NASA has confirmed that five strains of antibiotics-resistant bacteria called Enterobacter bugadensis have been identified onboard the International Space Station.
In a recently published study, researchers from the Jet Propulsion Laboratory investigated the five strains of Enterobacter, which were discovered on the toilet and exercise platforms on March 2015 as part of the effort to characterize the bacterial community that thrives within the space station.
Superbugs On The ISS
To get a better understanding of the bacteria, the researchers compared the five strains found in the ISS to all publicly available genomes of Enterobacter on Earth. They concluded that the ISS Enterobacter strains are most similar to three clinical opportunistic infectious organisms collected in a few hospital settings.
Kasthuri Venkateswaran, senior research scientist at the Jet Propulsion Laboratory's Biotechnology and Planetary Protection Group, said that the three strains from Earth infect immunocompromised patients, including in the United States. In addition, the strains of Enterobacter on Earth are also known to be highly resistant to antibiotics.
Strains Of Bacteria In The ISS Not Dangerous
However, the researchers revealed that the strains of Enterobacter found in the ISS were not pathogenic to humans. The astronauts on board are not in danger of being infected, but its presence alone on the orbital outpost has concerning implications.
"Given the multi-drug resistance results for these ISS E. bugandensis genomes and the increased chance of pathogenicity we have identified, these species potentially pose important health considerations for future missions," stated Nitin Singh, first author of the study. "However, it is important to understand that the strains found on the ISS were not virulent, which means they are not an active threat to human health, but something to be monitored."
The researchers used computer analysis and found that the organisms in the ISS still have 79 percent probability that they might cause diseases. Further analyses of the bacteria involving a variety of factors, including the conditions onboard the orbiting outpost, need to be carried out to confirm.
NASA regularly examines the microbe samples onboard the ISS to monitor if they pose danger to the crew and to see how the environment affects the population. The study was published in the open-access journal BMC Microbiology.