Are perspectives on diseases without a human agent (empirical perspective) possible? “ From the disease image perspective (o1) through the cooperative discourse (02-03), and the “war frame” (04), Hector Rodriguez advances a point of view that conceives of a person as part and support of an ecological community. And what if “the bacteria that inhabit a person’s body are to a large extent unique to that person”? The assumptions of a microbial ecosystem define what it means to be person, so that a person is an ecological community. How ought we to think of personal identity when we consider the role of built spaces and dynamic interactions in shaping our microbial signatures?
**feature image: Transmission electron microscopic image of an isolate from the first U.S. case of COVID-19. Note the blue spherical particles are viral-colonised. (CDC: Centers for Disease Control and Prevention). Found on The Harvard Gazette for an article highlighting, “New study shows differences between patients who survived severe COVID-19 and patients who died from it.” Read 20 August 2022: https://news.harvard.edu/gazette/story/2020/11/antibody-evolution-may-predict-covid-19-outcomes/
To read the entire “Framing Diseases” series by Hector Rodriguez [… …]
The methods I have thus far discussed depend, at least in part, on the first-person articulation of first-person experience. The person who suffers the illness constructs an account of her experience. It is her own account of her own experience. But there are ways of thinking of disease that do not involve a human agent giving an account of herself. Other frames can be constructed wherein the person is conceived not as a point of view in search of articulation but as the support of an ecological community. What would this kind of frame be like?
I noted earlier the possibility of using the language of balance and imbalance, drawn from systems science, to describe health and disease. The notion of an equilibrium state also suggests a way of understanding what it is to be a person, beyond the notion of health and disease, in terms of one’s “microbial milieu”, and to think of any individual’s microbiome as an ecosystem, since the concept of an ecosystem encompasses the idea of striving towards a state of equilibrium.  Jack Gilbert has recently proposed that the biogeography of the microorganisms dwelling in a human being’s gut has certain features of “island biogeography” (or “insular biogeography), i.e. of the community of species dwelling in isolated islands. In particular, Gilbert stresses “the dispersal, local diversification, environmental selection, and ecological drift of biological life interacting with a new environment.”  We can then think of a person’s microbial ecosystem, then, as an island community.
In elaborating this perspective, Gilbert refers to research by Ana Zhu, Shinichi Suangawa, Daniel Mende, and Peer Bork, who have stressed the differences between the gut bacterial species across individuals.  The bacteria that inhabit a person’s body are to a large extent unique to that person. One of several reasons for this uniqueness that Gilbert has noted is that the bacteria in a child’s gut are from early on specific to that child’s mother: “from her vaginal tract, from skin and oral contact, or through breast milk.” The microbes that dwell inside one’s body are “associated with the mode of delivery: either through the vagina or through the skin” in case of Caesarean section.  Other sources involve the objects that children often handle or put into their mouths, etc. Although our microbial signature eventually stabilizes as the child matures, environmental factors continue to influence its development.
Reflection on our own microbial ecosystem can lead to a reconfiguration of our sense of what it means to be a person. We can then think of a person’s changing microbiome, for instance, as a system of historical landmarks that preserve a record or trace of the person’s biography from the early moments of life. From this standpoint, it is possible to recognise this microbial community as intrinsic to the person’s own identity, as marking who it is that the person essentially is.
Moreover, the gut microbiome is a dynamic community that goes through a process of structural change (ecological succession), leading to a further diversification of each person’s microbial island community. The uniqueness and diversification of a person’s microbial community also depends on its members’ interactions with mechanisms developed by the human body to work with and sustain functionally advantageous microorganisms. This uniqueness and diversity may help to explain the nature of each human being’s response, positive or adverse, to different kinds of treatment. Gilbert stresses that greater knowledge of different people’s island communities may lead to the development of treatment methods and resources attuned to different individual persons. He refers to participatory citizen science projects, such as American Gut, where individuals collect samples of their own microbiomes for analysis.
