Leveling of Tuberculosis Incidence - United States, 2013-2015

Sex disparities of the effect of the COVID-19 pandemic on mortality among patients living with tuberculosis in the United States

Background

We aimed to determine the trend of TB-related deaths during the COVID-19 pandemic.

Methods

TB-related mortality data of decedents aged ≥25 years from 2006 to 2021 were analyzed. Excess deaths were estimated by determining the difference between observed and projected mortality rates during the pandemic.

Results

A total of 18,628 TB-related deaths were documented from 2006 to 2021. TB-related age-standardized mortality rates (ASMRs) were 0.51 in 2020 and 0.52 in 2021, corresponding to an excess mortality of 10.22 and 9.19%, respectively. Female patients with TB demonstrated a higher relative increase in mortality (26.33 vs. 2.17% in 2020; 21.48 vs. 3.23% in 2021) when compared to male. Female aged 45-64 years old showed a surge in mortality, with an annual percent change (APC) of -2.2% pre-pandemic to 22.8% (95% CI: -1.7 to 68.7%) during the pandemic, corresponding to excess mortalities of 62.165 and 99.16% in 2020 and 2021, respectively; these excess mortality rates were higher than those observed in the overall female population ages 45-64 years in 2020 (17.53%) and 2021 (33.79%).

Conclusion

The steady decline in TB-related mortality in the United States has been reversed by COVID-19. Female with TB were disproportionately affected by the pandemic.

Tuberculosis in prison: What about after release? The example of French Guiana

INTRODUCTION

Tuberculosis is a major cause of mortality worldwide. Prisoners in Guiana have multiple risk factors. The primary objective of this study was to describe tuberculosis occurring in prison and after release in French Guiana between 2008 and 2020. Secondary objectives were to identify tuberculosis risk factors and determine annual incidences.

METHODS

A retrospective cohort study of tuberculosis cases was carried out at the Guiana prison between 2008 and 2020. Data were collected from prison registers and cross-referenced with the list of tuberculosis notifications in French Guiana.

RESULTS

A total of 36 cases of tuberculosis were studied. Incidence was high, at 263/100,000 per year, higher than elsewhere in France and comparable to that in Brazil. Despite visibly effective screening on entry, with little evidence of intra-prison circulation of tuberculosis, 39% of patients were diagnosed within two years of leaving prison (76% were symptomatic). This could be explained by the high prevalence of latent forms (LTI).

DISCUSSION

Continued screening on entry, in combination with annual radiological and clinical screening, and reinforced follow-up on release seem indicated to improve patient management and the search for possible LTI.

Prevention of Mycobacterium tuberculosis Transmission in Health Care Settings

Patients with tuberculosis (TB) pose a risk to other patients and health care workers, and outbreaks in health care settings occur when appropriate infection control measures are not used. This article discusses strategies to prevent transmission of Mycobacterium tuberculosis within health care settings. All health care facilities should have an operational TB infection control plan that emphasizes the use of a hierarchy of controls (administrative, environmental, and personal respiratory protection). Resources available to clinicians who work in the prevention and investigation of nosocomial transmission of M tuberculosis also are discussed.

Impact of T-Cell Xtend on T-SPOT.TB Assay in High-Risk Individuals after Delayed Blood Sample Processing

T-SPOT.TB (T-SPOT) is an interferon gamma release assay (IGRA) used to detect infection with Mycobacterium tuberculosis based on the number of spot-forming T cells; however, delays in sample processing have been shown to reduce the number of these spots that are detected following laboratory processing. Adding T-Cell Xtend (XT) into blood samples before processing reportedly extends the amount of time allowed between blood collection and processing up to 32 h. In this study, paired blood samples from 306 adolescents and adults at high risk for latent tuberculosis (TB) infection (LTBI) or progression to TB disease were divided into three groups: (i) early processing (∼4.5 h after collection) with and without XT, (ii) delayed processing (∼24 h after collection) with and without XT, and (iii) early processing without XT and delayed processing with XT. The participants' paired samples were processed at a local laboratory and agreement of qualitative and quantitative results was assessed. The addition of XT did not consistently increase or decrease the number of spots. In groups 1, 2, and 3, samples processed with XT had 13% (10/77), 28.0% (30/107), and 24.6% (30/122), respectively, more spots, while 33.8% (26/77), 26.2% (28/107), and 38.5% (47/122) had fewer spots than samples processed without XT. The findings suggest that XT does not reliably mitigate the loss of spot-forming T cells in samples with processing delay.

Incidence, duration and risk factors associated with delayed and missed diagnostic opportunities related to tuberculosis: a population-based longitudinal study

OBJECTIVES

Missed opportunities to diagnose tuberculosis are costly to patients and society. In this study, we (1) estimate the frequency and duration of diagnostic delays among patients with active pulmonary tuberculosis and (2) determine the risk factors for experiencing a diagnostic delay.

DESIGN

A retrospective cohort study of patients with tuberculosis using longitudinal healthcare encounters prior to diagnosis.

SETTING

Commercially insured enrollees from the Commercial Claims and Encounters or Medicare Supplemental IBM Marketscan Research Databases, 2001-2017.

PARTICIPANTS

All patients diagnosed with, and receiving treatment for, pulmonary tuberculosis, enrolled at least 365 days prior to diagnosis.

PRIMARY AND SECONDARY OUTCOME MEASURES

We estimated the number of visits with tuberculosis-related symptoms prior to diagnosis that would be expected to occur in the absence of delays and compared this estimate to the observed pattern. We computed the number of visits representing a delay and used a simulation-based approach to estimate the number of patients experiencing a delay, number of missed opportunities per patient and duration of delays (ie, time between diagnosis and earliest missed opportunity). We also explored risk factors for missed opportunities.

RESULTS

We identified 3371 patients diagnosed and treated for active tuberculosis that could be followed up for 1 year prior to diagnosis. We estimated 77.2% (95% CI 75.6% to 78.7%) of patients experienced at least one missed opportunity; of these patients, an average of 3.89 (95% CI 3.65 to 4.14) visits represented a missed opportunity, and the mean duration of delay was 31.66 days (95% CI 28.51 to 35.11). Risk factors for delays included outpatient or emergency department settings, weekend visits, patient age, influenza season presentation, history of chronic respiratory symptoms and prior fluoroquinolone use.

CONCLUSIONS

Many patients with tuberculosis experience multiple missed diagnostic opportunities prior to diagnosis. Missed opportunities occur most commonly in outpatient settings and numerous patient-specific, environment-specific and setting-specific factors increase risk for delays.

Impact of Effective Global Tuberculosis Control on Health and Economic Outcomes in the United States

Rationale: Most U.S. residents who develop tuberculosis (TB) were born abroad, and U.S. TB incidence is increasingly driven by infection risks in other countries.

Objectives: To estimate the potential impact of effective global TB control on health and economic outcomes in the United States.

Methods: We estimated outcomes using linked mathematical models of TB epidemiology in the United States and migrants’ birth countries. A base-case scenario extrapolated country-specific TB incidence trends. We compared this with scenarios in which countries achieve 90% TB incidence reductions between 2015 and 2035, as targeted by the World Health Organization’s End TB Strategy (“effective global TB control”). We also considered pessimistic scenarios of flat TB incidence trends in individual countries.

