index case

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Related to index case: index patient, primary case


In human genetics, the patient or member of the family that brings a family under study.
Synonym(s): index case
[L. probo, to test, prove]

index case

1. The earliest identified occurrence of a disease or disorder, usually as part of an epidemiological investigation of a patient population or a genetic study of a family.
2. The first patient who has such a disease or disorder. Also called proband, propositus.

index case

Etymology: L, indicare, to make known
(in epidemiology) the first case of a disease, as contrasted with subsequent cases. See also propositus.

index case

See Index patient, see there.

in·dex case

(in'deks kās)
The first case in the investigation of the outbreak of a potentially epidemic disease.

Index case

The first case of a contagious disease in a group or population that serves to call attention to the presence of the disease.
Mentioned in: Syphilis


in epidemiology, an animal which has the specified disease or condition which is under investigation.

case abstract
a structured summary of a case report suitable for computer entry; permits machine sorting and retrieval and leads an investigator to the original paper records on which detailed descriptions must be based.
case-control sampling
selection of cases as a sample to use in a case-control study (below).
case-control study
a retrospective, analytical, epidemiological study. A group of pre-existing cases of the disease are matched with a selected group of control animals that do not have the disease so that the presence or otherwise of an hypothesized disease determinant can be ascertained in both groups.
case fatality rate
the proportion of cases with a specified condition which die within a specified time.
case finding
the strategy of surveying a population to find the sick animals that are the foci of infection; an essential early step in the eradication of any disease.
case history
the collected data concerning an individual, contact and related animals, environment and management procedures, including any past medical history and any other information that may be useful in analyzing and diagnosing the case or for instructional or research purposes.
index case
the first case recorded in an outbreak.
case management
care of a sick animal including specific and supportive medication, surgical intervention, housing, bedding, nutrition, restraint, collection of specimens for submission to laboratory or stall-side tests.
case population
the group of animals in the total population which are sick or infected, as distinct from the control population, which are not sick or infected.
case recording
entry in records of the clinical findings of individual sick animals. May be structured or unstructured, paper or machine, with or without the accounting record for the case.


pl. indexes, indices [L.] the numerical ratio of measurement of any part in comparison with a fixed standard.

index case
the first case of a disease in a group to be brought to the attention of the clinician.
Color index
a publication of the Society of Dyers and Colorists and the American Association of Textile Chemists and Colorists, containing an extensive list of dyes and dye intermediates. Each chemically distinct compound is identified by a specific number, the CI number, avoiding the confusion of trivial names used for dyes in the dye industry. The Royal Horticultural Society, London, produces a similar document to aid in the identification of flower colors.
erythrocyte i's
see erythrocyte indices.
index Medicus
a monthly publication of the National Library of Medicine, in which the world's leading biomedical literature is indexed by author and subject.
opsonic index
a measure of opsonic activity determined by the ratio of the number of microorganisms phagocytized by normal leukocytes in the presence of serum from an animal infected by the microorganism, to the number phagocytized in serum from a normal animal.
phagocytic index
the average number of bacteria ingested per leukocyte of the patient's blood.
production index
a method of expressing production compared with a potential or target.
refractive index
the refractive power of a medium compared with that of air (assumed to be 1).
therapeutic index
originally, the ratio of the maximum tolerated dose to the minimum curative dose; now defined as the ratio of the median lethal dose (LD50) to the median effective dose (ED50). It is used in assessing the safety of a drug.
index Veterinarius
a periodic listing of all publications in the veterinary literature by the Commonwealth Agricultural Bureaux, United Kingdom. Also available on on-line data search.
vital index
the ratio of births to deaths within a given time in a population.
References in periodicals archive ?
Results in Figures 5, 6, and 7 show the percentage of occupants infected in the FEC as a function of supply flow rate and exposure period for a discrete value of the index case infectiousness.
None of the cases were positive for t(14;18), as was our index case.
Last Wednesday, the Nigerian health ministry confirmed that another nurse who treated the index case died after contacting the virus.
As part of an effort to better understand why the serum level of 2,3,4,7,8-pentaCDF for the index case was elevated, we conducted a follow-up interview to better understand his unique dietary history of consuming homegrown beef and vegetables from the TR FP.
Index cases from 685 B(O)C families were identified by the Familial Cancer Clinic of our hospital during the period 1998-2009.
Trichina infection was therefore established both from muscle biopsy in the index case and through direct examination of the bear meat by CDC.
Now we are facing a similar situation in the Middle East where some suggest camels are the host species but that is still unclear - we've clearly found the virus in a common bat species that was tested in the vicinity of the first index case.
During the Luweero outbreak, seven cases were reported in which nearly 90 percent of the victims were relatives living in the same area as the index case.
Ring chemoprophylaxis" entails containing a viral outbreak within a targeted geographic area surrounding an index case by administering a drug-in this case, oseltamivir--to everyone in the area, not just to known, close contacts.
Screening for latent TB infection and active disease Current WHO guidelines advise that all children < 5 years of age in close contact with a sputum smear-positive index case should be actively traced, screened for TB and provided with preventive chemotherapy once active TB has been excluded (1) (Fig.
In each family, variation scanning, including the full coding sequence and intron/exon boundaries of both genes, was carried out in the index case (usually the youngest affected member).
We do not know whether there is a mutant strain of VZV in Taiwan; thus this is a good index case for further study.