Microbial resilience in space: Biofilms, risks and strategies for space exploration

Biofilms are a community of microorganisms that can form on any surface, posing several challenges and significant medical issues. Their formation is not just limited to Earth but has also been observed in space stations and are termed as space biofilms. This is a major concern as certain biofilms can lead to high-risk compromising crew's health, while others have the capacity to corrode spacecraft and equipment, leading to instrument malfunction, which can jeopardize the mission. Additionally, the way biofilms form and behave in space is different from how they do on Earth due to microgravity. Microgravity and other space conditions intensify microbial biofilm formation, pathogenicity, and antibiotic resistance on spacecraft surfaces. This review examines spacecraft biofilms and their effects on equipment, crew health, and spacecraft. The review also discusses several key microbial species that are known to form biofilms on spacecraft. It highlights how antimicrobial coatings, biofilm disruptors, and multiple detection methods could protect space shuttle integrity and crew health during long missions. It also highlights the disruption and control strategies to mitigate and eradicate biofilms in spaceflight missions. However, significant research is still required to overcome existing challenges of studying space biofilms due to limited data, high cost and replicating space microgravity on earth. Innovative strategies are required for effective biofilm management in space, especially to address biofilm formation under microgravity, investigate antimicrobial efficacy, and to assess its health impacts on astronauts for sustainable long-term missions.