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. 2007 Dec;6(12):2169-74.
doi: 10.1128/EC.00308-07. Epub 2007 Oct 19.

Accidental virulence, cryptic pathogenesis, martians, lost hosts, and the pathogenicity of environmental microbes

Arturo Casadevall  1 , Liise-anne Pirofski
Affiliations

Accidental virulence, cryptic pathogenesis, martians, lost hosts, and the pathogenicity of environmental microbes

Arturo Casadevall et al. Eukaryot Cell. 2007 Dec.
No abstract available

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Figures

FIG. 1.
FIG. 1.
Disease as a function of microbial burden as viewed from the damage response framework of microbial pathogenesis (5). (A) For host-microbe interactions resulting in the commensal state, there is a relatively constant microbial population over time that is maintained in its ecological niche by competition with other microbes and host defense (left panel). In the state of commensalism, the intensity of the immune response is such that it minimizes damage from the host-microbe interaction (middle panel), over time (right panel), and the damage incurred by the host is below the threshold for disease (dotted line). (B) When host-microbe interactions are perturbed, the microbial burden can increase (left panel), triggering a stronger immune response that can damage the host (middle panel) and eventually result in disease over time (right panel). The diagrams in panel B are what might be expected when a person takes antibacterial drugs and develops mucosal candidiasis. The drugs kill bacteria and perturb the ecological site, resulting in a proliferation of Candida spp. that elicits a stronger immune response, which in turn brings forth inflammation that causes sufficient damage to produce symptoms of disease.
See this image and copyright information in PMC

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