Could a meteorite carry dangerous germs from space?
There is no evidence that meteorites carry living organisms from space, let alone harmful ones. Germs on meteorites come from Earth after they land.
It is a common theme in science fiction, but there is no evidence that meteorites carry life from space.
What scientists have found. Meteorites contain organic molecules, such as amino acids, but no living organisms or fossils have been convincingly identified. Claims of microfossils in meteorites, such as in the Martian meteorite ALH 84001 in 1996, have not been accepted by most scientists, because non-biological processes can explain the features.
Hostile journey. Space is extremely hostile to life, with vacuum, extreme cold and intense radiation. Most meteorites spend millions of years in space. Entry into Earth's atmosphere heats their surfaces intensely, though interiors remain cool. Some research has explored whether microbes could survive such journeys, a hypothesis called panspermia, but this remains speculative.
Earth germs. Once a meteorite lands, it is quickly colonised by bacteria and fungi from soil, water and air, just like any rock. Studies have found Earth microbes living inside some meteorites. These are ordinary environmental microbes.
Hygiene. As with any rock, wash your hands after handling meteorites, especially those found in soil. Do not put them in your mouth.
Sample return missions. For samples brought back from places that might have hosted life, such as Mars, space agencies plan strict containment to avoid any risk, called planetary protection. Samples from asteroids, such as Ryugu and Bennu, were judged to have negligible risk, but were handled in clean conditions mainly to protect the samples from contamination by Earth.
In short, meteorites are safe from space germs; normal hygiene is all that is needed.