Treatment completion for latent tuberculosis infection in Norway: a prospective cohort study

A Mathematical Model for the Impact of 3HP and Social Programme Implementation on the Incidence and Mortality of Tuberculosis: Study in Brazil

In this paper, we presented a mathematical model for tuberculosis with treatment for latent tuberculosis cases and incorporated social implementations based on the impact they will have on tuberculosis incidence, cure, and recovery. We incorporated two variables containing the accumulated deaths and active cases into the model in order to study the incidence and mortality rate per year with the data reported by the model. Our objective is to study the impact of social program implementations and therapies on latent tuberculosis in particular the use of once-weekly isoniazid-rifapentine for 12 weeks (3HP). The computational experimentation was performed with data from Brazil and for model calibration, we used the Markov Chain Monte Carlo method (MCMC) with a Bayesian approach. We studied the effect of increasing the coverage of social programs, the Bolsa Familia Programme (BFP) and the Family Health Strategy (FHS) and the implementation of the 3HP as a substitution therapy for two rates of diagnosis and treatment of latent at 1% and 5%. Based of the data obtained by the model in the period 2023-2035, the FHS reported better results than BFP in the case of social implementations and 3HP with a higher rate of diagnosis and treatment of latent in the reduction of incidence and mortality rate and in cases and deaths avoided. With the objective of linking the social and biomedical implementations, we constructed two different scenarios with the rate of diagnosis and treatment. We verified with results reported by the model that with the social implementations studied and the 3HP with the highest rate of diagnosis and treatment of latent, the best results were obtained in comparison with the other independent and joint implementations. A reduction of the incidence by 36.54% with respect to the model with the current strategies and coverage was achieved, and a greater number of cases and deaths from tuberculosis was avoided.

Current Status of Latent Tuberculosis Infection Treatment Among Pediatric Patients in Korea: Prescription and Treatment Completion

BACKGROUND

The treatment of pediatric patients with latent tuberculosis infection (LTBI) is a crucial TB control strategy. LTBI is not a reportable communicable disease, and data regarding LTBI treatment in pediatric patients in Korea are scarce. This study aimed to investigate the prescription patterns and treatment completion rates among pediatric patients with LTBI in Korea by analyzing National Health reimbursement claims data.

METHODS

We retrospectively analyzed outpatient prescription records for pediatric patients aged 18 or younger with LTBI-related diagnostic codes from 2016 to 2020. We compared the frequency of prescriptions for the standard treatment regimen (9 months of isoniazid [9H]) and an alternative treatment regimen (3 months of isoniazid plus rifampicin [3HR]). We also assessed the treatment incompletion rates by age group, treatment regimen, treatment duration, the level of medical facility, physician's specialty, and hospital location. We performed multivariable analysis to identify factors influencing treatment incompletion.

RESULTS

Among the 11,362 patients who received LTBI treatment, 6,463 (56.9%) were prescribed the 9H regimen, while 4,899 (43.1%) received the 3HR regimen. Patients in the 3HR group were generally older than those in the 9H group. The proportion of 3HR regimen prescriptions significantly greater in the later period (2018-2020), in primary hospitals, under the management of non-pediatric specialists, and in metropolitan regions. The overall treatment incompletion rate was 39.7% (9H group: 46.9%, 3HR group: 30.3%). In the multivariable analysis, 9H regimen prescription was the strongest factor associated with treatment incompletion (adjusted odds ratio, 2.42; 95% confidence interval, 2.20-2.66; P < 0.001). Additionally, management in a primary hospital, a hospital's location in a non-metropolitan region, and management by a non-pediatric specialist were also significant risk factors for treatment incompletion.

CONCLUSION

Our study results suggest that promoting the use of 3HR regimen prescriptions could be an effective strategy to enhance treatment completion. Physicians in primary hospitals, hospitals located in non-metropolitan regions, and physicians without a pediatric specialty require increased attention when administering LTBI treatment to pediatric patients to ensure treatment completion.

