Reported Tuberculosis in the United States, 2017

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Table 24. Characteristics of Tuberculosis Cases in GENType Clusters1, by Alert Levels Based on Log-Likelihood Ratios (LLR)2: United States, 2015–2017

Table 24. Characteristics of Tuberculosis Cases in GENType Clusters, by Alert Levels Based on Log-Likelihood Ratios (LLR): United States, 2015-2017
Case Characteristics Unique Clustered   Alert Levels for Clustered Cases3
Non-alerted (LLR <5) Medium (LLR 5 – <10) High  (LLR ≥10)
No. (%) No. (%) No. (%) No. (%) No. (%)
Total 16,770 79.7 4,259 20.3 2,473 58.1 1,036 24.3 750 17.6
Origin of Birth
U.S-born 4,169 65.7 2,179 34.3 869 39.9 664 30.5 646 29.6
Non-U.S.–born 12,585 85.9 2,072 14.1 1,598 77.1 371 17.9 103 5.0
Unknown or Missing 16 66.7 8 33.3 6 75.0 1 12.5 1 12.5
Race and Ethnicity
Hispanic or Latino 4,524 77.4 1,323 22.6 823 62.2 355 26.8 145 11.0
American Indian/Alaska Native 133 46.5 153 53.5 17 11.1 51 33.3 85 55.6
Asian 6,608 86.8 1006 13.2 868 86.3 108 10.7 30 3.0
Black or African American 3,075 72.2 1,185 27.8 500 42.2 325 27.4 360 30.4
Native Hawaiian/Other Pacific Islander 123 63.4 71 36.6 43 60.6 10 14.1 18 25.4
White 2,144 81.6 483 18.4 207 42.9 172 35.6 104 21.5
Multiple Race 116 80.6 28 19.4 9 32.1 11 39.3 8 28.6
Unknown or Missing 47 82.5 10 17.5 6 60.0 4 40.0 0 0.0
Age Group (Years)
0–4 85 43.1 112 56.9 49 43.8 42 37.5 21 18.8
5–14 116 61.1 74 38.9 42 56.8 16 21.6 16 21.6
15–24 1,554 76.1 488 23.9 282 57.8 129 26.4 77 15.8
25–44 5,056 78.8 1,361 21.2 746 54.8 370 27.2 245 18.0
45–64 5,060 76.8 1,525 23.2 859 56.3 348 22.8 318 20.9
≥65 4,894 87.5 699 12.5 495 70.8 131 18.7 73 10.4
Unknown
Disease Site
Pulmonary Only 11,889 77.8 3,399 22.2 1,923 56.6 843 24.8 633 18.6
Extrapulmonary 2,911 87.5 415 12.5 279 67.2 92 22.2 44 10.6
Both 1,961 81.6 442 18.4 269 60.9 101 22.9 72 16.3
Unknown 9 75.0 3 25.0 2 66.7 0 0.0 1 33.3
Sputum Smear 
Positive 7,555 76.6 2,312 23.4 1,285 55.6 621 26.9 406 17.6
Negative 6,815 82.2 1,478 17.8 914 61.8 292 19.8 272 18.4
Not Done 2,378 83.6 467 16.4 273 58.5 122 26.1 72 15.4
Unknown or Missing 22 91.7 2 8.3 1 50.0 1 50.0 0 0.0
Cavitary Disease4
Yes 154 76.2 48 23.8 25 52.1 14 29.2 9 18.8
No 1,386 81.0 326 19.0 200 61.3 73 22.4 53 16.3
Unknown or Missing
Homeless Within Past Year
Yes 628 56.8 478 43.2 195 40.8 119 24.9 164 34.3
No 16,051 81.0 3,757 19.0 2,264 60.3 909 24.2 584 15.5
Unknown or Missing 91 79.1 24 20.9 14 58.3 8 33.3 2 8.3
Excess Alcohol Use Within the Past Year
Yes 1,385 62.7 823 37.3 329 40.0 254 30.9 240 29.2
No 15,157 81.8 3,370 18.2 2,102 62.4 762 22.6 506 15.0
Unknown or Missing 228 77.6 66 22.4 42 63.6 20 30.3 4 6.1
Injecting Illicit Drug Use Within Past Year
Yes 170 59.9 114 40.1 42 36.8 42 36.8 30 26.3
No 16,410 80.1 4,067 19.9 2,380 58.5 973 23.9 714 17.6
Unknown or Missing 190 70.9 78 29.1 51 65.4 21 26.9 6 7.7
Non-Injecting Illicit Drug Use Within Past Year
Yes 877 57.5 649 42.5 260 40.1 195 30.0 194 29.9
No 15,704 81.6 3,537 18.4 2,167 61.3 821 23.2 549 15.5
Unknown or Missing 189 72.1 73 27.9 46 63.0 20 27.4 7 9.6
Resident of a Correction Facility at the Time of Diagnosis
Yes 463 70.2 197 29.8 94 47.7 50 25.4 53 26.9
No 16,192 80.1 4,018 19.9 2,353 58.6 970 24.1 695 17.3
Unknown or Missing 115 72.3 44 27.7 26 59.1 16 36.4 2 4.5
HIV Status
Positive 809 76.0 255 24.0 135 52.9 56 22.0 64 25.1
Negative 14,089 79.4 3,660 20.6 2,110 57.7 908 24.8 642 17.5
Refused 397 86.3 63 13.7 46 73.0 12 19.0 5 7.9
Not Offered 991 82.2 215 17.8 136 63.3 46 21.4 33 15.3
Unknown, Missing or Indeterminate 484 88.0 66 12.0 46 69.7 14 21.2 6 9.1
Multidrug-Resistant TB
Yes 245 81.1 57 18.9 36 63.2 7 12.3 14 24.6
No 15,893 79.8 4,027 20.2 2,337 58.0 982 24.4 708 17.6
Unknown or Missing 632 78.3 175 21.7 100 57.1 47 26.9 28 16.0

1 GENType clusters have two or more cases with matching spoligotype and 24-locus mycobacterial interspersed repetitive unit-variable number tandem repeat type (MIRU-VNTR) within a county during the specified 3-year time period.
2 Alert levels are based on a log-likelihood ratio (LLR), which calculates the geographical concentration of a genotype in a county compared to the rest of the country during a 3-year period.
3 There were 4,259 cases in 1,409  alerted clusters: 750 cases were in 76 (5.4%) high alert clusters; 1,036 cases were in 335 (23.8%) medium alert clusters, and 2,473 cases were in 998  (70.8%) non-alert clusters.
4 Cavitary disease only assessed for persons with pulmonary TB and an abnormal x-ray.

Note: Case counts for race categories (American Indian/Alaska Native, Asian, black/African American, Native Hawaiian/Other Pacific Islander, and white) are mutually exclusive and do not include persons of Hispanic ethnicity or multiple race. Multiple race does not include persons of Hispanic ethnicity.

Page last reviewed: October 22, 2018