Prevalence of Latent Tuberculosis Infection Among Healthy Young Children and Adolescents and a Two-step Approach for the Diagnosis of Tuberculosis Infection in Chengdu, China.

BACKGROUND: China has a high burden of tuberculosis and latent tuberculosis infection (LTBI). The aim of this study was to estimate the prevalence of LTBI among healthy young children and adolescents and test a 2-step approach to explore the threshold for the diagnosis of tuberculosis infection in Chengdu, China. METHODS: Healthy preschool children and school-going children in Chengdu, Sichuan Province, were screened for LTBI using the tuberculin skin test (TST). Preschool children with TST ≥ 5 mm also underwent interferon-γ release assay (IGRA) to explore the threshold of this 2-step approach. RESULTS: In total, 5667 healthy young children and adolescents completed TST test between July 2020 and January 2021 and were included in the present analysis. The age of the participants ranged from 2.4 to 18 years (median 7.25 ± 4.514 years), of which 2093 (36.9%) were younger than 5 years. The overall prevalence of LTBI was 6.37% and 6.64% in children younger than 5 years old. Fourteen of the 341 preschool children with TST ≥5 mm were interferon-γ release assay positive, of which 4 showed a TST result of 5-10 mm, and 6 preschool children received preventive treatment for LTBI. CONCLUSIONS: Healthy young children and adolescents should also be considered as important target populations for LTBI screening. TST can be recommended for first-line screening as part of a 2-step approach for LTBI screening using a positive threshold of 5 mm.

A screening strategy for latent tuberculosis in healthcare workers: Cost-effectiveness and budget impact of universal versus targeted screening.

OBJECTIVE: To evaluate the clinical, cost-efficiency, and budgetary implications of universal versus targeted latent tuberculosis infection (LTBI) screening strategies among healthcare workers (HCWs) in an intermediate tuberculosis (TB)-burden country. DESIGN: Pragmatic cost-effectiveness and budget impact analysis using decision-analytic modeling. SETTING: A tertiary-care hospital in Singapore. METHODS: We compared 7 potentially implementable LTBI screening programs including universal and targeted strategies with different screening frequencies. Feasible targeting methods included stratification by country of origin (a proxy for risk of prior TB exposure) and by high-risk occupation. The clinical and financial consequences of each strategy were estimated relative to "no screening" (current practice) and compared to locally appropriate cost-effectiveness thresholds. All analyses were conducted from the hospital's perspective over a 3-year time horizon, based on the typical hospital planning period. Parameter uncertainties were accounted for using sensitivity analyses. RESULTS: In our model, relative to current practice, screening new international hires and triennial screening of existing high-risk workers is most cost-effective (US$58 per quality adjusted life year [QALY]) and decreases active TB cases from 19 to 14. Screening all new hires combined with triennial universal screening, with or without annual high-risk screening or annual universal screening, reduced active TB to a range of 19 to 6 cases, but these strategies are less cost-effective and require substantially higher expenditures. CONCLUSIONS: Targeted LTBI screening for HCWs can be highly cost-effective for hospitals in settings similar to Singapore. More inclusive screening strategies (including regular universal screening) can yield better outcomes but are less efficient and may even be unaffordable.

The effectiveness and cost-effectiveness of screening for latent tuberculosis among migrants in the EU/EEA: a systematic review.

