NCIt definition : Infection caused by an organism that is capable of causing disease in immunocompromised
patients only (e.g. HIV-positive or transplanted patients).--2004;
Alternative definition : NICHD: An infection that occurs in an immunocompromised host, but that does not usually
cause an infection with similar frequency or severity in a normal (immunocompetent)
host.; NCI-GLOSS: An infection caused by an organism that does not normally cause disease.
Opportunistic infections occur in people with weakened immune systems.;