School of Natural Sciences, University of Tasmania, Australia.
Antarctic Climate & Ecosystems Cooperative Research Centre, University of Tasmania, Australia; Institute for Marine and Antarctic Studies, University of Tasmania, Australia.
Sci Total Environ. 2020 Oct 10;738:140337. doi: 10.1016/j.scitotenv.2020.140337. Epub 2020 Jun 22.
Over half of people live in cities and while urban environments offer myriad social, cultural and economic benefits, they alter the microbial communities to which people are exposed: with potentially important but underexplored health impacts. In particular, higher rates of asthma and allergies in urban areas have been linked to urban-altered microbial communities - including aerial microbial communities. To date, however, there has been no synthesis of the disparate literature on the impacts of urbanisation on aerial microbial communities, making it difficult to ascertain potential health impacts. We fill this knowledge gap by systematically examining studies that compare the characteristics (e.g. microbial abundance/diversity) and/or health effects of airborne fungal and bacterial communities (hereafter referred to as 'aerobiomes') across urban and rural locations. We included 19 studies, with 31 distinct urban-rural comparisons, in our analysis. We found that rural aerobiomes more often have a greater abundance of microbes (57% of studies). Aerobiome diversity was under-reported but when comparisons were made, rural aerobiome diversity was often higher (67%). Only two studies experimentally examined the impact of urban and rural aerobiomes on human health outcomes; both found rural aerobiomes shifted immune function away from allergic (Th2-type) responses. Overall, we conclude that significant gaps remain in our understanding of how urbanisation impacts aerobiomes and the health implications of those changes. We highlight the need to standardise methods and make aerobiome data open access to facilitate cross-study comparisons. Further mechanistic studies are urgently needed to examine the impact of aerobiome composition on immune function to demonstrate how urban-driven changes to the aerobiome impact human health - ultimately facilitating the development of healthier cities.
超过一半的人生活在城市中，虽然城市环境提供了无数的社会、文化和经济效益，但它们改变了人们所接触的微生物群落：这可能会产生重要但尚未得到充分探索的健康影响。特别是，城市地区哮喘和过敏的发病率较高与城市改变的微生物群落有关，包括空气微生物群落。然而，迄今为止，还没有对城市化对空气微生物群落的影响的不同文献进行综合，因此难以确定潜在的健康影响。我们通过系统地检查比较城市和农村地区空气真菌和细菌群落（以下简称“空气微生物组”）特征（例如微生物丰度/多样性）和/或健康影响的研究，填补了这一知识空白。我们的分析包括 19 项研究，其中有 31 个不同的城乡比较。我们发现，农村空气微生物组中微生物的丰度往往更高（57%的研究）。空气微生物组多样性的报道较少，但当进行比较时，农村空气微生物组的多样性往往更高（67%）。只有两项研究实验性地研究了城市和农村空气微生物组对人类健康结果的影响；两项研究都发现农村空气微生物组改变了免疫功能，使其远离过敏（Th2 型）反应。总的来说，我们得出的结论是，我们对城市化如何影响空气微生物组以及这些变化的健康影响的理解仍然存在重大差距。我们强调需要标准化方法并开放空气微生物组数据，以促进跨研究比较。迫切需要进一步进行机制研究，以研究空气微生物组组成对免疫功能的影响，从而证明城市驱动的空气微生物组变化如何影响人类健康，最终促进更健康的城市的发展。