BackgroundMigrants account for a large and growing proportion of tuberculosis (TB) cases in low-incidence countries in the European Union/European Economic Area (EU/EEA) which are primarily due to reactivation of latent TB infection (LTBI). Addressing LTBI among migrants will be critical to achieve TB elimination. Methods: We conducted a systematic review to determine effectiveness (performance of diagnostic tests, efficacy of treatment, uptake and completion of screening and treatment) and a second systematic review on cost-effectiveness of LTBI screening programmes for migrants living in the EU/EEA. Results: We identified seven systematic reviews and 16 individual studies that addressed our aims. Tuberculin skin tests and interferon gamma release assays had high sensitivity (79%) but when positive, both tests poorly predicted the development of active TB (incidence rate ratio: 2.07 and 2.40, respectively). Different LTBI treatment regimens had low to moderate efficacy but were equivalent in preventing active TB. Rifampicin-based regimens may be preferred because of lower hepatotoxicity (risk ratio = 0.15) and higher completion rates (82% vs 69%) compared with isoniazid. Only 14.3% of migrants eligible for screening completed treatment because of losses along all steps of the LTBI care cascade. Limited economic analyses suggest that the most cost-effective approach may be targeting young migrants from high TB incidence countries. Discussion: The effectiveness of LTBI programmes is limited by the large pool of migrants with LTBI, poorly predictive tests, long treatments and a weak care cascade. Targeted LTBI programmes that ensure high screening uptake and treatment completion will have greatest individual and public health benefit.

Use of tuberculin skin test for assessment of immune recovery among previously malnourished children in Ethiopia.

OBJECTIVE: To compare levels of immunity in children recovering from severe acute malnutrition (cases) against those of community controls (controls). RESULTS: At baseline children recovering from severe acute malnutrition had lower, mid upper arm circumference (122 mm for cases and 135 mm for controls; p < 0.001), weight-for-height Z-score (- 1.0 for cases and - 0.5 for controls; p < 0.001), weight-for-age Z-score (- 2.8 for cases and - 1.1 for controls; p < 0.001) and height/length-for-age Z-score (- 3.6 for cases and - 1.4 for controls; p < 0.001), than controls. Age and gender matched community controls. At baseline, prevalence of a positive tuberculin skin test, assessed by cutaneous delayed-type hypersensitivity reaction skin test, was very low in both cases (3/93 = 3.2%) and controls (2/94 = 2.1%) and did not significantly increase at 6 months follow up (6/86 = 7.0% in cases and 3/84 = 3.4% in controls). The incidences of common childhood morbidities, namely fever, diarrhoea and cough, were 1.7-1.8 times higher among cases than controls. In conclusion, these results show that tuberculin skin test does not enable any conclusive statements regarding the immune status of patients following treatment for severe acute malnutrition. The increased incidence of infection in cases compared to controls suggests persistence of lower resistance to infection even after anthropometric recovery is achieved.

Tuberculin skin test and interferon-gamma release assay use among privately insured persons in the United States.

OBJECTIVE: To describe tuberculin skin test (TST) and interferon-gamma release assay (IGRA) (i.e., QuantiFERON®-TB [QFT] and T-SPOT®.TB [T-SPOT]) use among privately insured persons in the United States over a 15-year period. METHODS: We used current procedural terminology (CPT) codes for the TST and IGRAs to extract out-patient claims (2000-2014) and determined usage (claims/100 000). The χ2 test for trend in proportions was used to describe usage trends for select periods. RESULTS: The TST was the dominant (>80%) test in each year. Publication of guidelines preceded the assignment of QFT and T-SPOT CPT codes by 1 year (2006 for QFT; 2011 for T-SPOT). QFT usage was higher (P < 0.01) than T-SPOT in each year. The average annual increase in the use of QFT was higher than that of T-SPOT (35 vs. 3.8/100 000), and more so when the analytic period was 2011-2014 (65 vs. 38/100 000). However, during that 4-year period (2011-2014), TST use trended downward, with an average annual decrease of 28/100 000. The annual proportion of enrollees tested ranged from 1.1% to 1.5%. CONCLUSIONS: These results suggest a gradual shift from the use of the TST to the newer IGRAs. Future studies can assess the extent, if any, to which the shift from the use of the TST to IGRAs evolved over time.

Status of Tuberculosis services in Indian Prisons.

