In epidemiology,<unk>  is the ability of a pathogen to establish an infection. More specifically,<unk>  is a pathogen's capacity for horizontal transmission — that is, how frequently it spreads among hosts that are not in a parent–child relationship. The measure of<unk>  in a population is called incidence.<unk>  has been shown to positively correlate with virulence, in plants. This means that as a pathogen's ability to infect a greater number of hosts increases, so does the level of harm it brings to the host. A pathogen's<unk>  is subtly but importantly different from its transmissibility, which refers to a pathogen's capacity to pass from one organism to another.
Infectivity
Drug resistance
Parasitism
Convalescence
Immunocompetence
Antimicrobial resistance
Vaccine resistance
Resistance 