Measurements and Main Results: We estimated TB cases, deaths, and costs and the total economic burden of TB in the United States. Compared with the base-case scenario, effective global TB control would avert 40,000 (95% uncertainty interval, 29,000–55,000) TB cases in the United States in 2020–2035. TB incidence rates in 2035 would be 43% (95% uncertainty interval, 34–54%) lower than in the base-case scenario, and 49% (95% uncertainty interval, 44–55%) lower than in 2020. Summed over 2020–2035, this represents 0.8 billion dollars (95% uncertainty interval, 0.6–1.0 billion dollars) in averted healthcare costs and $2.5 billion dollars (95% uncertainty interval, 1.7–3.6 billion dollars) in productivity gains. The total U.S. economic burden of TB (including the value of averted TB deaths) would be 21% (95% uncertainty interval, 16–28%) lower (18 billion dollars [95% uncertainty level, 8–32 billion dollars]).

Conclusions: In addition to producing major health benefits for high-burden countries, strengthened efforts to achieve effective global TB control could produce substantial health and economic benefits for the United States.

Trending Literature in Spinal Tuberculosis: Bibliographic Analysis of Top 250 Cited Articles

BACKGROUND

This bibliographic analysis aims to identify the top 250 cited articles on spinal tuberculosis (TB) and report on their impact on the spinal field.

METHODS

All databases included in the Thomson Reuters Web of Science were searched for publications on spinal TB. The most cited articles published between 1950 and 2019, with the main focus on orthopaedic surgery, were identified using a multistep approach, and a total of 250 articles were included and analyzed for title, year of publication, total citations, citations in 2019, citation density, article age, journal, first author, senior author, geographic origin, and level of evidence.

RESULTS

The number of citations ranged from 31 to 257, with an average of 65.38. Studies were published from 31 different countries and published in 83 different journals. The top 3 countries, India, United States, and China published a total of 57.8% (n = 145) of all articles. Indian and Chinese researchers seem to be the most resourceful, as 17 of the 31 (54.8%) prospective studies were conducted by them. African centers produced only 3.2% (n = 8) of all included articles. Only 3.2% (n = 8) were of Level 1 evidence on the subject. A total of 37.8% (n = 95) were on diagnosis, while 46.6% (n = 117) dealt with surgery, and only 15.1% (n = 38) were about conservative management. Anil K Jain followed by S Rajasekaran were the most published authors on the subject.

CONCLUSIONS

Indian and Chinese researchers dominate evidence in spinal TB. Regions with high disease burden, such as Africa, do not contribute their data to the literature. Though these are the top cited articles in the subject, their level of evidence needs improvement for better impact of their results.

Assessing Complexity Among Patients With Tuberculosis in California, 1993-2016

Background

Although the number of patients with active tuberculosis (TB) has decreased in the last 25 years, anecdotal reports suggest that the complexity of these patients has increased. However, this complexity and its components have never been quantified or defined. We therefore aimed to describe the complexity of patients with active TB in California during 1993–2016.

Methods

We analyzed data on patient comorbidities, clinical features, and demographics from the California Department of Public Health TB Registry. All adult patients who were alive at the time of TB diagnosis in California during 1993–2016 were included in the analyses. Factors deemed by an expert panel to increase complexity (ie, increased resources or expertise requirement for successful management) were analyzed and included the following: age >75 years, HIV infection, multidrug resistance (MDR), and extrapulmonary TB disease. Second, using additional information on other comorbidities available starting in 2010, we performed exploratory factor analysis on 25 variables in order to define the dimensions of complexity.

Results

Among the 67512 patients analyzed, the proportion of patients with extrapulmonary disease, age >75 years, or MDR-TB each increased over the study period (P < .001), while the proportion of patients with HIV decreased. Furthermore, the proportion of patients with at least 1 factor of those increased, rising from 38.8% to 45.3% (P < .001) from 1993 to 2016. Dimensions of complexity identified in the exploratory factor analysis included the following: race/immigration, social features, elderly/institutionalized, advanced TB, comorbidity, and drug resistance risk.

Conclusions

In this first description of complexity in the setting of TB, we found that the complexity of patients with active TB has risen over the last 25 years in California. These findings suggest that despite the overall decline in active TB cases, effective management of more complex patients may require additional attention and resource investment.

Sustainability of a Tuberculosis Screening Program at an Adult Education Center Through Community-Based Participatory Research

The majority of active tuberculosis (TB) cases in the United States occur through reactivation of latent TB infection among foreign-born individuals. While screening of at-risk individuals through community partnerships is recommended, it is not commonly accomplished. A community-academic partnership developed a TB-screening intervention at an adult education center serving a large foreign-born population in Rochester, Minnesota. The intervention was cocreated with grant support by diverse stakeholders through a community-based participatory research partnership. The intervention was sustained beyond the grant interval through adaptation of staffing inputs, a robust partnership with sustained dialogue around TB and operational issues, and adaptation of governance through coownership of the intervention by the adult education center and the public health department. Eight years of data demonstrate that adult education centers may be effective venues for sustaining partnerships to address TB prevention among at-risk communities.

Comparative Modeling of Tuberculosis Epidemiology and Policy Outcomes in California

Rationale: Mathematical modeling is used to understand disease dynamics, forecast trends, and inform public health prioritization. We conducted a comparative analysis of tuberculosis (TB) epidemiology and potential intervention effects in California, using three previously developed epidemiologic models of TB.Objectives: To compare the influence of various modeling methods and assumptions on epidemiologic projections of domestic latent TB infection (LTBI) control interventions in California.Methods: We compared model results between 2005 and 2050 under a base-case scenario representing current TB services and alternative scenarios including: 1) sustained interruption of Mycobacterium tuberculosis (Mtb) transmission, 2) sustained resolution of LTBI and TB prior to entry of new residents, and 3) one-time targeted testing and treatment of LTBI among 25% of non-U.S.-born individuals residing in California.Measurements and Main Results: Model estimates of TB cases and deaths in California were in close agreement over the historical period but diverged for LTBI prevalence and new Mtb infections-outcomes for which definitive data are unavailable. Between 2018 and 2050, models projected average annual declines of 0.58-1.42% in TB cases, without additional interventions. A one-time LTBI testing and treatment intervention among non-U.S.-born residents was projected to produce sustained reductions in TB incidence. Models found prevalent Mtb infection and migration to be more significant drivers of future TB incidence than local transmission.Conclusions: All models projected a stagnation in the decline of TB incidence, highlighting the need for additional interventions including greater access to LTBI diagnosis and treatment for non-U.S.-born individuals. Differences in model results reflect gaps in historical data and uncertainty in the trends of key parameters, demonstrating the need for high-quality, up-to-date data on TB determinants and outcomes.

Diagnostic Tests for Latent Tuberculosis Infection

Diagnosing latent tuberculosis (TB) infection (LTBI) is important globally for TB prevention. LTBI diagnosis requires a positive test for infection and negative evaluation for active disease. Current tests measure an immunologic response and include the tuberculin skin test (TST) and interferon-gamma release assays (IGRAs), T-SPOT.TB and QuantiFERON. The IGRAs are preferred in bacille Calmette-Guérin-vaccinated populations. The TST is still used when cost or logistical advantages over the IGRAs exist. Both TST and IGRAs have low positive predictive values. Tests that differentiate the TB spectrum and better predict future TB risk are needed.

