What Happened To Everyone Who Wore A Symbiote?

Cletus Kasady was essentially personalised to hold the Carnage symbiote - with the serial killer being strangled by his own umbilical cord in the womb, only to be brought back from the dead by the evil god Knull - who coincidentally was also the creator of the symbiotes.

So when the Venom symbiote creates an offspring - during the strange stint of time where Cletus and Brock roomed together in prison - the new creature immediately bonds to Kasady, turning the already unstable murderer into a catastrophic threat.

Cletus is currently still bonded to the symbiote after he pair were brought back to life by Knull's cult - meaning that the already dead human host may pass away if he is separated from his alien pal.