Space makes astronauts more susceptible to infection

The research shows how the body's system for fighting off pathogens is weakened in space.

Evidence is growing about the many ways that travelling in the microgravity environment of space tampers with the human body, with new research showing how it dials down the activity of genes in white blood cells crucial to the immune system.

A study involving 14 astronauts who spent 4.5 to 6.5 months aboard the International Space Station found that gene expression in these cells, also called leukocytes, quickly decreased when they reached space and then returned to normal not long after returning to Earth, researchers said on Thursday.