New Delhi: NASA's Indian-origin astronaut Sunita Williams, along with eight other crew members aboard the International Space Station (ISS), are facing a new challenge as a superbug has been discovered within the orbiting station, posing a potential threat to the astronauts currently living there.

Scientists have discovered a type of bacteria called 'Enterobacter bugandensis' which has evolved and become more potent in the closed environment of the ISS. This multi-drug resistant bacteria, often referred to as a 'superbug,' can infect the respiratory system. Spacebugs are not alien life forms; they are bacteria that hitched a ride to the ISS as hidden co-passengers with the crew.

Earlier in April, NASA said, “In a new scientific paper funded by an Ames Space Biology grant, Principal Investigator Dr. Kasthuri Venkateswaran of NASA’s Jet Propulsion Laboratory strains of the bacterial species Enterobacter bugandensis isolated from the International Space Station (ISS) were studied.”

Williams and her colleague Barry Eugene "Butch" Wilmore arrived at the ISS on the new Boeing Starliner spacecraft on June 6, 2024. They are expected to stay for over a week before returning to Earth. Other astronauts often spend longer periods at the ISS, however, given the limited health facilities, the discovery raises concerns about the well-being of astronauts traveling to the space station.

The seven other crew members have been living on the ISS for a longer period. Usually, the primary concern at the ISS has typically been flying space debris and micrometeorites, however, the emergence of bacteria that have traveled as co-passengers and evolved during the 24 years of continuous habitation on the space station is now a major concern.

Research findings revealed that the ISS-isolated strains of the bacterial species E. bugandensis have become genetically and functionally distinct from their Earth counterparts.

According to the NASA website, "Thirteen strains of E. bugandensis, a bacterium notorious for being multi-drug resistant, were isolated from the ISS. Study findings indicate under stress, the ISS isolated strains were mutated and became genetically and functionally distinct compared to their Earth counterparts".

"The strains were able to viably persist in the ISS over time with a significant abundance. E. bugandensis coexisted with multiple other microorganisms, and in some cases could have helped those organisms survive," the website added.

The environment aboard the ISS presents astronauts with unique health challenges due to its extreme differences from Earth. Consequently, studying the microbes present on the space station holds paramount importance for ensuring the well-being of astronauts and for planning future space missions. 

Researchers emphasize that astronauts, operating under altered immune conditions and with limited access to traditional medical facilities, face distinctive health hurdles during their time in space. Understanding the microbial landscape aboard the ISS is crucial for assessing the impact of these microorganisms on astronaut health and for mitigating potential risks associated with long-duration space travel.

According to BioSpectrum India, Dr Kasthuri Venkateswaran, Senior Research Scientist at JPL, NASA, said, "Our research uncovers how certain benign microorganisms help to adapt and survive opportunistic human pathogen, E. Bugandensis, in the unfavourable conditions of the International Space Station."

Dr Venkateswaran further explained what the implications of this study would be for the health of astronauts. He said, “The knowledge gained from this study would shed light on microbial behaviour, adaptation, and evolution in extreme, isolated environments that allow in designing novel countermeasure strategies to eradicate opportunistic pathogens, thus protecting the health of astronauts.”

Boeing’s Starliner capsule 

White with black and blue trim, Boeing's Starliner capsule is about 10 feet (3 meters) tall and 15 feet (4.5 meters) in diameter. It can fit up to seven people, though NASA crews typically will number four. The company settled on the name Starliner nearly a decade ago, a twist on the name of Boeing’s early Stratoliner and the current Dreamliner planes.

THE CREW

Veteran NASA astronauts Butch Wilmore and Suni Williams are retired Navy captains who spent months aboard the space station years ago. They joined the test flight after the original crew bowed out as the delays piled up. Wilmore, 61, is a former combat pilot from Mount Juliet, Tennessee, and Williams, 58, is a helicopter pilot from Needham, Massachusetts.