Integrating ecology and epidemiology using individual-based multi-species networks

Parasite transmission in host communities is a function of ecological factors that influence interspecific contacts and contact patterns within species. These two levels are studied with different kinds of networks – ecological networks and individual contact networks – and the integration of these levels is essential for effective understanding of parasite transmission. We combined these approaches by creating epidemiological networks based on parasite sharing from individual-based ecological host-parasite networks. We compared multi- to single-species networks to investigate the drivers of helminth infection in wild individual rodents of South-east Asia. Network modularity was higher in the multi-species than in the single-species networks. Phylogeny affected affiliation of individuals to modules. The importance of individuals differed between multi- and single-species networks, with species identity and individual traits influencing their position in the networks. Simulations revealed that a novel parasite spreads more slowly in multi- than in single-species networks and that this depended on network structure. Although the relative contribution of within- vs. between-species transmission rates to disease dynamics is important, using multi-host epidemiological networks improves our understanding of parasite dynamics as it further considers interaction structure between individuals.