An outbreak of anthrax occurred in captive African lions (Panthera leo) on a wildlife sanctuary after they were fed beef from a carcass condemned at slaughter. Out of 9 lions at the Sanctuary, six (66.7%) developed illness typical of Bacillus. anthracis infection 48 hours post-consumption. The infection was confirmed by identification of the bacillus on methylene polychrome blue stained thin blood smears (MacFadyean reaction) at the Central Veterinary Laboratory, Department of Veterinary Services, Harare,. Zimbabwe. Three other exposed animals did not develop signs of the infection. All sick animals were treated with a single intramuscular injection of penicillin-streptomycin. However, one lion died shortly after treatment. Affected lions exhibited oedema and swelling of face and neck, while two others developed cellulitis and excoriation of the facial skin. Infected animals recovered 6-8 weeks after the onset of the disease. There were no reports of anthrax in the herd of origin of the infected cow, nor subsequently in humans who handled the carcass at the abattoir and animal sanctuary. This incident showed that anthrax may occur with high morbidity but low mortality rates in African lions exposed through consumption of infected meat. Undetected cases of anthrax in incubating phase in slaughter livestock pose disease risks for captive carnivores, pets and humans who may be fed unsuspected meat and offal. The need for heightened vigilance in ante mortem screening of slaughter animals for diseases cannot be over-emphasized.
Keywords: African lion, anthrax, zoonosis, risk, abattoir