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Despite recent interest in land-use and land-cover (LULC) change effects on emerging infectious diseases (EIDs), the debate on global potential health threats remains polarizing. These depend on diverse LULC changes, different types of infectious disease systems, and spatio-temporal scales of studies. Here, using both a bibliometric and scoping review method, we summarize the reliability and availability of published relevant studies on LULC effects on mycobacteria, an important group of infectious bacteria that affect humans and both wild and domestic animals. We make connections of LULC with environmental changes (e.g. soils) that likely lead to an increased risk of mycobacteria spillover to human and other animal populations. An important feature of our review is a focus on research from the richest countries of the world, though some studies have been done in Africa, Asia and South America. Geographically, regions experiencing important LULC transformations, such as many tropical regions of Meso- and South America and Southeast Asia, have been given little or no attention in this important topic. Research onMycobacterium bovis,and to a larger extent onM. ulcerans,constitutes convincing illustrations of the importance of acknowledging shifts in spatio-temporal scales, from local to global and inter-annual to decadal ones, when evaluating responses of mycobacteria to LULC changes. However, studies on other pathogenic mycobacteria remain very much confined to local and dispersed scales. To date, the role of LULC change effects has not been adequately studied for many human and animal pathogens, and more research and attention to this issue is clearly needed. This review provides a comprehensive set of data on the updates of LULC change and their impact on animal and human mycobacterial infections. It also proposes several research recommendations, in particular to better understand the emergence of mycobacteria in context, by multiplying study sites in different regions of the world and in adopting an ecosystem-based perspective, in order to encourage interdisciplinary research better linking environmental microbiology, veterinary science and medical research. 

Pathogens such as bacteria, fungi and viruses are important components of soil and aquatic communities, where they can benefit from decaying and living organic matter, and may opportunistically infect human and animal hosts. One-third of human infectious diseases is constituted by sapronotic disease agents that are natural inhabitants of soil or aquatic ecosystems. They are capable of existing and reproducing in the environment outside of the host for extended periods of time. However, as ecological research on sapronosis is infrequent and epidemiological models are even rarer, very little information is currently available. Their importance is overlooked in medical and veterinary research, as well as the relationships between free environmental forms and those that are pathogenic. Here, using dynamical models in realistic aquatic metacommunity systems, we analyze sapronosis transmission, using the human pathogenMycobacterium ulceransthat is responsible for Buruli ulcer. We show that the persistence of bacilli in aquatic ecosystems is driven by a seasonal upstream supply, and that the attachment and development of cells to aquatic living forms is essential for such pathogen persistence and population dynamics. Our work constitutes the first set of metacommunity models of sapronotic disease transmission, and is highly flexible for adaptation to other types of sapronosis. The importance of sapronotic agents on animal and human disease burden needs better understanding and new models of sapronosis disease ecology to guide the management and prevention of this important group of pathogens.