Rethinking One Health: Microbial Foundations for Ecological Governance

ABSTRACT

The One Health (OH) framework has gained prominence in recent years, promoting an approach integrating the health of humans, animals, and the environment. However, its implementation as it pertains to the microbial world has largely prioritized zoonotic diseases, antimicrobial resistance, as well as pandemic preparedness and management, narrowing its ecological scope and confining microorganisms to the realm of pathogens. We explore the historical development of OH to identify key gaps and limitations and argue for the integration of microorganisms as ecologically constitutive, critical to sustain life processes and ecosystem functioning. We provide actionable recommendations, beginning with a shift in how microorganisms are conceptualized, extending to the development of microbial metrics and culminating in proposals for microbial governance to address current shortcomings and inform future policymaking. Collectively, these measures aim to strengthen the OH framework in confronting global challenges, including biodiversity loss and climate change, while aligning with its broader commitments to health and sustainable development.

One Health (OH) frameworks often approach health through bounded events and discrete risks. Ecological microbial foundations reposition microorganisms as constitutive elements of OH. Microbial metrics help trace ecological trajectories, disruptions, and recovery dynamics, providing process‐based indicators of ecosystem change. Microbial governance enables upstream, preventive, ecologically grounded approaches to health intervention and protection.

1. Introduction

While the environmental crises characterizing the first quarter of the 21^st century are intensifying, most notably through the transgression of six out of the nine planetary boundaries, including climate change, biosphere integrity, land‐system change, freshwater use, biogeochemical flows, and the proliferation of novel entities such as chemical pollution, their health implications are neither linear nor immediate [1, 2, 3]. Rather than acting directly, these large‐scale ecological disruptions reorganize the biophysical conditions, altering the relationships that underpin ecosystem functioning.

Microbial communities play essential roles in nutrient cycling, soil formation, organic matter turnover, water purification, and symbioses; disturbances to these microbial processes therefore propagate across food systems, ecosystem resilience, and disease ecology [4, 5, 6]. These cascading effects shape patterns of exposure, vulnerability, and disease risk in animals, plants, and humans, linking planetary‐scale environmental change to health outcomes across species and ecosystems [7, 8].

The recognition of these interdependencies has given rise to several integrative frameworks aimed at rendering the health‐environment nexus analytically tractable. Eco health and planetary health have been crucial in articulating the embeddedness of health within ecological and Earth system processes, largely advancing through academic, research, and advocacy networks [9, 10, 11]. One Health (OH), while conceptually overlapping with these approaches, has followed a distinct institutional trajectory [12]. Over the past two decades, OH has been formally adopted by major intergovernmental organizations—including the World Health Organization (WHO), the Food Agriculture Organization (FAO), the World Organization for Animal Health (WOAH, formerly OIE), and the United Nations Environment Program—and operationalized through surveillance systems, action plans, and regulatory instruments [13, 14].

This difference in institutional embedding has important consequences. Whereas Eco Health and Planetary Health have primarily functioned as critical and normative frameworks, OH has become a dominant governance paradigm for managing health risks at the human–animal–environment interface, particularly in relation to zoonoses, antimicrobial resistance (AMR), and biosecurity [11, 12, 15]. This institutional success, however, is inseparable from One Health's historical roots in comparative pathology and Schwabe's One Medicine [13], which centered on zoonotic disease transmission and clinical disease management [16]. While this orientation has proven effective in mitigating acute health threats, it has also perpetuated a framing of microorganisms primarily as pathogens to be monitored, controlled, or eradicated, a tendency that continues to shape contemporary OH practice [17].

Even as ecological dimensions have been incorporated into policy instruments such as the One Health Joint Plan of Action, microbial life largely enters governance through surveillance, risk anticipation, and AMR mitigation [14, 18]. In this configuration, microbes function as indicators or mediators of human and animal health outcomes rather than as ecological entities affected by environmental degradation in their own right [19, 20, 21]. This perspective is not unique to OH. Across integrative frameworks, microbial life is often subsumed under ecosystem services or risk management categories, with human health implicitly positioned as the primary endpoint of intervention [22]. Such an approach neglects the foundational ecological roles microorganisms play in sustaining ecosystem function and cross‐species health, despite growing recognition of environmental complexity [23, 24, 25], and risks promoting interventions that are narrowly targeted and ultimately unsustainable.

