Network analysis of host–virus communities in bats and rodents reveals determinants of cross-species transmission

Luis, Angela D.; O'Shea, Thomas J.; Hayman, David T. S.; Wood, James L. N.; Cunningham, Andrew A.; Gilbert, Amy T.; Mills, James N.; Webb, Colleen T.

Networks have been used extensively in disease ecology to model the finite and heterogeneous number of social contacts between individuals. Here, we use networks to describe sharing of viruses between different species, rather than individuals. This is akin to other ecological networks, such as food webs, mutualistic, or host-parasite networks (Montoya et al. 2006) . However, we collapse the bipartite network (separate nodes for viruses and host species) to a unipartite projection, weighting contacts between host species by the number of viruses they share. In the same way social networks can highlight the disproportionate importance of specific individuals, such as 'super-spreaders', in population-level disease dynamics, our networks can highlight the importance of certain species in host-virus communities and disease emergence. In addition, we can use other network methods to look at substructures, or 'communities' in the network, highlighting sets of highly interconnected species (Newman 2004) .