Primate malarias as a model for cross-species parasite transmission

Abstract

Parasites regularly switch into new host species, representing a disease burden and conservation risk to the hosts. The distribution of these parasites also gives insight into characteristics of ecological networks and genetic mechanisms of host-parasite interactions. Some parasites are shared across many species, whereas others tend to be restricted to hosts from a single species. Understanding the mechanisms producing this distribution of host specificity can enable more effective interventions and potentially identify genetic targets for vaccines or therapies. As ecological connections between human and local animal populations increase, the risk to human and wildlife health from novel parasites also increases. Which of these parasites will fizzle out and which have the potential to become widespread in humans? We consider the case of primate malarias, caused by Plasmodium parasites, to investigate the interacting ecological and evolutionary mechanisms that put human and nonhuman primates at risk for infection. Plasmodium host switching from nonhuman primates to humans led to ancient introductions of the most common malaria-causing agents in humans today, and new parasite switching is a growing threat, especially in Asia and South America. Based on a wild host-Plasmodium occurrence database, we highlight geographic areas of concern and potential areas to target further sampling. We also discuss methodological developments that will facilitate clinical and field-based interventions to improve human and wildlife health based on this eco-evolutionary perspective.

Removal from the wild endangers the once widespread long‐tailed macaque

“…Active host seeking by Anopheles balabacensis , a primary P. knowlesi vector has been identified more often near long‐tailed macaque sleeping sites (Brown et al, 2022). The transmission of P. knowlesi is influenced by the abundance and distribution of vectors and hosts in the environments, and the removal of macaques, the natural hosts, likely diminishes a buffer to human infections (Fornace et al, 2019; Scott, 2020; Voinson et al, 2022).…”

Molecular detection and identification of Plasmodium spp. isolated from captive-bred cynomolgus monkeys in Bogor, Indonesia

“…Understanding the diversity and distribution of non-human primate malaria is an important first step in predicting the potential zoonotic risk of non-human primate malaria. Studying this diversity can provide critical insights into our understanding of human malaria, as several human malarial species result from host switching from non-human primates [ 3 ]. The zoonotic spillover of wild primate malaria is an emerging global public health concern.…”