CONTEXT

There is a growing understanding that human and animal health are inextricably linked and inter-dependent. The extended and complex wildlife/livestock/human interfaces occurring by definition within transfrontier conservation areas (TFCAs) are prone to inter-species pathogen transmission, maintenance and sometimes emergence. This is attributable to the inevitable sharing of the same ecological systems as competition for the available resources increases. These hotspots for pathogen dynamics require specific management and control options. Currently, these options are unknown or inefficient in TFCAs and the health issues have strong sanitary, economic, ecological and socio-cultural implications which could compromise their successes. Therefore, it is imperative that the options for management and control of health issues in these hotspots be informed by scientific research.

The "Health & Environment" theme is organised around three themes:

• Managing zoonoses with the development of the "One Health" approach
• Understanding pathogen and disease ecology in multi-hosts systems at wildlife/livestock interface
• Promoting animal production in TFCAs through sustainable management of diseases of local and national economic importance.

The “One health” concept in TFCAs: targeting zoonoses

Research studies on zoonoses within the RP-PCP began with bovine tuberculosis (bTB) and brucellosis. Investigations of the role of the African buffalo in disease maintenance and spread at wildlife/livestock/human interfaces are on-going in the Great Limpopo (GL) and Kavango-Zambezi (KAZA) TFCA. Notably, the risk of transmission of bTB and brucellosis from wild and domestic animals to human has been the focus of an MPhil study. These activities will likely expand to include more zoonotic diseases such as trichinellosis and cysticercosis in indigenous breeds of pigs in rural areas and wild pigs; Rift Valley Fever (RVF) in ruminants; and rabies in domestic dogs, jackals and mangooses. Trypanosomosis and tick-borne diseases (TBD) represent also a good model of vector borne diseases with both animal and human concerns. Concerning bTB and brucellosis, exploration of the role of other wildlife reservoirs other than the buffaloes could be of interest.

An important point for the theme is to strengthen the relationship between academic research and Veterinary Services in order to address relevant research questions that are of field relevance. Regular consultation and feedback with small-scale farmers in TFCAs willhelp us to keep focus on relevant matter with applied implications. The collaboration with the Human Health services especially with regard to conducting joint research and sharing and dissemination of information is one of the future priority in the development of the “One Health” approach.

The construction of a network on epidemio-vigilance involving from the onset all health (human and animal) professionals as well as academic staff side began on the HE leaders’ instigation but it still has to be formalized.

From a methodological point of view, there are numerous approaches on risk factors for release of pathogens into the human food chain, but it will also be important to develop the analysis of risk factors from the exposure point of view. We need to develop molecular epidemiology for instance for (eg of bTB, brucellosis and ticks and TBD to assess the spill over from one species to the other. In this regard, there is also a need for building collaborative research and fund-raising initiatives with regional Universities and institutions focusing on developing local competences and capacity..

The analysis of the commodity (as well as value) chain linked with zoonotic foodborne diseases using tools such as HACCP and risk analysis will permit to integerate all stakeholders involved in animal and human health.

Understanding of pathogen dynamics in relation to wildlife/domestic interactions

The dynamics of pathogens at complex wildlife/domestic interfaces is not yet well understood. Their spill over from one host to the next, their maintenance, spatial spread or emergence in new host populations are influenced by environmental, ecological and anthropological factors acting concomitantly. However, in order to manage and control these pathogen dynamics in multi-hosts systems, these epidemiological processes need to be understood.

Using mainly the buffalo/cattle model in the GLTFCA and KAZA TFCA, interdisciplinary studies try to disetangle the various factors triggering infectious contacts between these two hosts. Telemetry, geography, genetic and social studies complement more classical epidemiological studies to estimate where, when and how often do infectious contacts occur and who is involved. A specific attention is given to the relationship between ecological and epidemiological contacts (i.e. infectious contact) in relation to modes of pathogen transmission such as direct or environmental transmission.

These studies have implications in terms of behavioural ecology of host, disease ecology and biodiversity conservation.

Diseases of economic importance

This theme of the Health and Environment petal will help strengthen the collaboration between Veterinary Science, Animal Science and Agricultural economics. Through the development of project proposals looking at the economic impact assessment of diseases of economic importance such as TBD, FMD and abortion syndromes in addition to their strategies and policies for control will create some links also with social and political sciences to develop some transdisciplinary approaches.

The epidemiology and risk factors for TBD, tick-associated diseases and pathogens should be of interest for the theme, but questions relating to the real spread of these diseases/vectors Remain unanswered. Similarly, the role of drivers such as resettlement, animal movement, climate change involved among others have not been explored for these diseases/vectors

Abortion syndromes in domestic ruminants (cattle, sheep and goats) are among the major causes of economic loss especially in resource-poor livestock owners living at the edges of TFCAs. These abortion syndromes may be attributable to infectious causes such as brucellosis, leptospirosis, RVF, Campylobacteriosis, neosporosis among others, but there is lack information about the exact causes, for proper management and control. Furthermore, the various risk factors for exposure to the pathogens in these TFCAs have not been elucidated. One of the research thrusts for the Health and Environment petal is to introduce the cross-cutting dimension especially through studying the economic impact of these diseases by linking veterinarians, animal scientist, agricultural economists and social scientists.