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Foreign-born persons in the United States seeking to adjust their status to permanent resident must undergo screening for tuberculosis (TB) disease. Screening is performed by civil surgeons (CS) following technical instructions by the Centers for Disease Control and Prevention. From 2011 to 2012, 1,369 practicing CS in California, Texas, and New England were surveyed to investigate adherence to the instructions. A descriptive analysis was conducted on 907 (66 %) respondents. Of 907 respondents, 739 (83 %) had read the instructions and 565 (63 %) understood that a chest radiograph is required for status adjustors with TB symptoms; however, only 326 (36 %) knew that a chest radiograph is required for immunosuppressed status adjustors. When suspecting TB disease, 105 (12 %) would neither report nor refer status adjustors to the health department; 91 (10 %) would neither start treatment nor refer for TB infection. Most CS followed aspects of the technical instructions; however, educational opportunities are warranted to ensure positive patient outcomes.

Improvements in diagnosis of tuberculosis disease are needed. Sputum-smear microscopy for acid-fast-bacilli (AFB) is simple and inexpensive to perform but generally detects less than half of patients with culture-confirmed pulmonary Mycobacterium tuberculosis complex disease (culture-positivity) [1, 2] and has a poor positive predictive value (PPV) in persons with human immunodeficiency virus (HIV) infection [3, 4]. While culture is the gold standard for active tuberculosis diagnosis, it takes 2–8 weeks for results [1]. Nucleic acid amplification testing for M. tuberculosis can provide information within 24–48 hours. A meta-analysis of M. tuberculosis direct nucleic acid amplification testing (MTD, Gen-Probe, San Diego, California) studies found sensitivity of 97% and specificity of 96% among smear-positive respiratory specimens, and sensitivity of 76% and specificity of 97% among smear-negative specimens [5]. The US Food and Drug Administration (FDA) approved the MTD in 1995 for smear-positive specimens and an enhanced MTD in 1999 for both smear-positive and smear-negative specimens. The Centers for Disease Control and Prevention (CDC) recommended in 1996 and 2000 that nucleic acid amplification testing be performed on at least one (preferably the first) respiratory specimen if smear-positive, and beginning in 2009 on smear-negative specimens from patients for whom the test result would alter tuberculosis case management [6]. Despite these recommendations, the request for MTD by individual providers, hospitals, and laboratories determines its use, which is not universal. Moreover, there are limited US data demonstrating the cost-effectiveness of the MTD, which might influence its use. D. W. Dowdy evaluated the MTD in smear-positive patients having 31.4% tuberculosis prevalence at a US urban hospital and found it not cost-effective for early tuberculosis exclusion in that setting [7]. The purpose of this study is to evaluate the use, effectiveness, health-system benefits, and cost-effectiveness of MTD in a retrospective cohort of patients reported to have suspected pulmonary tuberculosis in 2008–2010 from Georgia, Hawaii, Maryland, and Massachusetts. Study results will help guide future decisions about efficient MTD and provide a baseline for newer molecular tuberculosis disease diagnostics, such as Xpert INH/RIF (Cepheid, Sunnyvale, California).

Summary Objective Low rates of completion of treatment for latent tuberculosis infection (LTBI) limit its usefulness as a strategy for elimination of tuberculosis (TB) in the United States. This retrospective cohort study assessed predictors of completion of LTBI treatment among patients seen at an urban United States TB clinic in 1998. Methods A retrospective cohort study of acceptance and completion of LTBI treatment among patients first seen in a TB clinic in 1998 was performed. Results Of 2621 persons with a positive tuberculosis skin test (TST), 1723 were offered treatment and 1572 (91.2%) accepted. Of the 1572 who accepted, treatment was completed by 607 (38.6%). Of those persons who failed to complete treatment, 517/965 (54%) dropped out before the end of the first month of the course. Among 1375 persons under 35years of age who initiated LTBI treatment, failure to complete was associated with birth in Haiti (OR=2.17, CI 95% 1.49–3.17) or the Dominican Republic (OR=1.93, CI 95% 1.08–3.43). Conclusion These results suggest that country-specific cultural and behavioral factors may contribute to failure to complete LTBI treatment, and that interventions to increase completion should focus on the first month after initiation.

