Global trends in infectious diseases at the wildlife-livestock interface

Abstract

The role and significance of wildlife-livestock interfaces in disease ecology has largely been neglected, despite recent interest in animals as origins of emerging diseases in humans. Scoping review methods were applied to objectively assess the relative interest by the scientific community in infectious diseases at interfaces between wildlife and livestock, to characterize animal species and regions involved, as well as to identify trends over time. An extensive literature search combining wildlife, livestock, disease, and geographical search terms yielded 78,861 publications, of which 15,998 were included in the analysis. Publications dated from 1912 to 2013 and showed a continuous increasing trend, including a shift from parasitic to viral diseases over time. In particular there was a significant increase in publications on the artiodactyls-cattle and bird-poultry interface after 2002 and 2003, respectively. These trends could be traced to key disease events that stimulated public interest and research funding. Among the top 10 diseases identified by this review, the majority were zoonoses. Prominent wildlife-livestock interfaces resulted largely from interaction between phylogenetically closely related and/or sympatric species. The bird-poultry interface was the most frequently cited wildlife-livestock interface worldwide with other interfaces reflecting regional circumstances. This review provides the most comprehensive overview of research on infectious diseases at the wildlife-livestock interface to date.

Keywords: infectious diseases; scoping review; wildlife–livestock interface; zoonoses.

Fig. 1.

Scoping review flowchart. All search categories (wildlife, livestock, disease, geographic region) were joined by the Boolean expression “AND,” resulting in the intersection used for analysis.

Fig. 2.

Temporal trend of publications on diseases at the wildlife–livestock interface (n = 15,998).

Fig. S1.

Temporal trend in diseases (1912–2013). The area plot depicts the proportion of publications comprising all top 10 diseases in Table 1 (blue) and other diseases not included in top 10 (brown).

Fig. 3.

Prominent wildlife–livestock interfaces reported in scientific literature. Shown are the five most frequently cited wildlife and livestock groups (Dataset S1); only publications with one disease (n = 13,293) were included.

Fig. 4.

Temporal trend of publications on avian influenza (A) and bovine tuberculosis (B) at the wildlife–livestock interface. The number of publications is shown in blue. For comparison, media reports and research funding directed at each disease is shown in purple and brown, respectively. Cor, maximum value of the cross-correlation (and associated time lag) between publication and media coverage/funding.

Fig. 5.

Geographic distribution of disease agents (A) and prominent wildlife–livestock interfaces (B). (A) Size of circles is commensurate with the number of publications obtained for the corresponding continent. (B) Top three reported wildlife–livestock interfaces per continent (shown in pairs); only publications with one disease (n = 13,293) were included.