A<unk><unk>  is a<unk>  cell or cluster of<unk>  cells that can be transferred between individuals without the involvement of an infectious agent, such as an oncovirus. Transmission of<unk>  between humans is rare. The evolution of<unk><unk>  has occurred naturally in other animal species, but—similarly to human<unk>  transmission—is rare.
Clonally transmissible cancer
Behavior-altering parasite
Criminal transmission of HIV
Immunization during pregnancy
Finnish heritage disease
Immune tolerance in pregnancy
Asymptomatic carrier
Opportunistic infection