Efforts to address the ecological limitations of contemporary health governance are therefore likely to be most impactful if they engage directly with, and focus on the realignment of, OH, leveraging existing policy infrastructures, legal instruments, and funding mechanisms, while simultaneously interrogating and expanding the framework's underlying assumptions. Such realignment cannot be achieved simply by further broadening One Health's scope. Rather, we argue for a shift in perspective: one that thinks with microbes as configurators—active agents shaping ecological relations [26, 27]—rather than merely as risks to be managed or resources to be optimized. Such a reorientation is necessary if OH is to fulfil its integrative promise in the context of accelerating planetary change.

Building on this diagnosis, this conceptual paper draws on ecological and microbiological research [23, 24, 28, 29] to re‐examine key assumptions within OH and to propose governance‐oriented recommendations structured along three interconnected axes. First, we argue for a theoretical shift in how microorganisms are conceptualized, drawing on relational ontologies [30], to portray microorganisms as actors whose activities configure health and environmental systems. Second, this ontological shift enables the development of microbial metrics that extend beyond disease control, informing restoration efforts and public health policies. Third, these advances point toward a governance shift that integrates the protection of microorganisms into biodiversity conservation and global health strategies. By proposing a coordinated governance platform linking microbial science and policy making, this paper aims to address persistent gaps in the OH framework and to contribute to more responsible, durable, and ecologically grounded forms of microbial stewardship.

1. Glossary Box

Actor‐Network Theory (ANT)	A framework in science and technology studies that emphasises how both, human and non‐human actors (like microorganisms, tools, or environments) co‐create networks of relationships that shape outcomes [30].
Global change factors	Phenomena considered to be human‐caused factors of global environmental change [19].
Holobiont	The concept of an organism and its associated microbiome as a single ecological entity. We use it here to think of the boundaries between individual organisms and their environments. The holobiont reflects the co‐constitutive relationships between organisms and microbes and challenge the traditional notions of individuality in biology [31].
Instrumentalization	In this paper, the term refers to assigning value to entities, in this case microorganisms, mostly for their usefulness in achieving specific human goals, rather than for their roles within broader ecological systems [32].
Microbial Necromass	Dead microbial biomass contributing to soil carbon cycling and formation of stable organic matter [33].
Relational Ontology	A way of understanding organisms or entities as defined by their relationships and interactions with other components of a system [30, 34].
Symbiogenesis	Evolutionary theory proposing that new organisms or traits arise from long‐term symbiotic relationships [31].

2. Development of the One Health Framework From Medicine

Rudolf Virchow is often regarded as a foundational figure in the development of the OH concept, having established connections between human and animal diseases through comparative pathology as early as 1855 [16]. His work played a central role in shaping modern health sciences, and continues to influence OH thinking today. Building on Virchow's legacy, Calvin Schwabe, an American veterinarian, introduced the One Medicine concept in 1984 [37], advocating for the integration of human and veterinary medicine to address zoonotic diseases. Over time, One Medicine evolved into the OH framework, formally adopted by the WHO‐FAO‐OIE tripartite in the early 2000s [13] (Figure 1)

FIGURE 1.

Timeline of the One Health conceptual development, synthesized from key sources on One Health and different institutional developments [13, 16, 17, 23, 35, 36].

This trajectory was further reinforced through conferences organized by the Society of Tropical Veterinary Medicine and the Wildlife Disease Association [38] which focused on disease control and emerging infections across domestic and wild animal populations. The One World, One Health conference, organized by the Wildlife Conservation Society, led to the formulation of the 12 Manhattan Principles [35]. While influential, these principles exhibited a predominantly anthropocentric bias, emphasizing “combating threats to the health of life on Earth, the impacts these have on people, food security and their economies.” [38] This emphasis continued in subsequent initiatives, including the First International One Health conference in Melbourne, Australia, in 2011, which focused primarily on zoonotic disease exposures and its consequences [39].

