concluded that the keepers were the most likely source of the virus affecting the anteater colony.