Doctoral Dissertation Research - Humans as reservoirs: Historical microbiomes uncover hidden zoonotic pathways

人口迁移到世界上几乎每一个环境，作为这一过程的一部分，改变了当地的生态并与之融合。人类对环境的改变，如砍伐森林，极大地促进了人畜共患病的传播，包括病原体（细菌、病毒和其他微生物）从动物传播到人类，以及从人类传播到动物。人类改变的环境对海洋哺乳动物种群的影响研究较少。这个博士论文研究项目调查人类病原体到海洋哺乳动物种群的传播，使用保存在历史上的海洋哺乳动物遗骸上的微生物作为测量人类-动物病原体传播的独特资源，并探索人类改变对海洋环境的影响。该项目及其成果的传播有助于通过出版物和与国家公园管理局的外联活动，科学家Skype和俄克拉荷马州路易斯斯托克斯少数民族参与联盟的STEM指导，在人类学家，保护生物学家和环境生态学家之间建立合作研究。沿海径流增加了人类病原体和抗生素进入环境的机会。这可能导致动物传染病在野生动物中的传播和抗生素耐药性的环境选择。重要的是，肺炎克雷伯氏菌，一种常见的医院获得性人类感染，已成为加州海峡群岛沿岸加州海狮的地方病。此外，在环太平洋地区沿着还记录了肺炎克雷伯氏菌（hvKp）的高毒力菌株。然而，这一传播事件的起源尚不清楚。本项目研究利用博物馆藏品将肺炎克雷伯氏菌引入加州海狮种群。博物馆的藏品可以为研究环境变化和病原体的出现提供一个时间轴。研究人员使用宏基因组测序对加州海狮牙结石重建微生物群落，并将微生物多样性的变化与人类活动联系起来。研究人员还对肺炎克雷伯菌标本进行溶液中DNA捕获，以确定存在哪些菌株。通过调查加州海狮的口腔微生物组，研究人员评估是否有任何人为改变的微生物组允许更容易地传播肺炎克雷伯氏菌到海狮种群。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Human populations have migrated to nearly every environment in the world, and as part of this process have modified and integrated with local ecologies. Human alterations to the environment, such as deforestation, contribute significantly to zoonotic disease transmission, including transmission of pathogens (bacteria, viruses, and other microorganisms) from animals to humans, and from humans to animals. Less well studied are the impacts of the human-altered environment on marine mammal populations. This doctoral dissertation research project investigates the transmission of a human pathogen into marine mammal populations, uses preserved microorganisms on historical marine mammal remains as a unique resource to measure human-animal pathogen transmission, and explores the impact of human alterations on the marine environment. This project and the dissemination of its results serve to build collaborative research among anthropologists, conservation biologists and environmental ecologists through publication and through outreach with the National Parks Service, Skype a Scientist, and STEM mentorship for the Oklahoma Louis Stokes Alliance for Minority Participation. Coastal runoff increases the introduction of human pathogens and antibiotics into the environment. This can lead to the spread of zoonotic disease in wildlife and the environmental selection for antibiotic resistance. Of importance, Klebsiella pneumoniae, a common hospital acquired infection of humans, has become endemic among California sea lions along the California Channel Islands. In addition, a hypervirulent strain of Klebsiella pneumoniae (hvKp), has been documented along the Pacific Rim. However, the origin of this transmission event is unknown. This project studies the introduction of Klebsiella pneumoniae into the California sea lion population using museum collections. Museum collections can provide a timeline for studying environmental alterations as well as pathogen emergence. The investigators use metagenomic sequencing on California sea lion dental calculus to reconstruct the microbial community and link changes in microbial diversity to human activity. The investigators also perform in-solution DNA capture on specimens with Klebsiella pneumoniae to determine which strains are present. By investigating the oral microbiomes of California sea lions across time, the investigators assess whether any human-mediated alteration to the microbiome allowed for easier transmission of Klebsiella pneumoniae into the sea lion population.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.