opportunistic infection

[ ŏp′ər-tōō-nĭstĭk ]


  1. An infection by a microorganism that normally does not cause disease but does so when lowered resistance to infection is caused by the impairment of the body's immune system.

Words Nearby opportunistic infection

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for opportunistic infection

opportunistic infection

[ (op-uhr-tooh-nis-tik) ]


An infection caused by a microorganism that under normal conditions would not bring about disease. Opportunistic infections occur when the body's immune system is weakened by disease or malnutrition. (See AIDS.)

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.