Monitoring the microbial burden in manned space stations

Abstract

An impaired immunity generally weakens the host defense against microbial challenges and increases the vulnerability to infection. Especially in space, the consequences of an impaired immune system can further aggravate as astronauts, spending 100% of their time enclosed, face multiple stressors in an artificial environment with its own microbial population and dynamics. In this chapter, the knowledge of the environmental microbial burden in manned space stations and, in particular, the International Space Station ISS will be reviewed in terms of level and diversity. The implemented quality standards and monitoring strategies will be discussed in relation to the microbial burden and its impact on the crew’s well-being and ship safety. The consequences of impaired immunity to cope adequately with microbial contamination will increase the risk of infections in general and thereby endanger mission success. Microbial environmental quality and hazard control is therefore crucial to assure crew health. This might become even more important (1) when supplies from Earth are very restricted (cis-lunar stations or moon habitats) or almost impossible while on a mission to Mars and (2) since the interactions between the microbial environment, the human microbiome, and immune functions are receiving more attention and becoming more evidence-based.