Wild and Domestic Pig Interactions at the Wildlife-Livestock Interface of Murchison Falls National Park, Uganda, and the Potential Association with African Swine Fever Outbreaks.

Esther A Kukielka,Charles Masembe,Ferran Jori,Karl Ståhl,David Chavernac,Erika Chenais,Beatriz Martínez-López

doi:10.3389/fvets.2016.00031

Abstract

Bushpigs (BPs) (Potamochoerus larvatus) and warthogs (WHs) (Phacochoerus africanus), which are widely distributed in Eastern Africa, are likely to cohabitate in the same environment with domestic pigs (DPs), facilitating the transmission of shared pathogens. However, potential interactions between BP, WH, and DP, and the resulting potential circulation of infectious diseases have rarely been investigated in Africa to date. In order to understand the dynamics of such interactions and the potential influence of human behavior and husbandry practices on them, individual interviews (n = 233) and participatory rural appraisals (n = 11) were carried out among Ugandan pig farmers at the edge of Murchison Falls National Park, northern Uganda. In addition, as an example of possible implications of wild and DP interactions, non-linear multivariate analysis (multiple correspondence analyses) was used to investigate the potential association between the aforementioned factors (interactions and human behavior and practices) and farmer reported African swine fever (ASF) outbreaks. No direct interactions between wild pigs (WPs) and DP were reported in our study area. However, indirect interactions were described by 83 (35.6%) of the participants and were identified to be more common at water sources during the dry season. Equally, eight (3.4%) farmers declared exposing their DP to raw hunting leftovers of WPs. The exploratory analysis performed suggested possible associations between the farmer reported ASF outbreaks and indirect interactions, free-range housing systems, dry season, and having a WH burrow less than 3 km from the household. Our study was useful to gather local knowledge and to identify knowledge gaps about potential interactions between wild and DP in this area. This information could be useful to facilitate the design of future observational studies to better understand the potential transmission of pathogens between wild and DPs.

Highlights

During the last few decades, a better understanding of how wildlife–livestock interactions potentially contribute to infectious disease emergence has led to an increase of interest on this topic [1]
We assumed that domestic pigs (DPs) could roam throughout the villages under study [35]; we considered any place where wild pigs (WPs) had been seen – within the village area – as a potential spot for an indirect interaction with DP to happen
BP and WH were often observed in swampy areas (47 and 33% of their sightings, respectively), while WH were frequently observed in savannah-bush areas (49% of its sightings) (Table 2)

Summary

Introduction

During the last few decades, a better understanding of how wildlife–livestock interactions potentially contribute to infectious disease emergence has led to an increase of interest on this topic [1]. Some examples could be tuberculosis infection in South Africa (with buffalo and cattle populations in the spotlight) [7] and foot-and-mouth disease maintenance at the Great Limpopo Transfrontier Conservation Area (buffaloes being the major reservoir of infection) [8,9,10,11]. This potential transmission of diseases at the wildlife–livestock interface can have a huge economic impact due to trade restrictions, losses in animal production, and the need of implementing expensive preventive programs or more drastic control and eradication interventions (i.e., vaccination or culling) [12, 13]. A better understanding of wildlife–livestock interactions is crucial to better comprehend the eco-epidemiology of diverse pathogens affecting both wildlife and livestock and to implement more cost-effective preventive and control strategies [14]

Objectives

Methods

Results

Conclusion