Changes in tuberculosis epidemiology, United States, 1993-2017

BACKGROUND: After 20 years of steady decline, the pace of decline of tuberculosis (TB) incidence in the United States has slowed.METHODS: Trends in TB incidence rates and case counts since 1993 were assessed using national US surveillance data. Patient characteristics reported during 2014-2017 were compared with those for 2010-2013.RESULTS: TB rates and case counts slowed to an annual decline of respectively 2.2% (95%CI -3.4 to -1.0) and 1.5% (95%CI -2.7 to -0.3) since 2012, with decreases among US-born persons and no change among non-US-born persons. Overall, persons with TB diagnosed during 2014-2017 were older, more likely to have combined pulmonary and extra-pulmonary disease than extra-pulmonary disease alone, more likely to be of non-White race, and less likely to have human immunodeficiency virus infection, or cavitary pulmonary disease. During 2014-2017, non-US-born persons with TB were more likely to have diabetes mellitus, while the US-born were more likely to have smear-positive TB and use non-injecting drugs.CONCLUSION: Changes in epidemiologic trends are likely to affect TB incidence in the coming decades. The Centers for Disease Control and Prevention has called for increased attention to TB prevention through the detection and treatment of latent tuberculous infection.

Understanding the intersection of race and place: the case of tuberculosis in Michigan

BACKGROUND

Race and place intersect to produce location-based variation in disease distributions. We analyzed the geographic distribution of tuberculosis (TB) incidence in Michigan, USA to better understand the complex interplay between race and place, comparing patterns in Detroit, Wayne County and the state of Michigan as a whole.

METHODS

Using cross-sectional TB surveillance data from the Michigan Department of Health and Human Services, multivariable statistical models were developed to analyze the residence patterns of TB incidence from 2007 through 2012. Two-way interactions among the residence location and race of cases were assessed.

RESULTS

Overall, Detroit residents experienced 58% greater TB incidence than residents of Wayne County or the state of Michigan. Racial inequalities were less pronounced in Detroit compared to both Wayne County and the state of Michigan. Blacks in Detroit had 2.01 times greater TB incidence than Whites, while this inequality was 3.62 times more in Wayne County and 8.72 greater in the state of Michigan.

CONCLUSION

Our results highlight how race and place interact to influence patterns of TB disease, and the ways in which this interaction is context dependent. TB elimination in the U.S. will require strategies that address the local social environment, as much as the physical environment.

Tuberculosis Prevention in the Private Sector: Using Claims-Based Methods to Identify and Evaluate Latent Tuberculosis Infection Treatment With Isoniazid Among the Commercially Insured

CONTEXT

Targeted identification and treatment of people with latent tuberculosis infection (LTBI) are key components of the US tuberculosis elimination strategy. Because of recent policy changes, some LTBI treatment may shift from public health departments to the private sector.

OBJECTIVES

To (1) develop methodology to estimate initiation and completion of treatment with isoniazid for LTBI using claims data, and (2) estimate treatment completion rates for isoniazid regimens from commercial insurance claims.

METHODS

Medical and pharmacy claims data representing insurance-paid services rendered and prescriptions filled between January 2011 and March 2015 were analyzed.

PARTICIPANTS

Four million commercially insured individuals 0 to 64 years of age.

MAIN OUTCOME MEASURES

Six-month and 9-month treatment completion rates for isoniazid LTBI regimens.

RESULTS

There was an annual isoniazid LTBI treatment initiation rate of 12.5/100 000 insured persons. Of 1074 unique courses of treatment with isoniazid for which treatment completion could be assessed, almost half (46.3%; confidence interval, 43.3-49.3) completed 6 or more months of therapy. Of those, approximately half (48.9%; confidence interval, 44.5-53.3) completed 9 months or more.

CONCLUSIONS

Claims data can be used to identify and evaluate LTBI treatment with isoniazid occurring in the commercial sector. Completion rates were in the range of those found in public health settings. These findings suggest that the commercial sector may be a valuable adjunct to more traditional venues for tuberculosis prevention. In addition, these newly developed claims-based methods offer a means to gain important insights and open new avenues to monitor, evaluate, and coordinate tuberculosis prevention.

Contextualizing tuberculosis risk in time and space: comparing time-restricted genotypic case clusters and geospatial clusters to evaluate the relative contribution of recent transmission to incidence of TB using nine years of case data from Michigan, USA

PURPOSE

Novel approaches must address the underlying factors sustaining the tuberculosis (TB) epidemic in the United States, specifically what maintains new Mycobacterium tuberculosis (Mtb) transmission.

METHODS

Culture-confirmed TB cases reported to the Michigan Department of Health and Human Services (2004-2012) were analyzed for time-restricted genotypic and/or geospatial clustering. Cases with both types of clustering were used as a proxy for recent, local transmission. Modified, multivariate Poisson regression models were fit to estimate this prevalence in relation to various individual- and neighborhood-level demographic and socio-economic variables.

RESULTS

Those individuals that were spatially clustered were 1.7 times as likely to also be time-restricted genotypically clustered. The prevalence of recent, local transmission was higher among U.S.-born cases, males, and non-Hispanic blacks. Moreover, people living in neighborhoods in the highest poverty quartile had 13.8 times the prevalence of recent, local transmission compared with those in the lowest poverty neighborhoods.

CONCLUSIONS

Our results suggest geographic areas with high concentration of TB cases are likely driven by ongoing transmission, rather than enclaves of individuals who have reactivated a case of latent TB. Furthermore, efforts to continue reducing Mtb transmission in the United States, and other low-incidence settings, must better identify community-level sources of risk, manifested through the complex social interactions among people and their environments.

Whole-genome sequencing-based epidemiological analysis of anti-tuberculosis drug resistance genes in Japan in 2007: Application of the Genome Research for Asian Tuberculosis (GReAT) database

We investigated the lineages of Mycobacterium tuberculosis (Mtb) isolates from the RYOKEN study in Japan in 2007 and the usefulness of genotypic drug susceptibility testing (DST) using the Genome Research for Asian Tuberculosis (GReAT) database. In total, 667 isolates were classified into lineage 1 (4.6%), lineage 2 (0.8%), lineage 2/Beijing (72.1%), lineage 3 (0.5%), and lineage 4 (22.0%). The nationality, gender, and age groups associated with the isolates assigned to lineage 1 were significantly different from those associated with other lineages. In particular, isolates of lineage 1.2.1 (EAI2) formed sub-clusters and included a 2,316-bp deletion in the genome. The proportion of the isolates resistant to at least one anti-tuberculosis (TB) drug was 10.8%, as determined by either the genotypic or phenotypic method of DST. However, the sensitivities to isoniazid, streptomycin, and ethambutol determined by the genotypic method were low. Thus, unidentified mutations in the genome responsible for drug resistance were explored, revealing previously unreported mutations in the katG, gid, and embB genes. This is the first nationwide report of whole-genome analysis of TB in Japan.