Indeed, OH has meaningfully contributed to the management of zoonotic diseases and the coordination of public and global health responses. These efforts have been instrumental in building systems for early detection, surveillance, and international collaborations, exemplified by initiatives such as the Pan‐African Rinderpest Campaign or the Global Fund to Fight AIDS, Tuberculosis, and Malaria [13].

Their scope expanded to include ecological and environmental dimensions with the Berlin Principles in 2019 [18, 40]. However, this disease‐centered orientation has shaped how microbial life enters One Health governance. Even when environmental dimensions are acknowledged, microbes are rendered visible primarily through surveillance, risk anticipation, and resistance mitigation, limiting interconnectedness to transmission, and overlooking ecological feedback loops and broader conditions of instability, which remain largely overlooked [5, 41, 42, 43].

More recent efforts to expand OH through explicit engagement with microbial interconnectedness, most notably the 2025 Lancet One Health Commission and the One Health World Microbiome Partnership Summit, illustrate both progress and the persistence of these limitations. Although socio‐environmental dimensions are introduced, they enter alongside economic concerns as coequal domains to be balanced, rather than recognizing ecological systems as a precondition for all activity. While these initiatives move beyond a strictly pathogen‐centered view by foregrounding microbiomes, they nonetheless narrow the scope of microbial consideration to “host‐associated,” bounded, technologically tractable communities. Across proposed applications from personalized medicine and sustainable agriculture to ecosystem restoration and climate mitigation microbes are predominantly framed as resources to be monitored or engineered [36, 44, 45]. Such framings reinforce a logic where microbial life matters insofar as it affects human‐defined outcomes. Furthermore, by conflating microbial life with “host‐associated” microbiomes, these approaches sideline vast domains of free‐living and ecologically consequential microbes and leave the anthropocentric assumptions underpinning microbial governance largely unexamined [46, 47].

3. The Microbial Blind Spot

The historical disease focus of OH created a systematic gap around the non‐pathogenic roles of microbes, while more recent developments still narrow microbial life to bounded and instrumental forms, leaving its full ecological breadth unaddressed. To clarify what remains at stake, we briefly recall some microbial roles already well established in ecological research. bacteria, fungi, archaea, protists, and viruses, together with the communities they form and their symbiotic relations with macroorganisms—the “holobiont” (understood as the organism and its microbiome), proposed as a way to rethink boundaries between organisms and their environments [31] continuously mediate and transform processes across every biological scale [48, 49]. Their roles in biogeochemical cycles and other environmental functions are well established in ecological research [23, 50]. In fact, the overwhelming majority of microbes do not cause disease in humans, animals, or plants, with pathogenic species accounting for less than 1% of known microbial diversity [5, 51, 52, 53].

Microbes play an essential role in nutrient cycling, decomposing organic matter in the soil and releasing nutrients [28]. For instance, Trichoderma harzianum increases soil organic matter decomposition and nutrient availability that can be taken up by plants and other soil microbes [54, 55]. Other taxa fix essential nutrients from the atmosphere, such as nitrogen, and mobilize other nutrients, such as phosphorus and potassium [25, 56]. Furthermore, as microbes die, they generate necromass that is important for soil carbon storage, and microbes thus form an integral part of the carbon cycle [57, 58].