INTRODUCTION: Prisons are known to be a high risk environment for tuberculosis (TB) due to overcrowding, low levels of nutrition, poor infection control and lack of accessible healthcare services. India has nearly 1400 prisons housing 0.37 million inmates. However, information on, availability of diagnostic and treatment services for TB in the prison settings is limited. This study examined the availability of TB services in prisons of India. Simultaneously, prison inmates were screened for tuberculosis. METHOD: The study was conducted in 157 prisons across 300 districts between July-December 2013. Information on services available and practices followed for screening, diagnosis and treatment of TB was collected. Additionally, the inmates and prison staff were sensitised on TB using interpersonal communication materials. The inmates were screened for cough ≥2 weeks as a symptom of TB. Those identified as presumptive TB patients (PTBP) were linked with free diagnostic and treatment services. RESULTS: Diagnostic and treatment services for TB were available in 18% and 54% of the prisons respectively. Only half of the prisons screened inmates for TB on entry, while nearly 60% practised periodic screening of inmates. District level prisons (OR, 6.0; 95% CI, 1.6-22.1), prisons with more than 500 inmates (OR, 52; 95% CI, 1.4-19.2), and prisons practising periodic screening of inmates (OR, 2.7; 95% CI, 1.0-7.2) were more likely to diagnose TB cases. 19% of the inmates screened had symptoms of TB (cough ≥2 weeks) and 8% of the PTBP were diagnosed with TB on smear microscopy. CONCLUSION: The TB screening, diagnostic and treatment services are sub-optimal in prisons in India and need to be strengthened urgently.

Mycobacterium Tuberculosis Infection, Immigration Status, and Diagnostic Discordance: A Comparison of Tuberculin Skin Test and QuantiFERON-TB Gold In-Tube Test Among Immigrants to the U.S.

OBJECTIVE: We used a recent source of nationally representative population data on tuberculosis (TB) infection to characterize concordance between the tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube (QFT-GIT) blood test for immigrants in the United States. METHODS: We used TB screening data from the 2011-2012 National Health and Nutrition Examination Survey to examine concordance between the TST and QFT-GIT--an interferon-gamma release assay (IGRA) blood test--for 7,097 U.S. natives, naturalized citizens, and noncitizens. RESULTS: Consistent with prior findings, one in five immigrants in the survey was identified with latent TB infection (LTBI), a rate 14 times higher than for U.S. natives. We also found higher rates of discordant TST/IGRA results among immigrants than among U.S. natives. Unadjusted discordance between TST and IGRA was 3% among U.S. natives (weighted N=5,684,274 of 191,179,213) but ranged up to 19% for noncitizens (weighted N=3,722,960 of 19,377,147). Adjusting for age, sex, and race/ethnicity, noncitizens had more than nine times the odds of having a positive TST result but negative QFT-GIT result compared with U.S. natives. CONCLUSIONS: Our findings suggest that whether and how either of these tests should be deployed is highly context sensitive. Significant discordance in test results when used among immigrants raises the possibility of missed opportunities for harm reduction in this already at-risk population. However, we found little distinction between the tests in terms of diagnostic outcome when used in a U.S. native population, suggesting little benefit to the adoption and use of the QFT-GIT test in place of TST on the basis of test performance alone for this population.

Market assessment of tuberculosis diagnostics in South Africa, 2012-2013.

OBJECTIVE: To assess the current served available market of tuberculosis (TB) diagnostics in South Africa in the public and private sectors. DESIGN: Public and private sector test volumes and unit costs were collected for tuberculin skin tests, interferon-gamma release assays, smear microscopy, culture, speciation, Xpert MTB/RIF, other nucleic acid amplification tests, drug susceptibility testing and adenosine deaminase tests. RESULTS: In 2012, during Xpert scale-up, the public and private sectors performed a total of 9.2 million TB diagnostic tests, at an estimated total value of US$98 million. The public sector accounted for 93% of the overall test volume and value. There were no major differences in the types of tests performed in both sectors, with microscopy and culture accounting for the majority of tests performed (72%). In 2013, the public sector market value increased to US$101 million (a 10% increase over 2012): Xpert volumes increased by 166%, while total TB test volumes decreased by 12% compared to 2012. CONCLUSION: South Africa has a substantial TB diagnostic market in terms of both volume and value. The roll-out of Xpert provides insights into how markets change in volume and value with the introduction of new tools.

The outcome of a cohort of tuberculin-positive predominantly South Asian new entrants aged 16-34 to the UK: Blackburn 1989-2001.

