Wildmeat consumption and zoonotic spillover: contextualising disease emergence and policy responses

Abstract

Zoonotic diseases are estimated to constitute 75% of all emerging infectious diseases, of which more than 70% come from wild species. The potential threat of zoonotic spillover from the consumption of wildmeat has been the subject of policy and media attention, especially in the context of the COVID-19 pandemic; however, little is known about the actual conditions that contribute to the risk of spillover and associated disease transmission. In this Review, we compile existing evidence from available literature on the conditions of spillover associated with wildmeat consumption, including the types of wild animal and disease, modes of transmission, and the conditions in which spillover is thought to have occurred. We suggest that stronger understanding of the context of spillover from wildmeat is needed to enable more targeted and effective policy responses that reduce the risk of future pandemics of zoonotic origin. Such interventions could also lead to the avoidance of unintended adverse consequences for human communities that rely on wild produce, including wildmeat, as sources of dietary protein, fat, and micronutrients.

Figure 1

Barriers to the spillover process Barriers occur in reservoir hosts (green), the environment and vectors (blue), and spillover hosts (orange). Adapted from Sokolow and colleagues.

Figure 2

Summary of spillover events Events are reviewed by decade of reporting (A), country of reporting (B), size of resulting outbreak (C), transmission pathway (D), and suspected index case (E).

Figure 3

Wildmeat links to spillover effects Events are listed by method of obtaining wildmeat (A) and suspected wildlife source of disease (B).