Impact and Effectiveness of State-Level Tuberculosis Interventions in California, Florida, New York, and Texas: A Model-Based Analysis

The incidence of tuberculosis (TB) in the United States has stabilized, and additional interventions are needed to make progress toward TB elimination. However, the impact of such interventions depends on local demography and the heterogeneity of populations at risk. Using state-level individual-based TB transmission models calibrated to California, Florida, New York, and Texas, we modeled 2 TB interventions: 1) increased targeted testing and treatment (TTT) of high-risk populations, including people who are non-US-born, diabetic, human immunodeficiency virus (HIV)-positive, homeless, or incarcerated; and 2) enhanced contact investigation (ECI) for contacts of TB patients, including higher completion of preventive therapy. For each intervention, we projected reductions in active TB incidence over 10 years (2016-2026) and numbers needed to screen and treat in order to avert 1 case. We estimated that TTT delivered to half of the non-US-born adult population could lower TB incidence by 19.8%-26.7% over a 10-year period. TTT delivered to smaller populations with higher TB risk (e.g., HIV-positive persons, homeless persons) and ECI were generally more efficient but had less overall impact on incidence. TTT targeted to smaller, highest-risk populations and ECI can be highly efficient; however, major reductions in incidence will only be achieved by also targeting larger, moderate-risk populations. Ultimately, to eliminate TB in the United States, a combination of these approaches will be necessary.

Increasing likelihood of advanced pulmonary tuberculosis at initial diagnosis in a low-incidence US state

SETTING

Arkansas, USA.

OBJECTIVE

To investigate the relationship between an increase in the proportion of cases with advanced disease at first diagnosis and the recently observed slowing of the decline in tuberculosis (TB) incidence in low-incidence US states.

DESIGN

We conducted descriptive statistical analyses of de-identified surveillance data of 1246 culture-confirmed TB patients reported in Arkansas during 1996-2013. We then fitted stepwise, multivariate logistic regression models to identify predictors for advanced disease at diagnosis, defined as having either smear-positive sputum or lung cavitation.

RESULTS

From 1996 to 2013, the proportion of new cases with positive sputum smear and cases with lung cavitation increased from 51.6% to 75% and from 37.7% to 50%, respectively. Patients diagnosed during 2006-2013 were more likely to have positive sputum smears (adjusted odds ratio [aOR] 2.55, 95%CI 1.95-3.35) or lung cavitation (aOR 1.49, 95%CI 1.14-1.95) than those diagnosed during 1996-2005. During 1996-2013, age 15-64 years and excessive alcohol use were predictive of positive sputum smear or lung cavitation.

CONCLUSION

Measures to reduce the proportion of cases with advanced disease at first diagnosis may be helpful to achieve further decline in TB incidence in low-incidence settings.

Tuberculosis Treatment Monitoring by Video Directly Observed Therapy in 5 Health Districts, California, USA

We assessed video directly observed therapy (VDOT) for monitoring tuberculosis treatment in 5 health districts in California, USA, to compare adherence between 174 patients using VDOT and 159 patients using in-person directly observed therapy (DOT). Multivariable linear regression analyses identified participant-reported sociodemographics, risk behaviors, and treatment experience associated with adherence. Median participant age was 44 (range 18–87) years; 61% of participants were male. Median fraction of expected doses observed (FEDO) among VDOT participants was higher (93.0% [interquartile range (IQR) 83.4%–97.1%]) than among patients receiving DOT (66.4% [IQR 55.1%–89.3%]). Most participants (96%) would recommend VDOT to others; 90% preferred VDOT over DOT. Lower FEDO was independently associated with US or Mexico birth, shorter VDOT duration, finding VDOT difficult, frequently taking medications while away from home, and having video-recording problems (p<0.05). VDOT cost 32% (range 6%–46%) less than DOT. VDOT was feasible, acceptable, and achieved high adherence at lower cost than DOT.

Outlook for tuberculosis elimination in California: An individual-based stochastic model

Rationale

As part of the End TB Strategy, the World Health Organization calls for low-tuberculosis (TB) incidence settings to achieve pre-elimination (<10 cases per million) and elimination (<1 case per million) by 2035 and 2050, respectively. These targets require testing and treatment for latent tuberculosis infection (LTBI).

Objectives

To estimate the ability and costs of testing and treatment for LTBI to reach pre-elimination and elimination targets in California.

Methods

We created an individual-based epidemic model of TB, calibrated to historical cases. We evaluated the effects of increased testing (QuantiFERON-TB Gold) and treatment (three months of isoniazid and rifapentine). We analyzed four test and treat targeting strategies: (1) individuals with medical risk factors (MRF), (2) non-USB, (3) both non-USB and MRF, and (4) all Californians. For each strategy, we estimated the effects of increasing test and treat by a factor of 2, 4, or 10 from the base case. We estimated the number of TB cases occurring and prevented, and net and incremental costs from 2017 to 2065 in 2015 U.S. dollars. Efficacy, costs, adverse events, and treatment dropout were estimated from published data. We estimated the cost per case averted and per quality-adjusted life year (QALY) gained.

Measurements and main results

In the base case, 106,000 TB cases are predicted to 2065. Pre-elimination was achieved by 2065 in three scenarios: a 10-fold increase in the non-USB and persons with MRF (by 2052), and 4- or 10-fold increase in all Californians (by 2058 and 2035, respectively). TB elimination was not achieved by any intervention scenario. The most aggressive strategy, 10-fold in all Californians, achieved a case rate of 8 (95% UI 4–16) per million by 2050. Of scenarios that reached pre-elimination, the incremental net cost was $20 billion (non-USB and MRF) to $48 billion. These had an incremental cost per QALY of $657,000 to $3.1 million. A more efficient but somewhat less effective single-lifetime test strategy reached as low as $80,000 per QALY.

Conclusions

Substantial gains can be made in TB control in coming years by scaling-up current testing and treatment in non-USB and those with medical risks.

Tuberculosis Surveillance and Control, Puerto Rico, 1898-2015

The World Health Organization recognizes Puerto Rico as an area of low tuberculosis (TB) incidence, where TB elimination is possible by 2035. To describe the current low incidence of reported cases, provide key lessons learned, and detect areas that may affect progress, we systematically reviewed the literature about the history of TB surveillance and control in Puerto Rico and supplemented this information with additional references and epidemiologic data. We reviewed 3 periods: 1898-1946 (public health efforts before the advent of TB chemotherapy); 1947-1992 (control and surveillance after the introduction of TB chemotherapy); and 1993-2015 (expanded TB control and surveillance). Although sustained surveillance, continued care, and use of newly developed strategies occurred concomitantly with decreased incidence of reported TB cases and mortality rates, factors that may affect progress remain poorly understood and include potential delayed diagnosis and underreporting, the effects of government debt and Hurricane Maria, and poverty.

A scoring strategy for progression risk and rates of treatment completion in subjects with latent tuberculosis

It is unknown whether patients with LTBI at high vs. low risk of developing active TB are currently adequately identified and treated in the US. In this study our objective was 1) To retrospectively apply the online calculator (tstin3d.com) to determine the probability of having LTBI and assign cumulative risk of progression. 2) Measure treatment outcomes in subjects with Low: 0-<10%, Intermediate: 10-<50% and High: 50–100% cumulative risk. We performed medical record review of tuberculin skin test and/or Interferon-γ release assay (IGRAs) positive patients with LTBI seen from 2010–2015. Of 125 subjects included, 51(41%), 46 (37%) and 28 (22%) subjects were in Low, Intermediate and High risk groups respectively. Tstin3d.com was useful in determining the probability of LTBI in tuberculin skin test positive US-born subjects. Overall treatment completion rate was 61% in 114 subjects with complete treatment information and similar completion rates were seen in the three groups (Low-60%, Intermediate-63% and High-57%). Provider assessment of important clinical risk factors was often incomplete. Logistic regression analysis showed no association of assessment of important risk factors with treatment completion. The major limitations of the calculator are the lack of an updated data on country-specific prevalence of TB disease as the global burden of TB continues to decrease as well as falsely high positive predictive values that due to “transiently” positive IGRA results in subjects from countries with low prevalence. Nonetheless, our findings suggest that tstin3d.com could be utilized in the US setting for improving providing awareness of risk stratification of patients with LTBI for short course treatment regimens based on risk.

