In this context, we have developed VirHostNet (Virus-Host Network), a public knowledge-based system specialized in the management, analysis and integration of virus-virus, virus-host and host-host interactions as well as their functional annotations in the cell. Based on an extensive scientific literature expertise, VirHostNet provides a high-confidence resource of manually curated interactions defined for a wide range of viral species. The content of this high-confidence dataset has been illustrated by the analysis of cellular functions and pathways enriched in proteins targeted by one or many viruses. An integrated cellular network has also been reconstructed from public data and combined with viral data to provide the first draft of the infected cellular network. In addition, an original Web interface has been developed, which provides multi-criteria query and visualization tools for infection network navigation. The utility of the visualisator has been exemplified by network representation of the mTOR pathway and its interplay with viruses.