In addition, microorganisms sustain symbiotic relations across plants [59], and animals, including humans [60]. For example, Pseudomonas fluorescens protects crop roots by producing 2,4‐Diacetylphloroglucinol, an antiviral, antibacterial, and antibiotic phenol [61, 62]. Similarly, arbuscular mycorrhizal fungi protect plants from fungal‐ or nematode‐caused disease, while strengthening plants’ resilience and shaping broader soil‐plant interactions [63, 64]. In humans, symbiont strains such as Clostridium butyricum are correlated with the modulation of immune responses, facilitating nutrient absorption and strengthening the gut barrier [65, 66]. Even viruses, often considered solely as pathogens, are necessary within biogeochemical cycles [67], and in evolution. For example, endogenous retroviruses have contributed to the evolution and formation of the mammalian placenta [68]. Similarly, phages—viruses of bacteria in particular, contribute significantly to organic matter cycling by the process of lysis in microbial populations, where they release organic compounds and nutrients back into the environment, supporting production and availability of nutrients within ecosystems [69]. Their great number—estimated to be 10³⁰ in the oceans alone makes them the most abundant genetic entities on Earth [69]. Yet, their ecological roles are often overlooked in discussions of ecosystem health, and research efforts are directed towards their use as “tools” against bacterial threats [70].

These roles demonstrate the centrality of microorganisms by indicating how they can reveal ecological disruption before deterioration becomes obvious at other levels of a system. Microorganisms can serve as sensitive indicators of soil functioning [71], water quality [72], and broader efforts to secure safe and nutritious food systems [73, 74]. The integrity of microbial communities can likewise provide insights into ecological disruptions driven by global change factors, including climate change, related transformations of food systems and environmental microbiomes [29, 75, 76].

When such dynamics are addressed primarily through technological innovation and risk surveillance, the environmental conditions producing them often remain unchanged. Human activities continually restructure microbial ecologies in ways that favor pathogenicity [77, 78], displace microorganisms into new ecological niches, and intensify selective pressures associated with AMR [21, 77, 79, 80].

Current efforts to broaden OH through ecological, social, and health integration represent an important advance. Yet, these efforts remain incomplete so long as microorganisms are treated as objects of surveillance or intervention rather than as constitutive components of ecosystem functioning. Recognizing microorganisms in this broader sense shifts attention from downstream crisis management toward the environmental conditions that sustain long‐term stability, resilience, and cross‐species health. Such orientation aligns with recent recommendations from the Scientific Advice Mechanism to the European Commission [81] advocating greater collaboration across environmental and health challenges [17, 36, 81].

4. Relational Framework for Microbial Integration: Metrics and Governance

Addressing this persistent gap requires a prior shift in how microorganisms are understood. Once microbial life is treated as ecologically constitutive, the consequences extend to the metrics through which they are assessed and the forms of governance built upon those assessments. We therefore develop a tripartite framework, (i) an ontological reconceptualization of microorganisms, (ii) the turn to metrics attuned to microbial functionality and ecosystem stability, and (iii) thinking of governance structures capable of protecting microbial complexity as a public good [45]. Altogether, these foster approaches and measurements practices centered on ecological commitments as intrinsic priorities, as echoed in the Berlin Principles [18].

4.1. Relational Ontologies

Central to this reframing is the recognition that microorganisms are not merely isolated agents of disease or instrumentalized resources for human benefit. Rather, it requires rethinking the terms through which microbial life becomes visible, acknowledging both microbial agency and the constitutive ecological roles microorganisms play within ecosystems [22, 82]. Microorganisms enact what can be described as relational agency, meaning they shape and are shaped by the ecological systems they inhabit (see Figure 2). Their roles, therefore, emerge through the dynamic relationships they form with other species, rather than being determined by fixed traits [30, 83]. We build this reframing from a set of philosophical and ecological perspectives, examples of which include Actor‐Network Theory [30], symbiogenesis [31], the Gaia Hypothesis [84], and the evosystem [85], which collectively challenge reductionist models of life. These perspectives, while non‐exhaustive, help us situate microorganisms as relational agents. In the context of OH, this ontological turn supports the idea of acknowledging interconnectedness, and changes what must be protected and measured: not only pathogens, diversity counts, or isolated functions, but the conditions that sustain microbial relations, functionality, and long‐term ecological trajectories [86].

FIGURE 2.

