On a long spaceflight, it could be easy for microbes to get out of control. Microgravity weakens the immune system in some ways while it also increases the virulence and antimicrobial resistance of some microorganisms.
Meanwhile, without gravity, germs launched by coughs and sneezes no longer fall to the ground within an earthly three to six feet, but continue to float around, increasing the distance and time for astronauts to inhale them or for them to settle on a wider variety of surfaces.
A new paper published in the journal Clinical Infectious Diseases brings together a broad base of research designed to keep astronauts healthy in deep space.
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