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U.S. Department of Health and Human Services


Self-Study Modules for Effective TB Interviewing


Associate a person who has been identified by the index patient in a source case investigation as someone with whom he or she spends prolonged, frequent time. A person who is somehow affiliated with a patient who has noninfectious tuberculosis or another contact, often used in connection with source-case investigations.

Outbreak a greater-than-normal or greater-than-expected number of individuals infected or diagnosed with suspected or verified TB in a given period of time or a particular place.

Proxy a person who is interviewed in the place of the index patient; proxies can be family members or close friends. A proxy is used if the patient is deceased, physically or mentally hindered, very young, uncooperative, or unable to be located.

Restriction fragment length polymorphism (RFLP) analysis A method of DNA fingerprinting, which can be used to identify specific strains of M. tuberculosis and, thus, track TB transmission during outbreaks.

Social network linkage of persons or places where TB is spread through shared air space and common ties (e.g., social) amongst the persons and settings involved.

Social network analysis looking at routinely collected interview data to find common links amongst both cases and infected persons; these links may be persons or places.

Source case a person with infectious TB disease who is responsible for spreading
M. tuberculosis to another person or persons.

Source case investigation the process of conducting a public health investigation to determine who may have transmitted M. tuberculosis to a patient when recent

transmission is reported. Source case investigations can be applied to both recent transmissions in infected adults and children and for disease in very young children.

Undocumented the term used to describe a person who is not in the country on a valid visa.


Released October 2008
Centers for Disease Control and Prevention
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
Division of Tuberculosis Elimination -

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CDC/Division of Tuberculosis Elimination
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