opportunistic infection

infection /in·fec·tion/ (-fek´shun)

1. invasion and multiplication of microorganisms in body tissues, especially that causing local cellular injury due to competitive metabolism, toxins, intracellular replication, or antigen-antibody response.

2. an infectious disease.

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airborne infection  one that is contracted by inhalation of microorganisms or spores suspended in air on water droplets or dust particles.

droplet infection  infection due to inhalation of respiratory pathogens suspended on liquid particles exhaled by someone already infected (droplet nuclei) .

endogenous infection  that due to reactivation of organisms present in a dormant focus, as occurs in tuberculosis, etc.

tunnel infection  subcutaneous infection of an artificial passage into the body that has been kept patent.

opportunistic infection  infection by an organism that does not ordinarily cause disease but becomes pathogenic under certain circumstances (e.g., impaired immune responses).

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opportunistic infection

n.

An infection by a microorganism that normally does not cause disease but becomes pathogenic when the body's immune system is impaired and unable to fight off infection, as in AIDS and certain other diseases.

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Opportunistic infection

An infection that is normally mild in a healthy individual, but which takes advantage of an ill person's weakened immune system to move into the body, grow, spread, and cause serious illness.

Mentioned in: AIDS, AIDS Tests, Cryptococcosis, Mucormycosis, Progressive Multifocal Leukoencephalopathy

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opportunistic infection

Etymology: L, opportunus, convenient, icus, form

1 an infection caused by normally nonpathogenic organisms in a host whose resistance has been decreased by disorders such as diabetes mellitus, human immunodeficiency virus (HIV) infection, or cancer; a surgical procedure such as a cerebrospinal fluid shunt or a cardiac or urinary tract catheterization; or immunosuppressive drugs. Long-term use of antibiotics or other drugs may also affect the immune system, creating opportunity for microorganisms not usually pathogenic to become pathogens. People with HIV are particularly susceptible to such infections.

2 an unusual infection with a common pathogen, such as cellulitis, meningitis, or otitis media.

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opportunistic infection,

n an infection by a microbial organism to which the patient is usually resistant; however, because of reduced vitality or through suppression of the immune system, the patient has become infected.

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infection

1. invasion and multiplication of microorganisms in body tissues, especially that causing local cellular injury due to competitive metabolism, toxins, intracellular replication or antigen-antibody response.

2. an infectious disease.

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acute infection

short duration, of the order of several days.

airborne infection

infection by inhalation of organisms suspended in air on water droplets or dust particles.

arrested infection

restrained in its development by a capsule or adhesion but still containing infective material.

chronic infection

long duration, of the order of weeks or months.

infection control

the utilization of procedures and techniques in the surveillance, investigation and compilation of statistical data in order to reduce the spread of infection, particularly nosocomial infections.

cross infection

infection transmitted between patients infected with different pathogenic microorganisms.

droplet infection

infection due to inhalation of respiratory pathogens suspended on liquid particles exhaled by an animal that is already infected.

dustborne infection

infection by inhalation of pathogens that have become affixed to particles of dust.

endogenous infection

that due to reactivation of organisms present in a dormant focus, as occurs in tuberculosis, etc.

exogenous infection

that caused by organisms not normally present in the body but which have gained entrance from the environment.

general infection

see systemic infection (below).

latent infection

the animal is infected but there are no clinical signs nor infectious agent detectable in discharges.

local infection

has a common syndrome of varying degree, depending on the site and acuteness of the lesion and the type of microorganisms present, including fever, toxemia and leukocytosis with a left shift. The specific individual signs relate to the location of the lesion and the pressure it exerts on nearby organs. See also abscess, cellulitis, phlegmon, osteomyelitis, omphalophlebitis, empyema, adenitis, metritis, mastitis, periphlebitis.

masked infection

an infection is known to occur but the infectious agent cannot be demonstrated, e.g. the sheep-associated malignant catarrhal fever virus.

mixed infection

infection with more than one kind of organism at the same time.

nosocomial infection

pertaining to or acquired in hospital.

opportunistic infection

infection with organisms which are normally harmless but become pathogenic when the body's defense mechanisms are compromised.

patent infection

one in which the infectious agent can be demonstrated in discharges of the patient.

persistent infection

a characteristic of some viruses, particularly herpesviruses and lentiviruses, in which there may be long-lasting or life-long latent infections, with asymptomatic periods and recurring acute episodes of clinical disease (herpesviruses) or onset of severe clinical disease (lentiviruses).

pyogenic infection

infection by pus-producing organisms.

secondary infection

infection by a pathogen following an infection by a pathogen of another kind.

infection stones

see struvite urolith.

subclinical infection

infection associated with no detectable signs but caused by microorganisms capable of producing easily recognizable diseases, such as mastitis or brucellosis; often detected by the production of antibody, or by delayed hypersensitivity exhibited in a skin test reaction to such antigens as tuberculoprotein.

super infection

a second infection occurs in an animal which is already experiencing an infection with another agent.

systemic infection

the infection is widespread throughout the body and must be assumed to be in all organs.

terminal infection

an acute infection occurring near the end of a disease and often causing death.

transmissible infection

an infection capable of being transmitted from one animal to another. Called also contagious.

waterborne infection

infection by microorganisms transmitted in water.

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opportunistic infection

Infectious disease An infection by a microorganism, usually bacterial, that is part of the normal flora–eg, of the skin, GI tract, GU tract, respiratory tract or elsewhere, which becomes pathogenic when the host's immune system is compromised by an unrelated disease–eg, AIDS, chemotherapy, or DM, resulting in OIs of lungs, brain, eyes, etc