SETTING: Blackburn, Hyndburn and Ribble Valley Local Government areas of England and Wales, the former a high tuberculosis (TB) prevalence district. BACKGROUND: The incidence of tuberculosis in new entrants aged 16-34 with positive tuberculin skin tests but normal chest X-rays after initial entry is not definitely known, and was previously estimated from cross-sectional national surveys and derived data for the 2006 and 2011 NICE economic appraisals of new entrant TB screening. METHODS: New entrants aged 16-34 years predominantly from South Asia (India, Pakistan and Bangladesh), with tuberculin tests inappropriately positive for their BCG history were identified for the years 1989-2001 inclusive from a new entrant database. These entrants were compared with the current GP registration database to see if local residence could be confirmed and the local TB notification database to October 2008. Survival analysis was carried out using Kaplan-Meier survival curves and a Cox Regression model. RESULTS: Four hundred and seventy-nine such new entrants with normal initial chest X-rays were identified. Of these 402 (84%) registered with a General Practitioner in East Lancashire for a period of time and could be followed up by this study. The crude incidence density of active TB amongst these individuals with latent disease was 1297 per 100 000 person-years (95% CI; 991-1698 per 100 000 person-years). After 10 and 15 years of follow-up 13.5 and 16.3% of individuals, respectively, had progressed on to active disease. CONCLUSION: This patient-derived, rather than estimated, data shows a minimum risk of TB disease of 16.3% at 15 years. The 2006 NICE economic appraisal, suggested that treatment for latent TB infection (LTBI) was cost-effective when the incidence of clinical TB over 15 years surpassed 18% in these populations. The 2011 NICE economic appraisal reduced this to 12% active TB over 15 years, and showed that at 16% active TB over 15 years a single interferon gamma release assay was the most cost-effective strategy. Further cohort studies are urgently needed to confirm or revise the assumptions behind the 2011 NICE economic appraisal.

[Socio-economic status and duration of TB symptoms in males treated at the Mazovian Treatment Centre of Tuberculosis and Lung Diseases in Otwock]. / Status spoleczno-ekonomiczny i czas trwania objawów u mezczyzn chorych na gruzlice leczonych w Mazowieckim Centrum Leczenia Chorób Pluc i Gruzlicy w Otwocku.

INTRODUCTION: The incidence of tuberculosis depends on many factors, not only on health issues but also on socioeconomic factors. The aim of this study was to assess the duration of symptoms and the extent of radiological changes in men with bacteriologically confirmed pulmonary tuberculosis in relation to their socioeconomic status. MATERIAL AND METHODS: This was a retrospective study based on the analysis of 300 hospital records of patients hospitalised in 2004-2006 in the male ward of the Mazovian Treatment Centre of Lung Diseases and Tuberculosis in Otwock. In all patients, the diagnosis of tuberculosis was bacteriologically confirmed. We evaluated the duration of symptoms prior to hospitalisation, the extent of radiological changes and socioeconomic status. We also took into account the place of residence, professional activity, age and marital status. RESULTS: Among patients with TB hospitalised in the Mazovia Region, 74% were professionally inactive persons and 57% were unemployed. Patients population in cities and villages were similar, but as much as 10% of the patients hospitalised who were actively spreading bacilli in Mazovia Region were homeless. In the study group, 60% of the men were unmarried. In 63% of the patients symptoms of tuberculosis were present for more than two months. Chronic symptoms were reported more often in the unemployed (60%) and in single patients. As much as 81% of the patients at the initiation of treatment, had extensive radiological changes in 3 or more lung fields. Quite often sweeping pulmonary changes were observed in the homeless, unemployed and pensioners. Sputum smear-positive tuberculosis, was demonstrated in 87% of the examined patients. CONCLUSIONS: The incidence of tuberculosis observed in the Mazovia Region was especially observed in the unemployed, disabled and pensioners. Among these patients, many were homeless. The majority of patients in Mazovia Region at the start of treatment already had very extensive radiological changes and the symptoms were present with them for several weeks.

Moving toward tuberculosis elimination: implementation of statewide targeted tuberculin testing in Tennessee.