Latent Tuberculosis and Current Health Disparities in California: Making the Invisible Visible

Tuberculosis (TB) continues to have devastating consequences for patients both globally and locally, with disease risk concentrated in specific subgroups defined by race, ethnicity, and nativity. We highlight TB disparities in California in 2016, and describe opportunities to reduce disparities by scaling up screening and treatment of latent TB infection (LTBI) in primary care settings. Primary impediments to mainstreaming LTBI screening and treatment and reducing TB disparities include poor understanding of patient-level barriers, knowledge gaps on the part of health care providers, and insufficient promotion of effective testing and treatment strategies. To overcome these barriers, efforts should focus on finding and engaging high-risk patients and the providers who serve them, as well as enabling health care systems to adopt recommended strategies for testing and treatment through improved dissemination of policy, tracking and measuring LTBI outcomes, and reducing financial barriers to LTBI treatment.

Contemporary Social Disparities in TB Infection and Disease in the USA: a Review

PURPOSE OF REVIEW

Socioeconomic status (SES) has long been understood to be a key determinant of the distribution of tuberculosis (TB), and the role of social factors has long been a truism of TB epidemiology. We review studies that have examined the social determinants of TB in the USA in the past 20 years. We pay particular attention to how the findings of these studies fit within the framework of fundamental cause theory and argue that a more explicit linkage with fundamental cause theory is critical for understanding the current state of TB health disparities in the USA and for charting a way towards TB elimination in the USA.

RECENT FINDINGS AND SUMMARY

Our review finds that while in the past 20 years there have been studies that have documented the ongoing association between social factors and TB disease in the USA, few studies explore the precise mechanisms through which social factors continue to influence TB patterns. We advocate for a move towards a system-based approach both in theory development and analyses, allowing for the incorporation of more complex social dynamics to address long-standing disparities in TB disease.

Prospects for Tuberculosis Elimination in the United States: Results of a Transmission Dynamic Model

We estimated long-term tuberculosis (TB) trends in the US population and assessed prospects for TB elimination. We used a detailed simulation model allowing for changes in TB transmission, immigration, and other TB risk determinants. Five hypothetical scenarios were evaluated from 2017 to 2100: 1) maintain current TB prevention and treatment activities (base case); 2) provision of latent TB infection testing and treatment for new legal immigrants; 3) increased uptake of latent TB infection screening and treatment among high-risk populations, including a 3-month isoniazid-rifapentine regimen; 4) improved TB case detection; and 5) improved TB treatment quality. Under the base case, we estimate that by 2050, TB incidence will decline to 14 cases per million, a 52% (95% posterior interval (PI): 35, 67) reduction from 2016, and 82% (95% posterior interval: 78, 86) of incident TB will be among persons born outside of the United States. Intensified TB control could reduce incidence by 77% (95% posterior interval: 66, 85) by 2050. We predict TB may be eliminated in US-born but not non-US-born persons by 2100. Results were sensitive to numbers of people entering the United States with latent or active TB, and were robust to alternative interpretations of epidemiologic evidence. TB elimination in the United States remains a distant goal; however, strengthening TB prevention and treatment could produce important health benefits.

Diagnosis of Tuberculosis in an Asymptomatic Child, Sibling, and Symptomatic Pregnant Mother in New York City by Tuberculin Skin Testing and the Importance of Screening High-Risk Urban Populations for Tuberculosis

BACKGROUND In 2017, in New York City (NYC), 86% of the cases of tuberculosis (TB) occurred in patients who were born outside the United States (US). This case report illustrates the importance of the use of the tuberculin skin test (TST), and other tests for TB infection (TTBI), in screening high-risk groups, the challenges of diagnosing TB in young children, and highlights the importance of preventing a delay in the diagnosis of TB in family members. CASE REPORT Following a routine TST in an asymptomatic 10-year-old girl, a diagnosis of TB was made, which was confirmed on chest X-ray (CXR) and by the presence of acid-fast bacilli (AFB) in the sputum. Her family had emigrated from China to NYC ten years previously. All the family was screened using the TST, which was positive in her 2-year-old sister and her 37-year-old pregnant mother, and pulmonary TB was confirmed on CXR and by AFBs in the sputum. All three family members and the newborn baby were treated according to current guidelines, with a good clinical outcome. CONCLUSIONS This case report raises awareness about the lack of symptoms in childhood TB and the importance of screening high-risk patients in an urban immigrant population. In children under 5 years of age, a diagnosis of TB can indicate a sentinel event, suggesting a potential undiagnosed or untreated source case, which is usually an adult family member. This report highlights the challenges of diagnosing TB in children, who may be asymptomatic with negative laboratory findings.

Isoniazid-Rifapentine for Latent Tuberculosis Infection: A Systematic Review and Meta-analysis

CONTEXT

Latent tuberculosis infection diagnosis and treatment is a strategic priority for eliminating tuberculosis in the U.S. The Centers for Disease Control and Prevention has recommended the short-course regimen of 3-month isoniazid-rifapentine administered by directly observed therapy. However, longer-duration regimens remain the most widely prescribed latent tuberculosis infection treatments. Limitation on adoption of 3-month isoniazid-rifapentine in the U.S. might be because of patients' preference for self-administered therapy, providers' lack of familiarity with 3-month isoniazid-rifapentine, or lack of resources to support directly observed therapy. This review examines the most recent evidence regarding 3-month isoniazid-rifapentine's effectiveness, safety, and treatment completion when directly compared with other latent tuberculosis infection regimens primarily comprising 9-month isoniazid treatment.

EVIDENCE ACQUISITION

Using Community Guide methodology, reviewers identified, evaluated, and summarized available evidence published during January 2006-June 2017. Analysis of the data was completed in 2017.

EVIDENCE SYNTHESIS

The analysis included 15 unique studies. Three-month isoniazid-rifapentine was determined to be equal to other latent tuberculosis infection regimens in effectiveness (OR=0.89, 95% CI=0.46, 1.70), and has higher treatment completion (87.5%, 95% CI=83.2%, 91.3%) compared with other latent tuberculosis infection regimens (65.9%, 95% CI=53.5%, 77.3%). Three-month isoniazid-rifapentine was associated with similar risk to other latent tuberculosis infection regimens for adverse events (relative risk=0.59, 95% CI=0.23, 1.52); discontinuing treatment because of adverse events (relative risk=0.48, 95% CI=0.17, 1.34); and death (relative risk=0.79, 95% CI=0.56, 1.11).

CONCLUSIONS

The 3-month isoniazid-rifapentine regimen is as safe and effective as other recommended latent tuberculosis infection regimens and achieves significantly higher treatment completion rates.

