Ecology is Us

Health and disease in a post-modern world

“The fault, dear Brutus, is not in our stars, but in ourselves, that we are underlings.” William Shakespeare’s Julius Caesar

Pathogens are everywhere. We are all familiar with the cold viruses that give us sniffles, coughs, and aches, and with more frightening pathogens that cause diseases such as AIDS, malaria, and tuberculosis, killing millions of people each year. But pathogens affect much more than our own health. Farmers struggle with fungi that attack their crops, forest service personnel worry about endangered species and the impact of epidemics on fragile plant communities, and tourists are increasingly finding their favorite snorkeling destinations devastated by coral bleaching diseases. Yet wiping out harmful pathogens is an unrealistic goal, and many other pathogens play positive roles in ecosystems from recycling nutrients to increasing biological diversity. In other words, pathogens are embedded within ecological systems including the eco wonderland known as the human body.

Infectious diseases involve interactions between at least two species, the pathogen and the host species it infects and many pathogens are transmitted from host to host by at least one species of vector, such as mosquito. Understanding the dynamics of any particular disease system, then, involves understanding the often, complex system of interactions among the organisms most directly involved in disease transmission. This said, an ecological view would seem a natural ally (perspective) to health specialists attempting to prevent or alleviate human suffering from disease. Yet, for all its glory, the modern medical system all but ignores an ecological perspective on disease and outright dismisses in many cases the role of evolutionary ecology, even though it underpins nearly all of human biology and thus the key to optimal health and well-being. The need to integrate these disciplines along with the role of the food supply in heath and disease is the reason we launched NakedPizza and the reason we believe the fast food industry can be a force of good in the world rather than a hazard.

The ecological management of disease among humans can be grouped into macro and micro perspectives. For example, more than 75% of emerging human pathogens are zoonotic (i.e., transmitted to humans from other animals). An unfortunate example of this is E. coli 0157:H7, the potentially fatal pathogen associated with tainted beef and produce that originates via an imbalance between feed sources and overuse of antibiotics among feedlot cattle. By changing the natural ecology of cows — from range fed to corn fed — we have tinkered with the ecological complexity and transmission of this specific pathogen by providing an ecological niche that it can exploit among the overcrowded feed lots that dot the landscape. In addition, climate change has been associated with an increase in the frequency, distribution, and severity of many infectious diseases worldwide, demonstrating ecological impacts on pathogen dynamics.

The ability of ecological approaches to inform disease prevention and management is nicely demonstrated by the number of Lyme disease cases that can be predicted almost two years in advance simply by monitoring annual acorn production. As another example, planting a diversity of rice strains rather than a monoculture has been shown to increase yields and reduce rates of infection with fungal rice blast in China.

As our species plows forward we are clearly changing the macro ecology of the world in ways that are creating opportunities for pathogens in a world that previously functioned in a state of nested equilibrium, more or less. In our post-modern world, we continue to evolve, but so do our diseases. Some diseases that were once rare have become common, others have disappeared, and new varieties have emerged. Though virtually unknown among our ancestors, today we suffer from heart disease, diabetes, hypertension, obesity, cancer, autism, Alzheimer’s, asthma, and irritable bowels. All of these diseases have emerged in the wake of important transformations between human societies and their natural, nutritional, social, and created environments. From this ecological perspective a reasonable hypothesis to explain the appearance and disappearance of disease is that changes in human and nutritional ecology result in changes in the microbes that populate our bodies and that diseases succeed and fail in response to humanity’s advances.

Any honest attempt to alleviate suffering among human populations will require (re)establishing our symbiotic relationship with the microbes who rule our world, the food that nourishes them and us, and the marriage of ecology and disease biology. We think we can make a difference. Join us friendo and believe.