RATIONALE: From 1993 to 2010, annual U.S. tuberculosis (TB) rates declined by 58%. However, this decline has slowed and disproportionately occurred among U.S.-born (78%) versus foreign-born persons (47%). Addressing the high burden of latent TB infection (LTBI) must be prioritized. OBJECTIVES: Only Tennessee has implemented a statewide program for finding and treating people with LTBI. The program was designed to address high statewide TB rates and growing burden among the foreign-born. We sought to assess the feasibility and yield of Tennessee's program. METHODS: Analyzing data from the 4.8-year period from program inception in March 2002 through December 2006, we quantified patients screened using a TB risk assessment tool, tuberculin skin tests (TST) placed and read, TST results, and patients initiating and completing LTBI treatment. We then estimated the number needed to screen to find and treat one person with LTBI and to prevent one case of TB. MEASUREMENTS AND MAIN RESULTS: Of 168,517 persons screened, 102,709 had a TST placed and read. Among 9,090 (9%) with a positive TST result, 53% initiated treatment, 54% of whom completed treatment. An estimated 195 TB cases were prevented over the 4.8 years analyzed, and program performance measures improved annually. The number of TSTs placed to prevent one TB case ranged from 150 for foreign-born persons to 9,834 for persons without TB risk. CONCLUSIONS: Targeted tuberculin testing and LTBI treatment is feasible and likely to reduce TB rates over time. Yield and cost-effectiveness are maximized by prioritizing foreign-born persons, a large population with high TB risk.

Interferon-gamma release assays for the diagnosis of extrapulmonary tuberculosis: a systematic review and meta-analysis.

Interferon -gamma release assays (IGRAs) provide a new diagnostic method for Mycobacterium tuberculosis (TB) infection. However, the diagnostic value of IGRAs for extrapulmonary TB (EPTB) has not been clarified. We searched several databases and selected papers with strict inclusion criteria, evaluated the evidence of commercially available IGRAs (QuantiFERON(®) -TB Gold QFT-G or QFT-GIT and T-SPOT(®) .TB) on blood and the tuberculin skin test (TST) using random effects models. Twenty studies with 1711 patients were included. After excluding indeterminate results, pooled sensitivity for the diagnosis of EPTB was 72% [95% confidence interval (CI) 65-79%] for QFT-G or GIT and 90% (95% CI, 86-93%) for T-SPOT; in high-income countries the sensitivity of QFT-G or GIT (79%, 95% CI 72-86%) was much higher than that (29%, 95% CI 14-48%) in low/middle-income countries. Pooled specificity for EPTB was 82% (95% CI 78-87%) for QFT-G or GIT and 68% (95% CI 64-73%) for T-SPOT. Pooled sensitivity of TST from four studies in high-income countries was lower than that of IGRAs. T-SPOT was more sensitive in detecting EPTB than QFT-G or GIT and TST. However, both IGRAs and TST have similar specificity for EPTB. IGRAs have limited value as diagnostic tools to screen and rule out EPTB, especially in low/middle-income countries. The immune status of patients does not affect the diagnostic accuracy of IGRAs for EPTB.

Tuberculin skin test: operational research in the state of Mato Grosso do Sul, Brazil.

OBJECTIVE: To investigate operational aspects of tuberculin skin test (TST) use in tuberculosis control programs and at specialized Brazilian National Sexually Transmitted Diseases/AIDS and Viral Hepatitis Program health care clinics in priority municipalities for tuberculosis control in the state of Mato Grosso do Sul, Brazil. METHODS: This was a descriptive, cross-sectional, epidemiological survey. Data on qualifications/training of professionals administering TSTs, timing of the TST, procedures in cases of loss to follow-up (reading), material availability, and material storage were collected through interviews and technical visits. For the 2008-2009 period, we determined the numbers of screenings in vulnerable populations, of TSTs performed, and of patients treated for latent tuberculosis. RESULTS: We interviewed 12 program managers in six municipalities. Some programs/clinics did not perform TSTs. Nursing teams administered the TSTs, results were read by non-specialists, and specialization/refresher courses were scarce. The PPD RT23 was stored in 5-mL flasks under appropriate conditions. Insulin syringes were commonly used. Testing was available during business hours, three times a week. In cases of loss to follow-up, telephone calls or home visits were made. Of the 2,305 TSTs evaluated, 1,053 (46%) were performed in indigenous populations; 831 (36%) were screenings in prisons, performed for training; and only 421 (18%) involved contacts of tuberculosis patients or vulnerable populations. Four vulnerable patients and 126 indigenous subjects were treated for latent tuberculosis. CONCLUSIONS: These priority municipalities showed operational difficulties regarding human resources, materials, and data records.