Drawing on conventional One Health schematics, this figure positions microorganisms in the center of the One Health framework [14] as an encompassing sphere including humans, animals, and plants through both symbiotic relationships and free‐living microbial life, through all environments confounded. This framing does not suggest that microorganisms are more important than other forms of life; instead, microbes are embedded within and frequently mediate the interactions generating ecological networks. For instance, through holobiont relationships, microorganisms span across multiple species, and connect biological systems across scales [31]. This perspective supports a shift in OH moving toward a more ecological and relational understanding of health, emphasizing interdependence over isolated outcomes.

This shift carries direct implications for regulations and interventions. Environmental degradation cannot be addressed solely at the level of macro‐effects or of short‐term outcomes. Pollution, industrial agriculture, land‐use, and restoration must be assessed in terms of how they restructure microbial conditions, since those conditions are constitutive of ecosystem functioning and, ultimately, of plant, animal, and human health [5, 19, 71]. This also implies moving beyond definitions of health tied to productivity, or optimizable endpoints. A system may remain productive while being ecologically destabilized; yield is neither a sufficient nor a necessary indicator of fertility, and still less of health. Policy should aim less at optimizing fixed states and more at sustaining the conditions under which living systems can persist, recover, and reorganize.

The same shift extends to measurements. Microbial data may be incorporated beyond an additive layer of indicators that leave such static interpretive logics intact. Instead, they should be read through spatio‐temporal assessments, responsive to land‐use changes, pollution, climate pressures, and interacting disturbances [19, 76, 87]. This favors process‐based indicators able to detect instability, delayed recovery, hysteresis, or functional divergence over time. In this sense, a relational ontology supports a transition of governance from reactive to proactive, by changing the logic of intervention. Proactive governance does not simply wait for a pathogen outbreak through constant monitoring; rather, it seeks to identify and actively reduce the underlying conditions that make such outcomes more prone to emerge.

What follows with this shift is then a reorientation of OH towards process‐based evidence, upstream regulation, and prevention grounded in the conditions of ecological life instead of the simple management of its failures after collapse becomes visible.

4.2. Microbial Metrics for One Health

Microbial health metrics are beginning to enter environmental policy frameworks. The latest European Union State of the Soil Report [88] recognizes microbial diversity as an important component of soil health, a significant institutional step. However, diversity alone is insufficient to assess ecosystem function. Greater microbial diversity, for example has been associated with a lower number and abundance of resistance genes in the soil, but not in water [89], showing its significance is context‐dependent and cannot be generalized. We want to use this opportunity to expand the use of microbial data.

Several existing tools already provide informative microbial signals, including wastewater surveillance of AMR [90], microbial biomass and enzyme activity assays [50], and functional gene quantification [91]. The task now is to mobilize them differently, not only as snapshots, but as registers of instability, recovery trajectories, and functional dynamics over time.

In soils, this means linking microbial indicators to land‐use histories and restoration efforts. In rewetted peatlands, for instance, methane sink or source behavior should be interpreted through the temporal relation between hydrology, greenhouse gas fluxes, and microbial functional groups. A site that appears restored at the vegetation level may display different microbial trajectories, with direct consequences for methane production and carbon storage, such as shown by mismatches between aboveground restoration and microorganisms [87, 92, 93].

In agricultural soils, nitrogen‐fixing bacteria and phosphorus‐solubilizing fungi [63, 94] are often used as correlates of fertility or yield [95], overlooking the broader ecological disruptions wrought by production‐driven agricultural logics. Considered more broadly, such microbial indicators can reveal how fertilizer regimes, pesticides, and irrigation practices progressively restructure microbial conditions over time. In this sense, microbial metrics can help trace nutrient turnover, and clarify the microbial dimensions to carbon storage and to the resilience of food‐systems [33, 96, 97].

