Reported Tuberculosis in the United States, 2021

Recent transmission is evaluated using national TB molecular surveillance data. A case is estimated to be attributed to recent transmission if a plausible source case can be identified who: has the same M. tuberculosis genotype, has an infectious form of TB disease, resides within 10 miles of the case, is 10 years of age or older, and was diagnosed within 2 years prior to the case’s diagnosis date.

A map of the United States is displayed with state borders as well as county or county equivalent borders for those jurisdictions that had at least one genotyped TB case that could be evaluated for recent transmission during 2020–2021. Counts of cases attributed to recent transmission are shaded by county or county equivalent to depict relative numbers of cases attributed to recent transmission. All 50 states are shown; the New York City metropolitan area is represented as a zoomed in frame on the map. A total of 11 county or county equivalents (associated with large urban settings) had more than 20 TB cases attributed to recent transmission during 2020–2021.