Evaluation of a school-based program for diagnosis and treatment of latent tuberculosis infection in immigrant children.

OBJECTIVE: To evaluate a 10-year school-based latent tuberculosis infection (LTBI) screening program, targeting immigrant children in Montreal, Canada, and to identify predictive factors for refusal and, poor adherence to treatment. METHODS: Immigrant children were screened for LTBI with Tuberculin Skin Test (TST). Isoniazid was, given when LTBI was diagnosed. Predictors of LTBI, of refusal of follow-up and treatment and of poor, adherence to isoniazid were analyzed. RESULTS: Four thousand three hundred and seventy-five children were offered screening, 82.3% consented to TST and 22.8% were positive. An, older age at migration (odds ratio (OR)=1 [95% CI: 1.0-1.01]), as well as migration from a none, established market economy country (OR varying from 2.41 to 4.23) were significantly associated with, positive TST. Among positive children, further evaluation was refused in 5.7%, mainly in migrants from, Eastern Europe (OR=4.05 [95% CI: 2.14-7.69]). Refusal of treatment (11.2%) was more frequent in, Eastern European when compared to South-eastern Asian (OR=6.91 [95% CI: 1.56-30.75]), in, blended families (OR=3.25 [95% CI: 1.25-8.46]) and when the first visit to hospital was delayed (OR=1.01 [95% CI: 1.0-1.02]). Adequate completion of treatment was noted in 61.3%. Age>16 years (OR=1.82 [95% CI: 1.82-2.99]), a delay between TST and first visit>15 days (OR=1.6 [95% CI: 1.12-2.28]), as well as the presence of relative>18 years in the household (OR=1.56 [95% CI: 1.0-2.43]), were associated with poor adherence to treatment. CONCLUSION: Sociocultural and behavioural factors are involved in acceptance of LTBI treatment in, immigrant children. Adherence to treatment is challenging and requires comperhension of sociocultural beliefs and accessibility to TB clinic.

Challenges to tuberculin screening and follow-up in an urban Aboriginal sample in Montreal, Canada.

We sought to describe the prevalence and predictors of tuberculin skin test (TST) reactors in a high-risk sample of urban Aboriginal people, and to evaluate adherence to medical evaluation and latent tuberculosis infection (LTBI) treatment among those with TST reactivity. Of the 164 participants tested, 86% returned for TST reading. Positive TST reactions (>or=10 mm) were observed in 17.7% (25/141, 95% CI 11.4-24.0) of participants, and were associated with older age (OR per 10 year increase 1.8, 95% CI 1.2-2.7) and Inuit Aboriginal group (OR 2.8, 95% CI 1.1-7.3). Only four participants presented for evaluation, of whom one initiated and none completed LTBI treatment. Tuberculin screening in this population can be an effective strategy for identifying TST reactive individuals; however, screening efforts will have minimal impact without additional efforts in this high-risk group.

Tuberculin reactivity among health care workers in nonhospital settings.

