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Reported Tuberculosis in the United States, 2018
Genotype Clusters
TB genotyping uses laboratory-based analyses to characterize a small portion of the genetic material of bacteria belonging to the Mycobacterium tuberculosis complex.
TB genotype clusters are defined in this report as ≥2 cases with matching genotypes in the same county or county equivalent area during a 3-year time period. Clusters are classified into alert levels on the basis of a log-likelihood ratio (LLR) calculation; clusters with an LLR of 5–<10 are classified as a medium alert level, and clusters with an LLR ≥10 are classified as a high alert level.
Cases that are part of the same genotype cluster are more likely to be related by transmission.
- TB Genotyping Surveillance Coverage: U.S. 2004–2018
- TB Genotyping Surveillance Coverage: U.S.-Affiliated Areas, 2004–2018
- Mycobacterium bovis by Origin of Birth: 2004–2018
- Characteristics of TB Cases in GENType Clusters, by Alert Levels: 2016–2018
- TB Clusters by Size: 2016–2018
- Most Frequently Reported GENTypes: U.S., 2016–2018
- Most Frequently Reported GENTypes: U.S.-Affiliated Areas, 2016–2018
- Genotyping Surveillance Coverage: Reporting Areas, 2018