Risk Factors for Indeterminate Outcome on Interferon Gamma Release Assay in Non-US-Born Persons Screened for Latent Tuberculosis Infection

Background

Non-US-born individuals account for the majority of active tuberculosis (TB) in the United States. Interferon gamma release assay (IGRA) is the preferred diagnostic test for latent TB but can produce an indeterminate result. We investigated the prevalence and predictors of an indeterminate IGRA (IND-IGRA) in a diverse cohort of non-US-born individuals and evaluated outcomes after IND-IGRA.

Methods

We identified patient age ≥18 years who had an outpatient IGRA between 2010 and 2017 in our health system and whose primary language was not English. We used univariate and multivariable logistic regression to examine the association of IND-IGRA with a variety of clinical factors.

Results

Of 3128 outpatients with ≥1 IGRA done, 33% were Asian, 30% Hispanic, and 29% black; 44% were men, and the median age was 50 years. An initial IND-IGRA occurred in 118 (3.8%; 95% confidence interval [CI], 3.1%–4.5%); notably, Asian race (55%) and rheumatologic conditions (25%) were prevalent in this group. In multivariable analysis, Asian race was independently associated with IND-IGRA (adjusted odds ratio [aOR], 2.9; 95% CI, 1.9–4.3), in addition to the presence of anemia and hypoalbuminemia (aOR for interaction, 4.3; 95% CI, 1.3–14.3). Only 55% of patients with an initial IND-IGRA underwent repeat testing; of those who did, 66% had a determinate result.

Conclusions

Asian race and anemia/hypoalbuminemia were independent risk factors for an indeterminate IGRA outcome in foreign-born patients screened in the United States. Our study underscores the importance of following through on indeterminate results in these key subgroups.

Internal Medicine Residents' Knowledge and Practice of Pulmonary Tuberculosis Diagnosis

Background

Internal medicine physicians are often the first providers to encounter patients with a new diagnosis of tuberculosis. Given the public health risks of missed tuberculosis cases, assessing internal medicine residents’ ability to diagnose tuberculosis is important.

Methods

Internal medicine resident knowledge and practice patterns in pulmonary tuberculosis diagnosis at 7 academic hospitals were assessed utilizing (a) a 10-item validated pulmonary tuberculosis diagnosis assessment tool and (b) a retrospective chart review of 343 patients who underwent a pulmonary tuberculosis evaluation while admitted to a resident-staffed internal medicine or infectious disease service. Our primary outcomes were the mean score and percentage of correct responses per assessment tool question, and the percentage of patients who had Centers for Disease Control and Prevention–recommended tuberculosis diagnostic tests obtained.

Results

Of the 886 residents who received the assessment, 541 responded, yielding a response rate of 61%. The mean score on the assessment tool (SD) was 4.4 (1.6), and the correct response rate was 57% (311/541) or less on 9 of 10 questions. On chart review, each recommended test was obtained for ≤43% (148/343) of patients, other than chest x-ray (328/343; 96%). A nucleic acid amplification test was obtained for 18% (62/343) of patients, whereas 24% (83/343) had only 1 respiratory sample obtained. Twenty patients were diagnosed with tuberculosis.

Conclusions

Significant knowledge and practice gaps exist in internal medicine residents’ abilities to diagnose tuberculosis. As residents represent the future providers who will be evaluating patients with possible tuberculosis, such deficiencies must be addressed.

Screening for Latent Tuberculosis Infection Among HIV-Infected Medicaid Enrollees

OBJECTIVES

In the United States, universal screening for latent tuberculosis (TB) infection among people with HIV is recommended, but the percentage receiving screening is unknown. This study assessed screening for latent TB infection among people with HIV enrolled in Medicaid during 2006-2010.

METHODS

We used nationwide fee-for-service Medicaid records to identify people with HIV, measure screening for latent TB infection, and examine associated demographic, social, and clinical factors. We used logistic regression analysis to calculate odds ratios (ORs) and 95% confidence intervals (CIs). We created 2 multivariate models to prevent collinearity between variables for length of HIV infection.

RESULTS

Of 152 831 people with HIV, 26 239 (17.2%) were screened for latent TB infection. The factor most strongly associated with screening was TB exposure or suspected TB (OR = 3.78; 95% CI, 3.27-4.37). Significant demographic characteristics associated with screening included being African American (OR = 1.28; 95% CI, 1.24-1.32) or ≤20 years of age (OR = 1.35; 95% CI, 1.28-1.42). Significant clinical and social factors associated with screening included poor housing conditions, low body mass index, chemotherapy treatment, and use of certain substances (ORs ranged from 1.24 [95% CI, 1.20-1.27] to 1.47 [95% CI, 1.22-1.76]). The screening rate for latent TB infection was higher among people with newly diagnosed HIV infection than among those with established infection (OR = 1.37; 95% CI, 1.32-1.41) and among people with a longer established HIV infection than among those with shorter HIV infection (OR = 1.24; 95% CI, 1.23-1.26 for each additional year).

CONCLUSION

Screening for latent TB infection among fee-for-service Medicaid beneficiaries with HIV was suboptimal, despite the presence of demographic, social, or clinical characteristics that should have increased the likelihood of screening. The lack of certain data in Medicaid may have resulted in an underestimation of screening.

Hospital length of stay and cost burden of HIV, tuberculosis, and HIV-tuberculosis coinfection among pregnant women in the United States

BACKGROUND

We sought to determine hospital length of stay (LOS) and cost burden associated with hospital admissions among pregnant women with HIV monoinfection, tuberculosis (TB) monoinfection, or HIV-TB coinfection in the United States.

METHODS

Analysis covered the period from 2002-2014 using data from the Nationwide Inpatient Sample. Relevant ICD-9-CM codes were used to determine HIV and TB status. Costs associated with hospitalization were calculated and adjusted to 2010 dollars using the medical care component of the Consumer Price Index.

RESULTS

We found modest annual average reduction in HIV, TB, and HIV-TB coinfection rates over the study period. The mean LOS was lowest among mothers free of HIV or TB disease and highest among those with HIV-TB coinfection. The average LOS among mothers diagnosed with TB monoinfection was 60% higher than for those with HIV monoinfection. The cost associated with pregnancy-related hospital admissions among mothers with HIV was approximately 30% higher than disease-free mothers, and the cost more than doubled among patients with TB monoinfection or HIV-TB coinfection.

CONCLUSIONS

TB significantly increased hospital care cost among HIV-positive and HIV-negative pregnant women.

T-SPOT.TB Performance in Routine Pediatric Practice in a Low TB Burden Setting

BACKGROUND

The T-SPOT.TB, an interferon-gamma release assay, is an indirect test of Mycobacterium tuberculosis infection. Due to sparse and conflicting evidence, the use of interferon-gamma release assay is limited in young and HIV-infected children. We determined the prevalence of invalid, borderline, positive and negative results and associations with key demographic variables during routine pediatric use in a low tuberculosis burden setting.

METHODS

For pediatric samples received at Oxford Diagnostic Laboratories between 2010 and 2015, the associations between initial test outcome and demographics were estimated by bivariate analysis and logistic regression.

