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RATIONALE AND OBJECTIVES: Identifying and treating persons with latent tuberculosis (TB) infection (LTBI) at high risk for developing TB is part of the current TB elimination strategy. There are no specific criteria, other than medical risks, to designate groups as high risk for developing TB. We hypothesized that, if location-based screenings were done in communities where persons with genotypically clustered Mycobacterium tuberculosis resided, then persons with LTBI from recent transmission and with undiagnosed TB could be identified. METHODS: Location-based TB screenings were done in partnership with multiple community-based organizations using resources previously used for other types of screening. MAIN RESULTS: Location-based screenings identified one person with TB for every 83 screened, and one person with LTBI for every five screened. The yield of this targeted screening program for discovering persons with TB and LTBI exceeded what would be expected from nontargeted screening in a county with a TB incidence of 5.7 per 100,000 population. CONCLUSIONS: Genotyping combined with geographic information systems analysis can potentially be used to define high-risk status and to define areas for location-based TB screenings. [ABSTRACT FROM AUTHOR]

Rationale: Diagnosis of latent tuberculosis infection (LTBI) is currently based on the tuberculin skin test. The enzyme-linked immunospot assay (ELISPOT) is a new blood test to diagnose LTBI.Objective: To compare the ELISPOT and the tuberculin skin test for detecting LTBI in contacts of patients with tuberculosis.Methods: Prospective study of 413 contacts of patients with tuberculosis.Measurements and Main Results: Because there is no gold standard for LTBI, the sensitivity and specificity of the ELISPOT and tuberculin skin test cannot be directly measured. For each contact, we therefore estimated the likelihood of having LTBI by calculating a contact score that quantified exposure to and infectiousness of the index case. We analyzed the relationship of contact score to ELISPOT and tuberculin skin test results. The likelihood of a positive ELISPOT (p = 0.0005) and a tuberculin skin test (p = 0.01) increased significantly with rising contact scores. The contact score was more strongly related to the ELISPOT than to the tuberculin skin test results, although this difference was not statistically significant. Among U.S.-born persons and those who were not vaccinated with bacille Calmette-Guérin, approximately 30% had positive ELISPOT or tuberculin skin test results. Foreign-born, bacille Calmette-Guérin-vaccinated persons were significantly more likely to have a positive tuberculin skin test than a positive ELISPOT result (p < 0.0001).Conclusions: Compared with the tuberculin skin test, the ELISPOT appears to be at least as sensitive for diagnosis of LTBI in contacts of patients with tuberculosis. [ABSTRACT FROM AUTHOR]

Rationale: India reports the largest number of multidrug-resistant tuberculosis cases in the world; yet, no longitudinal study has assessed factors related to treatment outcomes under programmatic conditions in the public sector., Objectives: To describe demographic, clinical, and risk characteristics associated with treatment outcomes for all patients with multidrug-resistant tuberculosis registered in the Revised National Tuberculosis Control Programme, Kerala State, India from January 1, 2009 to June 30, 2010., Methods: Cox regression methods were used to calculate adjusted hazard ratios with 95% confidence intervals (CIs) to assess factors associated with an unsuccessful treatment outcome., Measurements and Main Results: Of 179 patients with multidrug-resistant tuberculosis registered, 112 (63%) had successful treatment outcomes (77 bacteriologically cured, 35 treatment completed) and 67 (37%) had unsuccessful treatment outcomes (30 died, 26 defaulted, 9 failed treatment, 1 stopped treatment because of drug-related adverse events, and 1 developed extensively drug-resistant tuberculosis). The hazard for unsuccessful outcome was significantly higher among patients who consumed alcohol during treatment (adjusted hazard ratio, 4.3; 95% CI, 1.1-17.6) than those who did not. Persons who consumed alcohol during treatment, on average, missed 18 more intensive-phase doses (95% CI, 13-22) than those who did not. Although many patients had diabetes (33%), were ever smokers (39%), or had low body mass index (47%), these factors were not associated with outcome., Conclusion: Overall treatment success was greater than global and national averages; however, outcomes among patients consuming alcohol remained poor. Integration of care for multidrug-resistant tuberculosis and alcoholism should be considered to improve treatment adherence and outcomes.

