In the manned space environment, there is almost no influence from the external environment.In addition, since there is no gravity, fungal spores and the like float in the air together with attached particles, which may adhere to the aviator's skin (particularly the upper body) and increase the amount of suction to the lungs.Therefore, this time, we investigated the situation of fungal inhalation by astronauts.

　Of the astronauts who stayed at the International Space Station, 2 people stayed for 10 weeks, 10 people stayed for 1 months, and 1 person stayed for 21 year, for a total of XNUMX people before departure.・ Collected during the stay and after returning.

　The fungi found in the collected samples changed from 43 strains of 120 genera during the stay on the ground to 4 strains of 18 genera during the stay on the ISS. Environmental fungi were isolated from 2 out of 10 people before departure for both 8-week and half-year residents, but the number of species and strains decreased significantly compared to before departure. Only one strain of filamentous fungus and one strain of yeast were isolated during the stay from one-year residents. The clean air environment inside the ISS may have affected it.

　In addition, for those who stayed for half a year, the number of bacteria decreased when the second collection was taken during the stay after a period of one month or more. After returning to the ground, the two-week residents returned to the strains and strains before departure. It is possible that the length of stay on the ISS, the exposure time of the fungus on the ground, and the difference in the environment after returning to the ground affected the transition of the fungus.

　This time, there were no strains that immediately affected the health of astronauts, but since bacteria related to allergies are also included, continued investigation is needed in the future.

Paper information:[Microbiology and Immunology] Identification of fungi isolated from astronaut nasal and pharyngeal smears and saliva