RESULTS

A total of 44,289 samples (median age 12.5 years; interquartile range 7.7-15.5), including 5057 samples (11.6%) from children under 5 years old, were received from 46 U.S. states, Washington, DC and Puerto Rico. A total of 592 samples (1.3%) could not be tested. T-SPOT.TB positivity was strongly correlated (r = 0.60; P < 0.0001) with state TB incidence. Compared with negative results, positive results were more likely in samples from older children (P < 0.0001), public health clinics (P < 0.0001) and rural locations (P = 0.005). Although infrequent (0.6%), invalid results were more common in samples collected at HIV clinics (odds ratio = 2.5, 95% confidence interval: 1.3-4.9) and from younger children (P = 0.03). These invalid results were more likely due to a robust nil (negative) control response rather than a weak mitogen (positive) control response.

CONCLUSIONS

The T-SPOT.TB test correlated strongly with well-recognized risk factors for tuberculosis infection and provided evaluable results in 98% of children. To optimize the impact of testing on clinical decision making and patient outcomes, local epidemiology and individual patient risk should be considered when incorporating IGRAs into pediatric guidelines.

Private sector tuberculosis prevention in the US: Characteristics associated with interferon-gamma release assay or tuberculin skin testing

OBJECTIVE

To determine whether latent tuberculosis infection risk factors are associated with an increased likelihood of latent tuberculosis infection testing in the US private healthcare sector.

DATA SOURCE

A national sample of medical and pharmacy claims representing services rendered January 2011 through December 2013 for 3,997,986 commercially insured individuals in the US who were 0 to 64 years of age.

STUDY DESIGN

We used multivariable logistic regression models to determine whether TB/LTBI risk factors were associated with an increased likelihood of Interferon-Gamma Release Assay (IGRA) or Tuberculin Skin Test (TST) testing in the private sector.

PRINCIPAL FINDINGS

4.31% (4.27-4.34%) received at least one TST/IGRA test between 2011 and 2013 while 1.69% (1.67-1.72%) received a TST/IGRA test in 2013. Clinical risk factors associated with a significantly increased likelihood of testing included HIV, immunosuppressive therapy, exposure to tuberculosis, a history of tuberculosis, diabetes, tobacco use, end stage renal disease, and alcohol use disorder. Other significant variables included gender, age, asthma, the state tuberculosis rate, population density, and percent of foreign-born persons in a county.

CONCLUSIONS

Private sector TST/IGRA testing is not uncommon and testing varies with clinical risk indicators. Thus, the private sector can be a powerful resource in the fight against tuberculosis. Analyses of administrative data can inform how best to leverage private sector healthcare toward tuberculosis prevention activities.

Tuberculosis during pregnancy in the United States: Racial/ethnic disparities in pregnancy complications and in-hospital death

Background

Despite decades of efforts to eliminate tuberculosis (TB) in the United States (US), TB still contributes to adverse ill health, especially among racial/ethnic minorities. According to the Centers for Disease Control and Prevention, in 2016, about 87% of the TB cases reported in the US were among racial and ethnic minorities. The objective of this study is to explore the risks for pregnancy complications and in-hospital death among mothers diagnosed with TB across racial/ethnic groups in the US.

Methods

This retrospective cohort study utilized National Inpatient Sample data for all inpatient hospital discharges in the US. We analyzed pregnancy-related hospitalizations and births in the US from January 1, 2002 through December 31, 2014 (n = 57,393,459). Multivariable logistic regression was applied to generate odds ratios for the association between TB status and the primary study outcomes (i.e., pregnancy complications and in-hospital death) across racial/ethnic categories.

Results

The prevalence of TB was 7.1 per 100,000 pregnancy-related hospitalizations. The overall prevalence of pregnancy complications was 80% greater among TB-infected mothers than their uninfected counterparts. Severe pre-eclampsia, eclampsia, placenta previa, post-partum hemorrhage, sepsis and anemia occurred with greater frequency among mothers with a TB diagnosis than those without TB, irrespective of race/ethnicity. The rate of in-hospital death among TB patients was 37 times greater among TB-infected than in non-TB infected mothers (468.8 per 100,000 versus 12.6 per 100,000). A 3-fold increased risk of in-hospital death was observed among black TB-negative mothers compared to their white counterparts. No racial/ethnic disparities in maternal morbidity or in-hospital death were found among mothers with TB disease.

Conclusion

TB continues to be an important cause of morbidity and mortality among pregnant women in the US. Resources to address TB disease should also target pregnant women, especially racial/ethnic minorities who bear the greatest burden of the disease.

Understanding tuberculosis in an era of global travel

With the resurgence of tuberculosis (TB), it is imperative that healthcare providers have the necessary skills to manage the specialized issues of prevention, recognition, and treatment of TB. The case study in this article illustrates these skills for NPs and other advanced practice providers.

Most Influential Literature in Spinal Tuberculosis: A Global Disease Without Global Evidence

STUDY DESIGN

Bibliometric review of the literature.

OBJECTIVE

This bibliometric analysis aims to give an overview of the most influential academic literature written on spinal tuberculosis.

METHODS

All databases included in the Thomson Reuters Web of Knowledge were searched for the most influential publications in spinal tuberculosis. The most cited articles published between 1950 and 2015, with the main focus on orthopedic surgery, were identified using a multistep approach, and a total of 100 articles were included. The publications were then analyzed in this bibliometric analysis.

RESULTS

The number of citations ranged from 243 to 36, with an average of 77.11. The articles were published in 34 different journals, and the studies were conducted in 20 different countries. The top 3 countries, India, the United States, and China, published a total of 51% (n = 51) of all articles. Low-burden countries produced 60% (n = 60) of all articles in our list. African centers produced only 4% (n = 4) of all included articles.

CONCLUSIONS

Indian and Chinese researchers dominate evidence in spinal tuberculosis. Other areas with high disease burden, such as Africa, do not feature. Most publications are retrospective studies with a low level of evidence.

Spatial clusters of latent tuberculous infection, Connecticut, 2010-2014

SETTING

In the United States, tuberculosis (TB) control is increasingly focusing on the identification of persons with latent tuberculous infection (LTBI).

OBJECTIVE

To characterize the local epidemiology of LTBI in Connecticut, USA.

METHODS

We used spatial analyses 1) to identify census tract-level clusters of reported LTBI and TB disease in Connecticut, 2) to compare persons and populations in clusters with those not in clusters, and 3) to compare persons with LTBI to those with TB disease.

RESULTS

Significant census tract-level spatial clusters of LTBI and TB disease were identified. Compared with persons with LTBI in non-clustered census tracts, those in clustered census tracts were more likely to be foreign-born and less likely to be of white non-Hispanic ethnicity. Populations in census tract clusters of high LTBI prevalence had greater crowding, persons living in poverty, and persons lacking health care insurance than populations not in clustered census tracts. Persons with LTBI were less likely than those with TB disease to be of Asian ethnicity, and persons with LTBI were more likely than those with TB disease to reside in a clustered census tract.

CONCLUSIONS

Characterizing fine-scale populations at risk for LTBI supports effective and culturally accessible screening and treatment programs.

