Objective  Cities are the product of the evolution of human civilization. People share the fruits of the progress of civilization in cities, including the conveniences brought by culture, medical care, commerce, and technology. Since the reform and opening-up, Chinese urbanization has developed rapidly, leading the world in terms of scale and speed. New urbanization is one of the important connotations of Chinese-style modernization development. Spatial planning systems play a crucial role in modernization of national governance by providing support and guidance for the Chinese urbanization process. There are a number of ecological elements that affect the health of cities, including not only the green and blue spaces constructed by animals, plants and water bodies, but also a microbial world that is invisible to the naked eye. This research aims to provide new ideas for optimal design of urban microbes based on spatial planning and design under the “One Health” framework.

Methods/process  This research firstly elucidates the relationship between “One Health” and urban microbes, then explores the impact of urbanization on environmental microbes and the connection between environmental microbes and human health, and finally proposes ideas for optimizing the healthy urban microbial environment to realize the harmonious coexistence between human and nature.

Results/conclusion  Microbes, ubiquitous in nature, serve as the major link connecting humans with animals, plants and the environment. Microbes affect human health by affecting the microbial composition and diversity of the living environment and humans. Urbanization has a profound impact on microbial ecosystems, as changes induced by urbanization, including climate, land use and lifestyle changes, often reduce the diversity of environmental microbes and disrupt the balance of human microbes. As a result, it causes the development of allergic inflammation and other associated diseases in humans. Importantly, it is possible to improve human health by modulating the diversity of environmental microbes and manipulating the abundance of specific bacterial species. According to nature-based solutions, bringing nature back to cities and re-connecting urban residents with biodiverse environmental microbiomes are considered important potential measures to promote human health and reduce the prevalence of non-communicable diseases. As an important part of the urban ecosystem, urban green spaces can provide many ecosystem services closely related to human health, and can potentially play an important role in mitigating the negative impact of urbanization on environmental microbes and human health. Previous researches have shown that exposure to urban green space can increase the diversity of human skin and nasal microbiota and positively affect human health. Moreover, greenness and plant species are important factors affecting potential health risks in urban areas. Living in an increasingly interconnected microbial world, people urgently need a deep understanding of the composition, diversity and spatio-temporal distribution of urban and rural microbes. The spatial design of future healthy cities needs to fully take microbial elements into consideration. Spatial resource allocation is the core of healthy urban planning that focuses on reducing health risk exposure, improving the supply of health resources and promoting healthy lifestyles. Therefore, healthy urban planning should be carried out for the optimal design of microbial environment under the “One Health” framework, thus effectively bringing natural elements into the urban living environment, and building an urban ecosystem based on nature and health requirements. Future research should be strengthened in the following aspects: 1) Study the driving mechanisms of the composition, diversity and spatio-temporal distribution of urban microbes; 2) establish indicators or systems to evaluate the health of microbial communities in urban human settlements, and develop corresponding diagnostics technologies; 3) clarify how urban green space affects the composition and function of microbial community, so as to improve urban microbial diversity and function through urban green space optimization; 4) explore effective methods to regulate the composition of indoor environmental microbial community. The “One Health” concept and action plan strive to develop comprehensive strategies by fostering interdepartmental and interdisciplinary collaboration and recognizing the interconnectedness of humans, animals and the environment to address health challenges arising from urbanization, which will contribute to global health security and overall well-being. Conducting monitoring and research on the distribution, diversity and abundance of microbes in urban environments at various scales, and systematically analyzing the influence of all spatial elements on microbial populations, will furnish the scientific basis and technical support for promoting healthy urban planning under the “One Health” framework.