Burthe Sarah J, Schäfer Stefanie M, Asaaga Festus A, Balakrishnan Natrajan, Chanda Mohammed Mudasssar, Darshan Narayanaswamy, Hoti Subhash L, Kiran Shivani K, Seshadri Tanya, Srinivas Prashanth N, Vanak Abi T, Purse Bethan V
UK Centre for Ecology & Hydrology, Edinburgh, United Kingdom.
UK Centre for Ecology & Hydrology, Wallingford, United Kingdom.
PLoS Negl Trop Dis. 2021 Apr 1;15(4):e0009243. doi: 10.1371/journal.pntd.0009243. eCollection 2021 Apr.
Zoonoses disproportionately affect tropical communities and are associated with human modification and use of ecosystems. Effective management is hampered by poor ecological understanding of disease transmission and often focuses on human vaccination or treatment. Better ecological understanding of multi-vector and multi-host transmission, social and environmental factors altering human exposure, might enable a broader suite of management options. Options may include "ecological interventions" that target vectors or hosts and require good knowledge of underlying transmission processes, which may be more effective, economical, and long lasting than conventional approaches. New frameworks identify the hierarchical series of barriers that a pathogen needs to overcome before human spillover occurs and demonstrate how ecological interventions may strengthen these barriers and complement human-focused disease control. We extend these frameworks for vector-borne zoonoses, focusing on Kyasanur Forest Disease Virus (KFDV), a tick-borne, neglected zoonosis affecting poor forest communities in India, involving complex communities of tick and host species. We identify the hierarchical barriers to pathogen transmission targeted by existing management. We show that existing interventions mainly focus on human barriers (via personal protection and vaccination) or at barriers relating to Kyasanur Forest Disease (KFD) vectors (tick control on cattle and at the sites of host (monkey) deaths). We review the validity of existing management guidance for KFD through literature review and interviews with disease managers. Efficacy of interventions was difficult to quantify due to poor empirical understanding of KFDV-vector-host ecology, particularly the role of cattle and monkeys in the disease transmission cycle. Cattle are hypothesised to amplify tick populations. Monkeys may act as sentinels of human infection or are hypothesised to act as amplifying hosts for KFDV, but the spatial scale of risk arising from ticks infected via monkeys versus small mammal reservoirs is unclear. We identified 19 urgent research priorities for refinement of current management strategies or development of ecological interventions targeting vectors and host barriers to prevent disease spillover in the future.
人畜共患病对热带社区的影响尤为严重，且与人类对生态系统的改变和利用有关。对疾病传播的生态理解不足阻碍了有效管理，管理往往侧重于人类疫苗接种或治疗。更好地从生态角度理解多媒介和多宿主传播、改变人类接触的社会和环境因素，可能会带来更多样化的管理选择。这些选择可能包括针对媒介或宿主的“生态干预措施”，这需要对潜在的传播过程有充分了解，这些措施可能比传统方法更有效、更经济且更持久。新的框架确定了病原体在发生人类溢出之前需要克服的一系列层次障碍，并展示了生态干预措施如何加强这些障碍并补充以人类为中心的疾病控制。我们将这些框架扩展到媒介传播的人畜共患病，重点关注基孔肯雅森林病病毒（KFDV），这是一种由蜱传播的、被忽视的人畜共患病，影响印度贫困森林社区，涉及蜱和宿主物种的复杂群落。我们确定了现有管理针对的病原体传播的层次障碍。我们表明，现有干预措施主要侧重于人类障碍（通过个人防护和疫苗接种）或与基孔肯雅森林病（KFD）媒介相关的障碍（对牛和宿主（猴子）死亡地点的蜱进行控制）。我们通过文献综述和与疾病管理人员的访谈，审视了现有KFD管理指南的有效性。由于对KFDV - 媒介 - 宿主生态学，特别是牛和猴子在疾病传播周期中的作用缺乏实证理解，干预措施的效果难以量化。据推测，牛会使蜱虫数量增加。猴子可能是人类感染的哨兵，或者据推测是KFDV的扩增宿主，但通过猴子感染的蜱虫与小型哺乳动物宿主产生的风险空间尺度尚不清楚。我们确定了19项紧迫的研究重点，以完善当前的管理策略或制定针对媒介和宿主障碍的生态干预措施，以防止未来疾病溢出。
