WordNet
n. the earliest documented case of a disease that is included in an epidemiological study
Wikipedia
The index case, primary case, or patient zero is the initial patient in the population of an epidemiological investigation, or more generally, the first case of a condition or syndrome (not necessarily contagious) to be described in the medical literature, whether or not the patient is thought to be the first person affected. An index case will sometimes achieve the status of a "classic" case in the literature, as did Phineas Gage.
The index case may indicate the source of the disease, the possible spread, and which reservoir holds the disease in between outbreaks. The index case is the first patient that indicates the existence of an outbreak. Earlier cases may be found and are labeled primary, secondary, tertiary, etc. "Patient Zero" was used to refer to the index case in the spread of HIV in North America.
In genetics, the index case is the case of the original patient (propositus or proband) that stimulates investigation of other members of the family to discover a possible genetic factor.
Index Case is the self-titled album by Iowan nu metal band Index Case. Released on September 27, 2005 via Mortal Music, it is the band's first commercially released album. Index Case is virtually the same album recorded for No Name/ Elektra but with slight alterations.
Index case may refer to:
- Index Case, a central point of reference in a disease outbreak.
- Index Case (band), a melodic nu metal music group.
Usage examples of "index case".
A minute later they were in Room 1, temporary home of the Index Case.
But only a handful, and you didn't start with one of those as your Index Case.
Richter was an index case and that he, and only he, had been exposed to the unknown reservoir of the virus.
I'm afraid she's going to turn out to be the index case of what could be a big outbreak.
Badri was the index case, and sometime in the four to six days before the drop he had been in contact with a reservoir.