Bioaerosol Dispersal Models and the In Silico Design of a Synthetic Strain of Bacillus subtilis with Stringent Growth Regulation

Abstract

A critical component of biodefense research is the modeling and simulation of the spread of Bacillus anthracis spores. Of the three primary approaches used to study the dispersal of such bioaerosols - mathematical modeling, physical simulation, and biological simulation - the direct dispersal of biological simulants offers the most accurate results. However, the dispersal of viable simulants risks colonization of undesired environments, such as immunocompromised persons within exposed populations. During its Cold War biological weapons research program, the US government dispersed biologically viable simulants, exposing human subjects (often unbeknownst to them) to these ostensibly safe but potentially pathogenic organisms. An analysis of these open-air tests illustrates three improvements to ensure that future biodefense research is conducted ethically: reduced pathogenicity of the biological simulant, obtaining informed consent (either standard or de facto) from potentially exposed populations, and ensuring that the unique concerns regarding military bioethics are addressed for any military service members who may be exposed.