Understanding and quantifying the effect of the density of wild ungulates as a determinant of emerging multi-host pathogens under a Global Health perspective

  • Funding: MINECO (Ministry of Economy and Competitiveness)
  • Leader: Jesse Barandika
  • Implementation: 2017-2020

The geographical and, above all, demographic expansion of wild ungulates is one of the most important recent changes in the agro-silvo-pastoral systems of the northern hemisphere. The explosion of species such as wild boar (Sus scrofa) or deer (Cervus elaphus) has consequences for biodiversity conservation, agriculture, livestock farming and health. Demographic changes in host populations benefit highly relevant multi-host pathogens, which thrive on finding hosts that are not subject to controls, which act as reservoirs. In addition, the increase in interactions between livestock, wildlife and humans creates new opportunities for the maintenance and emergence of shared pathogens.

Since 1980, Spanish wild boar populations have increased tenfold. High densities of deer locally also show increasing trends. In this context, the health and sustainability of extensive livestock farming is increasingly compromised by pathogens shared with the wildlife, some of which are also of great relevance to the health of humans. Controlling shared infections requires in-depth knowledge of the determinants of infection in multi-host contexts, as well as the population dynamics of hosts, vectors and pathogens.

This proposal is based on the hypothesis that demographic changes in wild ungulates modulate the dynamics of pathogens shared with livestock and humans, resulting in changes in vector density and the prevalence of pathogens. Understanding and modelling the underlying general patterns will make it possible to identify the targets on which to intervene in the future. The pathogens selected as models in this project are the Crimean-Congo haemorrhagic fever virus, its Hyalomma lusitanicum vector and the mycobacteria of the M. tuberculosis complex.

Wild ungulates play an important role in the epidemiology of these three organisms. In order to test this hypothesis, the general objective of the project is to understand and model the effect of ungulate densities on vectors and pathogens.

General objective:

To understand and model the effect of ungulate densities on vectors and pathogens

Specific objectives:

  1. To develop innovative methods for the integrated monitoring of the dynamics of ungulates and vectors
  2. To understand the link between the density of ungulates, vectors and pathogens at different spatial and temporal scales
  3. To model the host-vector and host-pathogen dynamics to deduce general patterns and evaluate the effect of eventual management interventions on vector density and the prevalence of pathogens.