Space travel makes lethal bacteria more deadly

It has been found that bugs intentionally taken into space on board the United States’ space shuttle Atlantis became three times more deadly than those cultivated on Earth.

Scientists in the United States say that the results are relevant for future space travel, particularly since missions are now being planned further afield and for much longer periods.

They also say that their work could also have applications in the treatment of infectious diseases on Earth.

When Atlantis lifted off on a 12-day mission in September 2006, it carried six astronauts and some salmonella typhimurium, bacteria that is often fatal in humans.

Salmonella, usually a culprit in food poisoning, can cause vomiting, fever, diarrhea, and abdominal cramps. Most types of salmonella, which can grow on most foods, are fatal in the elderly or young if left untreated.

The bacteria were part of an experiment led by researchers from Arizona State University.

During the 12-day mission, one of the astronauts activated the growth of the bacteria. When the mission returned, the bugs were compared with a control batch cultured on Earth.

The ‘space bugs’ were found to be three times as deadly to mice as the control bugs, according to Cheryl Nickerson, an associate professor at the Centre for Infectious Diseases and Vaccinology at Arizona State University and lead author of the study.

Researchers found that 167 genes had changed in the salmonella that went to space, possibly due to a force called fluid shear.

Prof Cheryl Nickerson said that deepening understanding of how the bacteria react in certain situations could also have applications in the treatment of infectious diseases on Earth.

She added: “The new insight that we are gaining from culturing these bacteria opens up the possibility that we can identify new targets that have a real potential to be translated to a clinical application, perhaps as a new drug or therapeutic or vaccine to treat the infections, whether it is for astronauts or for space tourists, or for us here on Earth.”

The astronaut who carried out the experiment on board Atlantis had collapsed during a ‘welcome home’ ceremony from the mission. Experts at the National Aeronautics and Space Administration (NASA) attributed that to her adjusting to gravity.

Prof Cheryl Nickerson said the incident was totally unrelated to the astronaut’s work with the bacteria. She explained: “At no time were the crew at any risk – this experiment was properly contained in triple containment levels for their safety. Nor was anyone on the ground, or nor is anyone on the ground in any risk for these bacteria.”