Data from: Forecasting potential emergence of zoonotic diseases in Southeast Asia: network analysis identifies key rodent hosts

1. Within complex ecological systems, identifying animal species likely to play a key role in the emergence of infectious zoonotic diseases remains a major challenge. One approach consists of using information on current ecological and parasitological similarities among host species in order to predict the most likely pathways for future pathogen spillover.

2. Using field data acquired from 15 sympatric rodent species in various habitats in Thailand, Cambodia and Laos, we built networks based on shared parasites (17 helminth and 15 microparasite species) and shared habitats among rodent species and humans. We investigated the architectures of bipartite and unipartite networks using modularity, subgroups partitioning or node centrality, to assess the relative epidemiological importance of particular rodent species.

3. Our results showed that Rattus tanezumi, Bandicota savilei and R. exulans were consistently found to be members of subgroups that included humans in unipartite and bipartite networks on zoonotic agents and shared habitats. High values of centrality in shared zoonotic agents were found for the same three rodent species, whereas high values of shared habitats were observed for two of them. Although phylogenetically related rodent species likely shared both habitats and parasites, a lack of habitat specialisation was associated with increased zoonotic parasite sharing.

4. Our results emphasize the disproportionate importance of these three rodent species, through their high degree of connectivity with humans, which may represent a high risk for direct zoonotic spillover. Moreover, due to its high centrality in habitats, R. tanezumi may also play a key role as a bridge host.

5. The recent discovery of new arenaviruses in rodents in Southeast Asia, with associated disease in humans in Cambodia, provides an opportunity to test this empirically. The three rodent species identified using our network approach are some of the potential maintenance hosts for these new emerging arenaviruses.

6. Synthesis and applications. Our results on rodents and their pathogens in Southeast Asia show that network analysis has a high potential to improve the surveillance of emerging zoonotic pathogens by targeting key host species and potential “emerging’ pathogen–rodent interactions in complex and heterogeneous landscapes.

1. 在复杂的生态系统中，识别可能在新发传染性人畜共患病（zoonotic diseases）出现过程中发挥关键作用的动物物种，仍是一项重大挑战。现有一类研究思路是利用宿主物种间现存的生态学与寄生虫学相似性信息，以预测未来病原体溢出（pathogen spillover）的最可能路径。
2. 本研究利用采集自泰国、柬埔寨与老挝不同生境的15种同域啮齿类（rodent）野外调查数据，基于啮齿类与人类之间共享的寄生虫（共17种蠕虫（helminth）和15种微寄生虫（microparasite））以及共享生境构建了关联网络。我们通过模块化性、亚群划分或节点中心性（node centrality）分析二部网络（bipartite networks）与单部网络（unipartite networks）的结构，以评估特定啮齿类物种的相对流行病学重要性。
3. 研究结果显示，在针对人畜共患病原（zoonotic agents）与共享生境构建的单部与二部网络中，黄胸鼠（Rattus tanezumi）、萨氏家鼠（Bandicota savilei）以及波利尼西亚鼠（R. exulans）始终被归入包含人类的亚群。这三种啮齿类在共享人畜共患病原的网络中均表现出较高的节点中心性，而其中两种在共享生境网络中中心性较高。尽管系统发育关系相近的啮齿类可能共享生境与寄生虫，但生境特化程度较低与更高的人畜共患寄生虫共享率存在关联。
4. 本研究结果凸显了这三种啮齿类的不成比例的重要性——它们与人类的连通性极高，这可能构成直接人畜共患病原体溢出的高风险。此外，黄胸鼠在生境网络中具有较高的中心性，因此可作为桥梁宿主（bridge host）发挥关键作用。
5. 近期在东南亚啮齿类中发现新型沙粒病毒（arenaviruses），且柬埔寨出现与之相关的人类病例，为我们开展实证检验提供了契机。通过本研究的网络分析方法鉴定出的三种啮齿类，正是这些新型新发沙粒病毒的潜在储存宿主（maintenance hosts）之一。
6. 总结与应用。本研究针对东南亚啮齿类及其病原体的分析结果表明，在复杂异质的景观中，网络分析通过靶向关键宿主物种与潜在的"新发"病原体-啮齿类互作关系，可有效提升对新发人畜共患病原体的监测能力。