Transmission of foot and mouth disease at the wildlife/livestock interface of the Kruger National Park, South Africa: Can the risk be mitigated?

Abstract

15.2 Highlights  Since 2000, the efficacy of foot and mouth disease control at the interface between cattle and buffaloes at the edge of the Kruger National Park has deteriorated and needs urgent improvement.  This quantitative risk assessment allowing to model the risk of FMD virus transmission between cattle and buffaloes at the edge of the KNP is based on ecological and epidemiological data and fits with past and current numbers of outbreaks.  Including variability and uncertainty this model could be used as a tool for assessing control strategies and may be easily adapted to other transfrontier conservation parks in Southern Africa.  Examples encompassing vaccination coverage (or efficacy), control of buffaloes' population in the park, control of buffaloes escaping the park are presented and discussed.3 SummaryIn Southern Africa, the African buffalo (Syncerus caffer) is the natural reservoir of foot and mouth disease (FMD). Contacts between this species and cattle are responsible for most of the FMD outbreaks in cattle at the edge of protected areas, which generate huge economic losses. During the late 1980's and 90's, the erection of veterinary cordon fences and the regular vaccination of cattle exposed to buffalo contact at the interface of the Kruger National Park (KNP), proved to be efficient to control and prevent FMD outbreaks in South Africa. However, since 2000, the efficiency of those measures has deteriorated, resulting in an increased rate of FMD outbreaks in cattle outside KNP, currently occurring more than once a year. Based on retrospective ecological and epidemiological data, we developed a stochastic quantitative model to assess the annual risk of FMD virus (FMDV) transmission from buffalo to cattle herds present at the KNP interface. The model suggests that good immunization of approximately 75% of the cattle population combined with a reduction of buffalo/cattle contacts is an efficient combination to reduce FMDV transmission to one infective event every 5.5 years, emulating the epidemiological situation observed at the end of the 20 th century, before current failure of control measures. The model also indicates that an increasing number of buffalo present in the KNP and crossing its boundaries, combined with a reduction in the vaccination coverage of cattle herds at the interface, increases 3-fold the risk of transmission (one infective event per year).The model proposed makes biological sense and provides a good representation of current knowledge of FMD ecology and epidemiology in Southern Africa which can be used to discuss with stakeholders on different management options to control FMD at the wildlife livestock interface and updated if new information becomes available. It also suggests that the control of FMD at the KNP interface is becoming increasingly challenging and will probably require alternative approaches to control this disease and its economic impact.

Characterization of Gofa Cattle Population, Production System, Production and Reproduction Performance in Southern Ethiopia

“…Among the disease, Trypanosomiasis ,anthrax and Foot and mouth disease were considered as the most economically important disease ranked first, Second and third with different index values, respectively [10][11][12] (Tables 24-26). …”

Transmission of Foot-and-Mouth Disease SAT2 Viruses at the Wildlife–Livestock Interface of Two Major Transfrontier Conservation Areas in Southern Africa

“…Previous studies of FMDV in the South African Development Community (SADC) attempted to assess the role of African buffalo in the epidemiology of FMDV and its transmission to domestic cattle at the wildlife–livestock interface by different approaches ( Thomson et al, 1992 , 2003 ; Jori et al, 2009 ; Brahmbhatt et al, 2011 ; Miguel et al, 2013 ; Jori and Etter, 2016 ). Although wildlife plays an important role in maintaining FMDV strains and occasional transmission to livestock and other wildlife species occur, some SAT viruses can also be maintained within livestock populations in countries where the disease has become endemic ( Vosloo et al, 2002 , 2009 ).…”

Tracing cross species transmission of Mycobacterium bovis at the wildlife/livestock interface in South Africa

“…The occurrence of wildlife maintenance hosts has complicated the control of the disease especially at the wildlife/livestock/human interface where there is overlapping of territories due to encroachment of human activities into wildlife conservation areas and potential escape of wildlife from these areas [5][6][7][8]. Cross-species transmission of bTB has been documented at the wildlife/livestock interface, with wildlife maintenance hosts such as the African buffalo (Syncerus caffer) in South Africa and the Kafue lechwe antelopes (Kobus leche kafuensis) in Zambia [9][10][11].…”