Tuberculosis serosurveillance and management practices of captive African elephants (Loxodonta africana) in the Kavango-Zambezi Transfrontier Conservation Area

Transbound Emerg Dis. 2018 Apr;65(2):e344-e354. doi: 10.1111/tbed.12764. Epub 2017 Nov 16.

Abstract

Transfrontier conservation areas represent an international effort to encourage conservation and sustainable development. Their success faces a number of challenges, including disease management in wildlife, livestock and humans. Tuberculosis (TB) affects humans and a multitude of non-human animal species and is of particular concern in sub-Saharan Africa. The Kavango-Zambezi Transfrontier Conservation Area encompasses five countries, including Zimbabwe, and is home to the largest contiguous population of free-ranging elephants in Africa. Elephants are known to be susceptible to TB; thus, understanding TB status, exposure and transmission risks to and from elephants in this area is of interest for both conservation and human health. To assess risk factors for TB seroprevalence, a questionnaire was used to collect data regarding elephant management at four ecotourism facilities offering elephant-back tourist rides in the Victoria Falls area of Zimbabwe. Thirty-five working African elephants were screened for Mycobacterium tuberculosis complex antibodies using the ElephantTB Stat-Pak and the DPP VetTB Assay for elephants. Six of 35 elephants (17.1%) were seropositive. The risk factor most important for seropositive status was time in captivity. This is the first study to assess TB seroprevalence and risk factors in working African elephants in their home range. Our findings will provide a foundation to develop guidelines to protect the health of captive and free-ranging elephants in the southern African context, as well as elephant handlers through simple interventions. Minimizing exposure through shared feed with other wildlife, routine TB testing of elephant handlers and regular serological screening of elephants are recommended as preventive measures.

Keywords: African elephant; Mycobacterium tuberculosis; elephant handlers; human-wildlife disease interface; transfrontier conservation areas; tuberculosis diagnosis.

MeSH terms

  • Africa
  • Animals
  • Animals, Wild
  • Antibodies, Bacterial / blood
  • Antigens, Bacterial / blood
  • Conservation of Natural Resources
  • Elephants / microbiology*
  • Female
  • Male
  • Mycobacterium tuberculosis / immunology
  • Mycobacterium tuberculosis / isolation & purification*
  • Risk Factors
  • Seroepidemiologic Studies
  • Tuberculosis / epidemiology
  • Tuberculosis / veterinary*

Substances

  • Antibodies, Bacterial
  • Antigens, Bacterial