BACKGROUND: We used workers' compensation data to identify health care workers at risk of tuberculosis exposure in the hospital and nonhospital environment. METHODS: We identified State Fund workers' compensation claims having a documented tuberculin skin test (TST) conversion (size >or=10 mm) with a previous negative skin test between 1996 and 2000 in the State of Washington. RESULTS: Health care workers experienced an overall accepted workers' compensation claim rate of 2.3 claims/10,000 full-time equivalent employees (FTEs) per year for tuberculin reactivity. Receptionists accounted for the largest number, with 18.4% tuberculin reactivity claims. The number of tuberculin reactivity claims was the highest for offices and clinics of doctors of medicine (3.7 per 10,000 FTEs), followed by medical laboratories (2.6 per 10,000 FTEs). CONCLUSION: This study allowed characterization of employees in various nonhospital health services locations with higher number of tuberculin reactivity.

A university hospital's 10-year experience with tuberculin testing: value of the 2-step tuberculin skin test.

BACKGROUND: The usefulness of the 2-step tuberculin skin test as a tool for monitoring tuberculosis exposure among health care workers is controversial. OBJECTIVES: We aimed to determine the cost-effectiveness and influence of initiation of a preemployment, 2-step tuberculin skin-testing program on the annual tuberculin skin conversion rate among a university hospital's health care workers. METHODS: The tuberculin skin test conversion rates among the recipients of 31,729 tuberculin skin tests over 10 years were retrospectively analyzed. Data from the first 6 years of this study were generated when a single preemployment tuberculin skin test was utilized. Data from the last 4 years were gathered after the advent of a preemployment 2-step program. A cost analysis of the 2-step tuberculin skin test process was performed to determine the annual cost of this program. RESULTS: Relative risk of a conversion was 8.43 times less during the 2-step period when compared with the years when a single tuberculin skin test was given at the start of employment (P < .001). A cost analysis showed that the annual added cost of the 2-step program was approximately 9,565 US dollars. CONCLUSION: A greater than 8-fold reduction in the number of annual tuberculin skin test conversion coincided with, but could not be attributed solely to, the initiation of a 2-step program in our hospital. The Infection Control Committee concluded that the 2-step testing program is essential to achieve the hospital's goal of a 0% annual tuberculin skin test conversion rate and that the annual cost is justified.

A statewide assessment of tuberculin skin testing of preschool children enrolled in medicaid managed care.

OBJECTIVES: This study examined tuberculosis screening among preschool children enrolled in a statewide Medicaid managed care program. METHODS: A random sample of 2,000 was selected from 19 to 35 month old children who were continuously enrolled in Rhode Island's Medicaid managed care program for 1 year. Sociodemographic data were obtained from computerized administrative databases. Medical record audits were performed to obtain the dates and results of tuberculosis tests. RESULTS: Data from the medical record audits were available for 1,988 of the study children. For 1,215 of the study children (1,215/1,988 = 61%) a tuberculin skin test had been performed, but a reading was only documented for 736 children (60% of children who received a tuberculin skin test) and only one child tested positive (0.1%). CONCLUSIONS: A majority of preschool children in this population in which the prevalence of risk factors for tuberculosis is likely to be relatively high did have a tuberculosis test performed. However, in many cases the tuberculin skin test was either not read or the results not documented. The low rate of positivity is consistent with current AAP guidelines for selective tuberculin skin testing.

Cost-effectiveness of tuberculosis control strategies among immigrants and refugees.

Today, in Western Europe, Canada and the USA, more than half of all new active tuberculosis (TB) cases occur among foreign-born migrants. This article examines the impact of migration from high TB-incidence to low TB-incidence countries, and compares the cost-effectiveness of different TB control strategies. A Medline search was conducted to identify relevant English language publications prior to December 2003. Additional articles were identified from the reference lists from these publications. Despite the high proportion of active cases in low-incidence countries attributable to foreign-born residents, the public health impact is relatively low. Current chest radiograph screening programmes have little impact and are not cost-effective. Screening with sputum culture would improve cost-effectiveness marginally. Treatment of latent infection detected through screening with tuberculin skin testing or chest radiographs may require coercive measures to maximise impact and cost-effectiveness. In contrast, contact tracing, particularly within ethnic communities, appears to be more cost-efficient and less intrusive. In low-incidence countries, screening of migrants at entry has little overall impact and is not a very cost-effective tuberculosis control strategy. More effective alternatives include contact tracing delivered through primary care and increased investment in global tuberculosis control.