I want to stress here the possibility of drawing on our knowledge of the uniqueness and diversity of our own microbiomes for an experimental philosophical project capable of reconfiguring our concept of humanness. This project might experiment with different ways of thinking of persons: we might for instance explore what it means to think of ourselves not as individuals but as communities undergoing ecological succession. We can think of the person as a communal superorganism. The value of the person might then reside not only in the specificity of her mental life and conscious choices, but also in the community which she sustains, or perhaps the community which she is. The old adage that every person is an island would then take on a different, more affirmative, meaning. What this might mean for our understanding of health and disease is then a topic for philosophical (and perhaps also artistic) reflection and experimentation.
Gilbert also calls attention to the role of social interaction as a vehicle for sharing microbial communities.   He points for instance to the way that baboons physically interact with one another through social grooming: think of monkeys removing ticks from one another’s body or cats licking each other. One can think of these interactions as mechanisms for building a sense of shared community among animals. But physical interaction is also a way to share potentially beneficial micro-organisms, some of which could be specific to individual animals, across the community. So physical interaction would then be a form of sharing, and one that performs beneficial functions for the community. The point extends to human animals. Close physical contact among human family members, for instance, generates an alignment of their microbes.
Photo credit: Muhammad Mahdi Karim (original photograph), Papa Lima Whiskey (derivative edit)
There is more than sharing the same family household. Sharing artificial human-made spaces, for instance coffee shops or theatres, also performs a similar function. A critical component of our interaction with micro-organisms, then, is the role of our shared artificial built environment. Other researchers have suggested the role of our interaction with our built environment in building our microbial repertoires and our immunity: “choices in architectural design and building materials can significantly affect the microbial communities we interact with on a daily basis…”  Just as Sigerist referred to the “cultural morphology of disease”, we can speak of the cultural morphology of our microbial signatures.
Is this extended microbial sharing, in the context of a built environment, always a good idea? Faced with the Covid-19 pandemic, we might not be sure. Gilbert himself expresses doubts: “there is now mounting evidence to suggest that the over-sharing of the microbiome may be reducing our exposure to richer microbiomes from other sources, thereby limiting the development of our immune system.”  However we evaluate the impact of our built environment on our microbial signatures. Simon Lax, Catherine Nagler and Jack Gilbert have emphasised the importance of studying carefully the microbial signatures of specific locations, for instance hospitals, schools, or prisons.  Citizen science here also plays a potential role, as people are enlisted in the project of coming to understand the microbial signatures of the sites that they inhabit.
The question of citizen participation in science also suggests questions about the nature of democracy and the organization of a cooperative society. Such questions lie at the heart of any enterprise that recognises the interplay of the social and the biological today. These questions are closely connected to the question of the ways in which we choose to frame disease, but also to the ways in which we choose to frame ourselves and our spatio-temporal, communal being as organisms, super-organisms, as beings who dwell and beings wherein others dwell. (first drafted on 19 May 2020, Hong Kong, updated 19 August 2022)
 Gilbert, Jack 2015: “Our unique microbial identity,” Genome biology vol. 16,1 97. 14 May.
 See .
 Zhu, Ana; Sunagawa, Shinichi; Mende, Daniel R.; and Bork, Peer 2015: “Inter-individual differences in the gene content of human gut bacterial species,” Genome Biol 16.
 See .
 Gilbert,Jack A. 2015: “Social behavior and the microbiome,” eLife vol. 4 e07322. 31 March.
 Tung, Jenny et al. 2015: “Social networks predict gut microbiome composition in wild baboons.” eLife vol. 4 e05224. 16 March.
 Lax, Simon et al. 2015: “Our interface with the built environment: immunity and the indoor microbiota,” Trends in immunology vol. 36,3, pp. 121-3.
 See .
 See for instance: Marwa T. Elrakaiby, Soha Gamal-Eldin, Magdy A. Amin, and Ramy K. Aziz, ”Hospital Microbiome Variations As Analyzed by High-Throughput Sequencing,” OMICS: A Journal of Integrative Biology. Sept 2019, pp. 426-438.