Objectives. We compared mortality among tuberculosis (TB) survivors and a similar population. Methods. We used local health authority records from 3 US sites to identify 3853 persons who completed adequate treatment of TB and 7282 individuals diagnosed with latent TB infection 1993 to 2002. We then retrospectively observed mortality after 6 to 16 years of observation. We ascertained vital status as of December 31, 2008, using the Centers for Disease Control and Prevention’s National Death Index. We analyzed mortality rates, hazards, and associations using Cox regression. Results. We traced 11 135 individuals over 119 772 person-years of observation. We found more all-cause deaths (20.7% vs 3.1%) among posttreatment TB patients than among the comparison group, an adjusted average excess of 7.6 deaths per 1000 person-years (8.8 vs 1.2; P Conclusions. Fully treated TB is still associated with substantial mortality risk. Cure as currently understood may be insufficient protection against TB-associated mortality in the years after treatment, and TB prevention may be a valuable opportunity to modify this risk.

We used molecular genotyping to further understand the epidemiology and transmission patterns of tuberculosis (TB) in Massachusetts. The study population included 983 TB patients whose cases were verified by the Massachusetts Department of Public Health between July 1, 1996, and December 31, 2000, and for whom genotyping results and information on country of origin were available. Two hundred seventy-two (28%) of TB patients were in genetic clusters, and isolates from U.S-born were twice as likely to cluster as those of foreign-born (odds ratio [OR] 2.29, 95% confidence interval [CI] 1.69 to 3.12). Our results suggest that restriction fragment length polymorphism analysis has limited capacity to differentiate TB strains when the isolate contains six or fewer copies of IS6110, even with spoligotyping. Clusters of TB patients with more than six copies of IS6110 were more likely to have epidemiologic connections than were clusters of TB patients with isolates with few copies of IS6110 (OR 8.01, 95%; CI 3.45 to 18.93).

Data collected by health maintenance organizations (HMOs), which provide care for an increasing number of persons with tuberculosis (TB), may be used to complement traditional TB surveillance. We evaluated the ability of HMO-based surveillance to contribute to overall TB reporting through the use of routinely collected automated data for approximately 350,000 HMO members. During approximately 1.5 million person-years, 45 incident cases were identified in either HMO or public health department records. Eight (18%) confirmed cases had not been identified by the public health department. The most useful screening criterion (sensitivity of 89% and predictive value positive of 30%) was dispensing of two or more TB drugs. Pharmacy dispensing information routinely collected by many HMOs appears to be a useful adjunct to traditional TB surveillance, particularly for identifying cases without positive microbiologic results that may be missed by traditional public health surveillance methods.

Increased risk for tuberculosis (TB) disease has been identified in foreign-born persons in the United States, particularly during the first 5 years after their arrival in the United States. This could be explained by undetected TB disease at entry, increased prevalence of latent TB infection (LTBI), increased progression from LTBI to TB, or a combination of these factors.We performed a cluster analysis of TB cases in Boston and a case-control study of risk factors for TB with an unclustered isolate among Boston residents with LTBI to determine whether such persons have an increased risk for reactivation of disease.Of 321 case patients with TB seen between 1996 and 2000, 133 isolates were clustered and 188 were not. In multivariate analysis, foreign birth was associated with an unclustered isolate (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2 to 3.8; p0.01), while being a close contact of a TB case was negatively associated (OR, 0.22; 95% CI, 0.07 to 0.73; p = 0.02). When 188 TB patients with unclustered isolates were compared to 188 age-matched control subjects with LTBI, there was no association between the occurrence of TB and foreign birth (OR, 0.71; 95% CI, 0.42 to 1.3); among foreign-born persons, there was no association between the occurrence of TB and being in the United Statesor= 5 years (OR, 0.90; 95% CI, 0.56 to 1.44).We conclude that the increased risk for TB among foreign-born persons in the United States may be attributable to the increased prevalence of LTBI among foreign-born persons or the increased prevalence of active disease at arrival in the United States, but not to an increased rate of reactivation among persons with LTBI.

