These are called opportunistic pathogens. They may normal gut bacteria like e. coli, but when it enters the bloodstream or travels up your urethra to your kidneys they will kill you.
Now some of these bacteria may stay put either because they are inhibited by competing bacteria which is why some research focuses on transplating gut microbiome, but sometimes bacteria wait until they have enough around for a massive attack through quorum sensing.
Jimmy_Smith t1_iujz6c0 wrote
Reply to comment by WasabiSteak in How do white blood cells know in which direction there is a bacteria? by Enocli
These are called opportunistic pathogens. They may normal gut bacteria like e. coli, but when it enters the bloodstream or travels up your urethra to your kidneys they will kill you.
Now some of these bacteria may stay put either because they are inhibited by competing bacteria which is why some research focuses on transplating gut microbiome, but sometimes bacteria wait until they have enough around for a massive attack through quorum sensing.