Opportunistic infection

Infection by organisms that rarely have serious or widespread effects in people of normal health, but which can cause serious illness or widespread infection in a person whose immune system is impaired. In most patients with AIDS, death is due to opportunistic infections, especially pneumocystis pneumonia. Many fungal infections, such as candidiasis, and some viral infections, such as herpes simplex, are opportunistic infections. Treatment is with appropriate antimicrobial drugs.