Background: In 2010, Mexico was the most common (22.9%) country of origin for foreign-born persons with tuberculosis in the United States, and overall trends in tuberculosis morbidity are substantially influenced by the Mexico-born population., Objectives: To determine the risk of tuberculosis disease among Mexico-born persons living in the United States., Methods: Using data from the U.S. National Tuberculosis Surveillance System and the American Community Survey, we examined tuberculosis case counts and case rates stratified by years since entry into the United States and geographic proximity to the United States-Mexico border. We calculated trends in case rates over time measured by average annual percent change., Results: The total tuberculosis case count (-14.5%) and annual tuberculosis case rate (average annual percent change -5.1%) declined among Mexico-born persons. Among those diagnosed with tuberculosis less than 1 year since entry into the United States (newly arrived persons), there was a decrease in tuberculosis cases (-60.4%), no change in tuberculosis case rate (average annual percent change of 0.0%), and a decrease in population (-60.7%). Among those living in the United States for more than 5 years (non-recently arrived persons), there was an increase in tuberculosis cases (+3.4%), a decrease in tuberculosis case rate (average annual percent change of -4.9%), and an increase in population (+62.7%). In 2010, 66.7% of Mexico-born cases were among non-recently arrived persons, compared with 51.1% in 2000. Although border states reported the highest proportions (>15%) of tuberculosis cases that were Mexico-born, the highest Mexico-born-specific tuberculosis case rates (>20/100,000 population) were in states in the eastern and southeastern regions of the United States., Conclusions: The decline in tuberculosis morbidity among Mexico-born persons may be attributed to fewer newly arrived persons from Mexico and lower tuberculosis case rates among non-recently arrived Mexico-born persons. The extent of the decline was dampened by an unchanged tuberculosis case rate among newly arrived persons from Mexico and a large increase in the non-recently arrived Mexico-born population. If current trends continue, tuberculosis morbidity among Mexico-born persons will be increasingly driven by those who have been living in the United States for more than 5 years.

The epidemiology of tuberculosis is changing in the United States as a result of immigration, yet the extent to which different classes of immigrants contribute to overall morbidity is unknown. Tuberculosis in nonimmigrant visitors is of particular interest as they are currently exempt from screening requirements. We conducted a prospective survey of all culture-positive tuberculosis patients in Tarrant County, Texas from 1/98 to 12/00. Immigration status of foreign-born patients was classified as permanent residents, undocumented, or nonimmigrant visitors. Of 274 eligible participants, 114 (42%) were foreign-born; of these, 67 (59%) were permanent residents, 28 (25%) were undocumented, and 19 (17%) were nonimmigrant visitors. Among the foreign-born, we observed significant differences by immigration status in multidrug resistance (p = 0.02), human immunodeficiency virus (HIV) infection (p = 0.0007), and hospitalization (p = 0.03 for ever/never, 0.01 for duration). Compared with other immigrants, more nonimmigrant visitors were multi-drug-resistant (16 % versus 11% of undocumented residents and 1% of permanent residents), were HIV-positive (32% versus 0% of undocumented and 5% of permanent residents), were hospitalized (47% versus 36% of undocumented and 19% of permanent residents), and had lengthy hospitalizations (median [midspread] days = 87 [25 to 153] versus 8.5 [4 to 28] for undocumented and 10 [7 to 24 d] for permanent residents). We found nonimmigrant visitors to be an important source of tuberculosis morbidity in Tarrant County. Further studies in other regions of the U.S. are needed to determine if screening and treatment recommendations of persons who spend extended periods in the U.S. should be raised to the standards set for permanent residents.