TABLE 3.
Cases of TB Among Persons With Reported Homelessness and a Plausible Source, United States, 2011–2016
| Area* | Genotyped Cases† | Cases Among Persons With Reported Homelessness and a Plausible Source,‡ n (%§) | Cases Among Persons With Reported Homelessness and a Plausible Source‡ Who Reported Homelessness,∥ n (%§) | No. Unique GENTypes¶ |
|---|---|---|---|---|
| National | 2349 | 874 (37) | 569 (24) | NA |
| Atlanta, GA | 77 | 59 (77) | 50 (65) | 10 |
| Chicago, IL | 35 | 16 (46) | 9 (26) | 9 |
| Dallas, TX | 142 | 116 (82) | 104 (73) | 14 |
| Houston, TX | 77 | 51 (66) | 39 (51) | 8 |
| Los Angeles, CA | 240 | 128 (53) | 102 (43) | 28 |
| Miami, FL | 40 | 17 (43) | 6 (15) | 13 |
| San Diego, CA | 80 | 28 (35) | 16 (20) | 13 |
| San Francisco, CA | 39 | 9 (23) | 5 (13) | 6 |
| St Petersburg, FL | 22 | 5 (23) | 5 (23) | 4 |
Area defined based on US Department of HUD Continuums of Care.18 Areas included in the table have an estimated population of PEH ≥ 10,000 in 2016 and TB incidence greater than the national average of 36 cases per 100,000 PEH during 2011–2016.
Total number of TB cases with Mycobacterium tuberculosis isolate genotyping results (ie, complete data for the plausible source-case method to estimate recent transmission).
Cases are assessed using the plausible source-case method to estimate recent transmission. A given case is considered to have a plausible source if any case can be identified in the national TB molecular surveillance database that 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 before the case’s diagnosis date.
Proportions are calculated using all genotyped cases as the denominators.
For each given case, all plausible source cases identified were further reviewed to determine homelessness status. If any of the plausible source cases also reported homelessness, they were included in these counts.
GENTypes are defined as unique combinations of spacer oligonucleotide typing (spoligotyping) and 24-locus MIRU-VNTR typing results. Occasionally, nominally different GENTypes are shown to be closely related by wgSNP analyses and could be considered part of the same TB cluster or chain of transmission.
HUD indicates Housing and Urban Development; MIRU-VNTR, mycobacterial interspersed repetitive unit-variable number tandem repeat; PEH, persons experiencing homelessness; TB, tuberculosis; wgSNP, whole-genome single nucleotide polymorphism.