Antibiotics should be used with caution in outer space since they may quickly fuel drug resistance in bacteria, researchers report in mBio.
The researchers found Escherichia coli bacteria treated with antibiotics in a simulated microgravity environment rapidly developed resistance to antibiotics.
The bacteria was still resistant to the drugs over time even when they were no longer exposed to an antibiotic. Cells grown under the same conditions that did not get exposed to antibiotics, however, did not develop resistance.
This finding is especially concerning for astronauts, who may have suppressed immune systems due to microgravity, sleep deprivation, isolation or microbial contamination.
The risk of infection increases significantly under these conditions, and if infection occurs, it is important that the infectious agent is not antibiotic-resistant, the researchers said.
"Minimizing the occurrence of antibiotic resistance is, therefore, highly desirable," they wrote. "To facilitate this, it is important to better understand the long-term response of bacteria to the microgravity environment. This study demonstrated that the use of antibiotics as a preventive measure could be counterproductive and would likely result in persistent resistance to that antibiotic."