Treatment of Latent Tuberculosis Infection and Its Clinical Efficacy

The role of the treatment for latent tuberculosis infection (LTBI) has been underscored in the intermediate tuberculosis (TB) burden countries like South Korea. LTBI treatment is recommended only for patients at risk for progression to active TB-those with frequent exposure to active TB cases, and those with clinical risk factors (e.g., immunocompromised patients). Recently revised National Institute for Health and Care Excellence (NICE) guideline recommended that close contacts of individuals with active pulmonary or laryngeal TB, aged between 18 and 65 years, should undergo LTBI treatment. Various regimens for LTBI treatment were recommended in NICE, World Health Organization (WHO), and Centers for Disease Control and Prevention guidelines, and superiority of one recommended regimen over another was not yet established. Traditional 6 to 9 months of isoniazid (6H or 9H) regimen has an advantage of the most abundant evidence for clinical efficacy-60%-90% of estimated protective effect. However, 6H or 9H regimen is related with hepatotoxicity and low compliance. Four months of rifampin regimen is characterized by less hepatotoxicity and better compliance than 9H, but has few evidence of clinical efficacy. Three months of isoniazid plus rifampin was proved equivalence with 6H or 9H regimen in terms of efficacy and safety, which was recommended in NICE and WHO guidelines. The clinical efficacy of isoniazid plus rifapentine once-weekly regimen for 3 months was demonstrated recently, which is not yet introduced into South Korea.

Toward a generation free of tuberculosis: TB disease and infection in individuals of college age in the United States

OBJECTIVES

To assess the magnitude of active TB disease and latent TB infection (LTBI) in young adults of college age.

PARTICIPANTS

Individuals who were aged 18-24 years in 2011 were used as a proxy for college students.

METHODS

Active TB cases reported to the 2011 US National TB Surveillance System (NTSS) were included. LTBI prevalence was calculated from the 2011-2012 National Health and Nutrition Examination Survey. The 2011 American Community Survey was used to calculate population denominators. Analyses were stratified by nativity.

RESULTS

Active TB disease incidence among persons aged 18-24 years was 2.82/100,000, 18.8/100,000 among foreign-born individuals and 0.9/100,000 among US-born individuals. In 2011, 878 TB cases were reported; 629 (71.6%) were foreign-born. LTBI prevalence among persons of 18-24 years was 2.5%: 8.7% and 1.3% among foreign-born and US-born, respectively.

CONCLUSION

Active screening and treatment programs for foreign-born young adults could identify TB cases earlier and provide an opportunity for prevention efforts.

Update: Vaccines in primary immunodeficiency

Vaccines were originally developed to prevent or ameliorate infectious disease. As knowledge of immune function and appreciation of immunodeficiency has developed, researchers have used vaccine responses as a tool to characterize the phenotypes of patients exhibiting various syndromes. Thus it has become possible for a clinician to evaluate individual responses to vaccines to interrogate the immunocompetence of their patients. Although there have been many advances in these areas, we still have much to learn about the quantity and quality of humoral and cellular vaccine responses in healthy and immunodeficient subjects and how that knowledge can then be extrapolated to diagnostic purposes. Adverse effects of vaccines have been recognized for many years, especially the occurrence of infections caused by viable vaccine organisms in immunodeficient hosts. Nevertheless, vaccines are essential for disease prevention in immunodeficient patients, just as they are for healthy subjects. Clinicians must understand the appropriate and safe use of vaccines in patients with immunodeficiency. This review highlights some recent advances and ongoing challenges in application of vaccines for the diagnosis and treatment of immunodeficiencies.

Tuberculosis screening among HIV-infected patients: tuberculin skin test vs. interferon-gamma release assay

National guidelines recommend screening for latent tuberculosis infection (LTBI) in all HIV-infected patients. Thus, the objective of this study was to measure protocol adherence to national guidelines regarding LTBI screening for HIV-infected patients entering care at an urban primary care clinic specializing in HIV care, identify clinical and other characteristics associated with adherence, and determine whether transitioning from the tuberculin skin test (TST) to the interferon-gamma release assay (IGRA) improved adherence. We conducted a retrospective study using protocol adherence to LTBI screening guidelines within twelve months of entering care at an HIV clinic as the primary outcome. Successful protocol adherence was defined as the placement and reading of a TST, performance of an IGRA, or a note in study clinic records documenting prior testing or treatment for tuberculosis in an outside setting. Multivariable modified Poisson regression models were used in analyses. Overall, 32% (n = 118/372) of patients received LTBI screening within twelve months of entering care. Protocol adherence to LTBI screening guidelines increased from 28% to 37% following the transition from TST to IGRA screening. IGRA screening [adjusted prevalence ratio: 1.45, 95% confidence limits: (1.07, 1.96)], male sex [1.47 (1.05, 2.07)], transfer patient status [1.51 (1.05, 2.18)], and greater than one year of clinic attendance [1.62 (1.06, 2.48)] were independently associated with protocol adherence. Among patients without prior LTBI screening or treatment, patients entering the clinic in 2013 under the IGRA screening protocol were more likely to be screened for LTBI compared to patients entering under the TST screening protocol (34.3% vs. 9.7%, p < 0.001). In conclusion, transitioning from TST to IGRA-based screening improved adherence to screening guidelines. However, further work on improving adherence to LTBI screening guidelines among HIV-infected patients is needed.

The Modern Profile of Tuberculosis: Developing the TB Social Survey to understand contemporary social patterns in tuberculosis

Social disparities in tuberculosis have been documented for decades, yet to date there has not been a comprehensive study to examine the contemporary causes of these disparities. Local public health departments, and particularly public health nursing staff are charged with delivering directly observed therapy to individuals with tuberculosis disease. As a result of the frequency and duration of treatment, practitioners delivering therapy are often well-acquainted with the lives and challenges of their constituents. Thus, through these practitioners there exists a deep repository of knowledge on the drivers of social disparities in tuberculosis disease. Partnering with local public health departments, we developed a survey instrument aimed at understanding the social profile of individuals with tuberculosis disease in metropolitan Detroit, Michigan. We discuss the development and implementation of the survey instrument as well as challenges in developing partnerships between academic researchers and local public health practitioners. This study can serve as a framework for both academic researchers and public health practitioners interested in addressing social disparities in infectious disease.

Comparing Drivers and Dynamics of Tuberculosis in California, Florida, New York, and Texas

RATIONALE

There is substantial state-to-state heterogeneity in tuberculosis (TB) in the United States; better understanding this heterogeneity can inform effective response to TB at the state level, the level at which most TB control efforts are coordinated.

OBJECTIVES

To characterize drivers of state-level heterogeneity in TB epidemiology in the four U.S. states that bear half the country's TB burden: California, Florida, New York, and Texas.

METHODS

We constructed an individual-based model of TB in the four U.S. states and calibrated the model to state-specific demographic and age- and nativity-stratified TB incidence data. We used the model to infer differences in natural history of TB and in future projections of TB.

MEASUREMENTS AND MAIN RESULTS

We found that differences in both demographic makeup (particularly the size and composition of the foreign-born population) and TB transmission dynamics contribute to state-level differences in TB epidemiology. The projected median annual rate of decline in TB incidence in the next decade was substantially higher in Texas (3.3%; 95% range, -5.6 to 10.9) than in California (1.7%; 95% range, -3.8 to 7.1), Florida (1.5%; 95% range, -7.4 to 14), and New York (1.9%; 95% range, -6.4 to 9.8). All scenarios projected a flattening of the decline in TB incidence by 2025 without additional resources or interventions.

CONCLUSIONS

There is substantial state-level heterogeneity in TB epidemiology in the four states, which reflect both demographic factors and potential differences in the natural history of TB. These differences may inform resource allocation decisions in these states.