Antimicrobial resistance (AMR) provides an especially instructive case. Rather than treating it solely as a discrete threat, AMR monitoring can also be understood as reflecting deeper ecological disruptions, thereby functioning as a diagnostic tool revealing the environmental conditions that give rise to risk [41, 42, 43, 78]. Intensified ecosystem stressors, including antibiotics, heavy metals, and pesticides, create conditions favoring the amplification and dissemination of resistance genes [80, 98, 99, 100, 101]. Mechanisms such as efflux pumps can emerge in response to multiple chemical exposures, contributing simultaneously to pesticide and antibiotic resistance [102, 103]. Resistance profiles associated with particular contaminants can therefore help identify where chemical remediation, reduced inputs, or stricter regulatory interventions are needed (see Table 1).

TABLE 1.

Current one health action point no. 5 versus ecological foundation proposal.

Current model: Action 5, Curbing the Silent Pandemic of AMR.	Our proposal: AMR: Microbial Adaptation to Environmental Stress.
Surveillance of “hot‐spots”, regulation of antibiotic use in humans and livestock, awareness campaigns [14, 16].	Recognition of AMR as an adaptive response to environmental stressors [77, 98, 107].
AMR is seen mostly as a behavioural problem (e.g., antibiotic misuse), combined with other factors such as poor hygiene or governance failure (in certain regions) [13].	AMR serves as an indicator of ecosystem pressure from industrial agriculture, pollution and habitat degradation [5, 21, 23, 108].
Solutions: better hygiene, strict medical control, alternative therapies [14, 16].	Solutions: restructuring of supply systems (e.g., food chain), regulation of industrial emissions and chemical inputs (e.g., antibiotics, heavy metals, plastics), and ecosystem restoration [78].
Goal: control, mitigation, sometimes microbial eradication.	Goal: microbial stability can help restore conditions limiting AMR selective pressures [21, 22].

In urban settings, microbial indicators can similarly be integrated into environmental monitoring as signals of ecological disturbance and exposure inequality [104, 105]. Shifts in microbial communities can help reveal how pollution, land‐sealing, waste flows, and built‐environment conditions reorganize ecological exposures across neighborhoods. Considered together, wastewater and urban soil metrics can inform immediate public health protection as well as infrastructure planning, pollution control, and environmental justice strategies [90, 106].

As given in Table 1 Action Point No. 5 of the current One Health Joint Program 2022–2026, titled Curbing the Silent Pandemic of AMR [14]. Our ecological reframing of microorganisms within the OH model suggests a broader approach capable of addressing some of the underlying ecological drivers of global health challenges more effectively. We also propose an alternative approach that better reflects the ecological dimensions of AMR and more fully integrates microbes into the framework. Such an ontological shift could lead to a reconsideration of each existing Action Point through a more explicitly ecological and microbial lens.

Framed within a OH perspective, these approaches extend beyond monitoring; they register ecological trajectories, diagnose environmental pressures, as well as support and enable earlier interventions. In doing so, they reveal how human activities maintain, degrade, or redirect the conditions which ultimately sustain microbial functionality [97]. Despite the promises ahead, microbial metrics face challenges, such as context‐dependent specificity of microbial environments, complexity of lateral gene transfer [109, 110], or interpretation challenges. These potential limitations should not be invoked to delay action. Used carefully, these metrics can support ecological well‐being and ecosystem resilience across soils, food systems, and public health.

4.3. Microbial Governance

Many existing institutions support microbiology research and conservation, from scientific societies to culture collections. However, there is a missed opportunity which can bridge microbial research concerns and policy‐making [82]. Unlike wildlife or forests, microorganisms have no voice at the level of international governance, despite their central roles in biodiversity, public health and climate resilience. We propose the creation of an international platform for microbial governance, whose tasks would include defining the context‐specific microbial indicators, establishing shared interpretative standards and integrating these into existing biodiversity, wastewater, and restoration frameworks. This international platform would bring together, among others, representatives from microbial biobanks, such as the American Type Culture Collection and the Leibniz Institute DSMZ in Germany; policy experts; and conservation organizations such as the International Union for the Conservation of Nature, which recently convened a meeting on microbial conservation, that resulted in the creation of the Microbial Conservation Specialist Group [111, 112, 113, 114]. It could also foster collaborations with related institutions, including the Intergovernmental Platform on Biodiversity and Ecosystem Services and the European Environment Agency [115, 116].

