Planetary Protection is the practice of protecting solar system bodies from contamination by Earth life and protecting Earth from possible life forms that may be returned from other solar system bodies. NASA’s Office of Planetary Protection promotes the responsible exploration of the solar system by implementing and developing efforts that protect the science, explored environments and Earth.
NASA’s Planetary Protection policies and requirements ensure safe and verifiable scientific exploration for extraterrestrial life. The main objectives are to
Carefully control forward contamination of other worlds by terrestrial organisms and organic materials carried by spacecraft in order to guarantee the integrity of the search and study of extraterrestrial life, if it exists.
Rigorously preclude backward contamination of Earth by extraterrestrial life or bioactive molecules in returned samples from habitable worlds in order to prevent potentially harmful consequences for humans and the Earth’s biosphere.
Always wear protection, or you’ll infest the whole solar system
humans here are more like crab louse and there’s no protection against them
https://en.wikipedia.org/wiki/J._Nick_Benardini
https://sma.nasa.gov/sma-disciplines/planetary-protection