Objectives To describe persons with suspected (did not meet the national tuberculosis [TB] surveillance case definition) and noncounted TB (met the TB case definition but transferred and were counted by another jurisdiction) and estimate costs incurred by public health departments for managing them. Methods We reviewed TB registry, medical records, budgets, bills, salaries, organizational charts, and travel/activity logs from the year 2000 at health departments in New York City (NYC), three Texas (TX) counties (El Paso, Hidalgo, and Webb), and Massachusetts (MA). We also interviewed or observed personnel to estimate the time spent on activities for these patients. Results In 2000, NYC and MA had more persons with suspected (n = 2,996) and noncounted (n = 163) TB than with counted (n = 1,595) TB. TX counties had more persons with counted TB (n = 179) than with suspected (n = 55) and noncounted (n = 15) TB. Demographic and clinical characteristics varied widely. For persons with suspected TB, NYC spent an estimated $1.7 million, with an average cost of $636 for each person; TX counties spent $60,928 ($1,108 per patient); and MA spent $1.1 million ($3,330 per patient). For persons with noncounted TB, NYC spent $303,148 ($2,180 per patient), TX counties spent $40,002 ($2,667 per patient), and MA spent $84,603 ($3,525 per patient). Conclusions Health departments incurred substantial costs in managing persons with suspected and noncounted TB. These costs should be considered when allocating TB program resources.

We conducted a population-based study to assess demographic and risk-factor correlates for the most frequently occurring Mycobacterium tuberculosis genotypes from tuberculosis (TB) patients. The study included all incident, culture-positive TB patients from seven sentinel surveillance sites in the United States from 1996 to 2000. M. tuberculosis isolates were genotyped by IS6110-based restriction fragment length polymorphism and spoligotyping. Genotyping was available for 90% of 11,923 TB patients. Overall, 48% of cases had isolates that matched those from another patient, including 64% of U.S.-born and 35% of foreign-born patients. By logistic regression analysis, risk factors for clustering of genotypes were being male, U.S.-born, black, homeless, and infected with HIV; having pulmonary disease with cavitations on chest radiograph and a sputum smear with acid-fast bacilli; and excessive drug or alcohol use. Molecular characterization of TB isolates permitted risk correlates for clusters and specific genotypes to be described and provided information regarding cluster dynamics over time.

Background Tracking the dissemination of specific Mycobacterium tuberculosis (Mtb) strains using genotyped Mtb isolates from tuberculosis patients is a routine public health practice in the United States. The present study proposes a standardized cluster investigation method to identify epidemiologic-linked patients in Mtb genotype clusters. The study also attempts to determine the proportion of epidemiologic-linked patients the proposed method would identify beyond the outcome of the conventional contact investigation. Methods The study population included Mtb culture positive patients from Georgia, Maryland, Massachusetts and Houston, Texas. Mtb isolates were genotyped by CDC’s National TB Genotyping Service (NTGS) from January 2006 to October 2010. Mtb cluster investigations (CLIs) were conducted for patients whose isolates matched exactly by spoligotyping and 12-locus MIRU-VNTR. CLIs were carried out in four sequential steps: (1) Public Health Worker (PHW) Interview, (2) Contact Investigation (CI) Evaluation, (3) Public Health Records Review, and (4) CLI TB Patient Interviews. Comparison between patients whose links were identified through the study’s CLI interviews (Step 4) and patients whose links were identified earlier in CLI (Steps 1–3) was conducted using logistic regression. Results Forty-four clusters were randomly selected from the four study sites (401 patients in total). Epidemiologic links were identified for 189/401 (47 %) study patients in a total of 201 linked patient-pairs. The numbers of linked patients identified in each CLI steps were: Step 1 - 105/401 (26.2 %), Step 2 - 15/388 (3.9 %), Step 3 - 41/281 (14.6 %), and Step 4 - 28/119 (30 %). Among the 189 linked patients, 28 (14.8 %) were not identified in previous CI. No epidemiologic links were identified in 13/44 (30 %) clusters. Conclusions We validated a standardized and practical method to systematically identify epidemiologic links among patients in Mtb genotype clusters, which can be integrated into the TB control and prevention programs in public health settings. The CLI interview identified additional epidemiologic links that were not identified in previous CI. One-third of the clusters showed no epidemiologic links despite being extensively investigated, suggesting that some improvement in the interviewing methods is still needed. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-1937-9) contains supplementary material, which is available to authorized users.