This new platform would operate as a formal working body, attached to existing initiatives within the OH framework, thereby avoiding the creation of parallel bureaucratic structures while facilitating the integration of microbial data into health and ecosystem restoration strategies. Its mandate would include the development of microbial indicators and standardized protocols such as soil restoration, wastewater AMR surveillance, and pollution monitoring. In doing so, it would establish reference baselines and interpretive guidance, and harmonized reporting formats across institutions. Scientific bodies would be responsible for developing and validating these indicators, reference systems, and long‐term assessments; intergovernmental organizations could incorporate them into reporting frameworks; and national or regional authorities could integrate them into environmental assessments, ensuring that restoration benchmarks, public funding, and enforcement strategies are informed by and implemented with microbial considerations in mind. Such an approach would help move microbial governance from the realm of scientific recommendations toward concrete regulatory obligations, particularly in domains currently fragmented across environmental and health agencies.

Microbial governance would not replace immediate risk management, but rather provide a coordinated, cross‐sectoral foundation for prevention. From a policy perspective, this represents the logical next step for institutions aiming to operationalize the holistic ambitions of OH, the Sustainable Development Goals, and related global frameworks. Perhaps most importantly, it requires recognizing that microbial life matters even when it is not performing an immediately visible function. Microorganisms shape ecological relationships, signal environmental change and contribute to the integrity and stability of ecosystems. Recognizing microbial life in this way requires policy frameworks to treat microbes as integral components of the very processes such frameworks aim to protect.

5. Limitations

While we seek to reframe microorganisms within the OH model through a more comprehensive integration of their essential environmental contributions, it is equally important to acknowledge the profound limits of our understanding of their ecological functions. Microorganisms are not a panacea for humanity's missteps. Researchers and stakeholders must act responsibly and ensure innovation does not misrepresent or misuse microbial life as tools for human convenience [117]. Such caution is necessary as decisions on land‐use, agriculture, and biodiversity are shaped by a complex interplay of scientific knowledge, cultural traditions, political systems and economic pressures [118]. In such contexts, microbial interventions risk being redirected toward short‐term optimization, rather than supporting long‐term ecological functioning.

6. Conclusion

One Health has become an influential framework for linking health across human, animal, and environmental domains, with recent expansions extending its attention to microbial life. However, microorganisms continue to enter this framework primarily through its longstanding focus on disease. While this broadening appears to incorporate microbes, it often does so in ways that remain centered on associations with larger organisms or instrumental roles, leaving their broader ecological constitutiveness unaddressed. We have argued that such limitations matter since microorganisms actively shape and participate in the conditions in which ecosystem functioning and cross‐species health unfold.

Recognizing microorganisms as ecologically constitutive agents does not diminish the importance of pathogens or biomedical intervention. Rather, it situates these within broader conditions that ultimately shape the emergence, persistence, and distribution of health risks across species and environments. Such an expanded ecological scope transforms what becomes measurable, how interventions are designed, and redirects attention towards process‐sensitive metrics capable of registering dynamics such as disturbance, recovery, and functionality over time. At the level of governance, it calls for arrangements that can act on the upstream conditions influencing microbial dynamics, rather than focusing solely on downstream outcomes. From such an ontological perspective, integrating microorganisms is a necessary condition for moving the OH framework toward a more relational, preventive, and ecologically grounded approach to health, one that renders its claims of interconnectedness materially meaningful.

Author Contributions

Andrea Fernandez Diaz and Louis‐Patrick Haraoui conceptualized the paper. Andrea Fernandez Diaz wrote the original draft. Andrea Fernandez Diaz, Frédéric Keck, Melissa Melby, Vinh‐Kim Nguyen, and Louis‐Patrick Haraoui contributed to reviewing and editing the manuscript.

Conflicts of Interest

The authors declare no conflicts of interests.

Conflicts of Interest

The authors declare no conflicts of interest.

Data Availability Statement

Data sharing not applicable to this article as no datasets were generated or analysed during the current study.