Exploring health information system resilience during COVID-19 pandemic: case studies from Norway, Sri Lanka & Rwanda

The study aims at exploring health system resilience by defining the scope on health information systems, one of the six building blocks of the health system. The empirical evidence is derived using qualitative data collection and analysis in the context of Norway, Sri Lanka and Rwanda during the COVID-19 pandemic. The case studies elicit bounce back and bounce forward properties as well as the agility as major attributes of resilience present across the countries. Existing local capacity, networking and collaborations, flexible digital platforms and enabling antecedent conditions are identified as socio-technical determinants of information system resilience based on the case studies across the countries.

Latent Tuberculosis Treatment among Hard-to-Reach Ethiopian Immigrants: Nurse-Managed Directly Observed versus Self-Administered Isoniazid Therapy

BACKGROUND

The treatment of latent tuberculosis infection (LTBI) among high-risk populations is an essential component of Tuberculosis (TB) elimination. However, non-compliance with LTBI treatment remains a major obstacle hindering TB elimination efforts. We have previously reported high treatment compliance with nurse-managed, twice-weekly, directly observed Isoniazid treatment (DOT) for LTBI among hard-to-reach Ethiopian immigrants (EI's).

OBJECTIVES

to compare rate of completion of treatment, cost, and major adverse drug events with daily self-administered Isoniazid treatment (SAT) to nurse-managed Isoniazid DOT among hard-to-reach EIs.

MATERIALS AND METHODS

We conducted a retrospective study and compared self-administered LTBI treatment outcomes among EIs housed in reception centers during 2008-2012 to EIs treated with DOT.

RESULTS

Overall, 455 EIs were included (231 DOT, 224 SAT) in the study. We found no significant difference in treatment completion rates between the two groups (93.0% DOT vs. 87.9% SAT, p = 0.08). However, cases of grade III, drug-induced hepatitis were significantly fewer and treatment costs were significantly lower with the nurse-managed DOT compared with SAT (0% vs. 2.2%, p = 0.028, 363 vs. 521 United States Dollars, p < 0.001, respectively).

CONCLUSIONS

Nurse-managed, twice-weekly DOT among hard-to-reach EIs housed in reception centers had less severe drug-related adverse events and reduced treatment cost compared with daily isoniazid SAT, yet we found no significant difference in treatment completion between the two strategies in this population.

Effectiveness of women-led community interventions in improving tuberculosis preventive treatment in children: results from a comparative, before-after study in Ethiopia

OBJECTIVES

Our objective was to evaluate the impact of a service delivery model led by membership-based associations called Iddirs formed by women on tuberculosis preventive treatment (TPT) initiation and completion rates among children.

DESIGN

Comparative, before-and-after study design.

SETTING

Three intervention and two control districts in Ethiopia.

PARTICIPANTS

Children who had a history of close contact with adults with infectious forms of tuberculosis (TB). Child contacts in whom active TB and contraindications to TPT regimens were excluded were considered eligible for TPT.

INTERVENTIONS

Between July 2020 and June 2021, trained women Iddir members visited households of index TB patients, screened child household contacts for TB, provided education and information on the benefits of TPT, linked them to the nearby health centre and followed them at home for TPT adherence and side effects. Two control zones received the standard of care, which comprised of facility-based provision of TPT to children. We analysed quarterly TPT data for treatment initiation and completion and compared intervention and control zones before and after the interventions and tested for statistical significance using Poisson regression.

PRIMARY AND SECONDARY OUTCOME MEASURES

There were two primary outcome measures: proportion of eligible children initiated TPT and proportion completed treatment out of those eligible.

RESULTS

TPT initiation rate among eligible under-15-year-old children (U15C) increased from 28.7% to 63.5% in the intervention zones, while it increased from 34.6% to 43.2% in the control zones, and the difference was statistically significant (p<0.001). TPT initiation rate for U5C increased from 13% (17 out of 131) to 93% (937 out of 1010). Of the U5C initiated, 99% completed treatment; two discontinued due to side effects; three parents refused to continue; and one child was lost to follow-up.

CONCLUSION

Women-led Iddirs contributed to significant increase in TPT initiation and completion rates. The model of TPT delivery should be scaled-up.

Effect of different interventions for latent tuberculosis infections in China: a model-based study

BACKGROUND

Tuberculosis (TB) has a serious impact on people's health. China is one of 30 countries that has a high TB burden. As the currently decreasing speed of the incidence of TB, the WHO's goal of "End TB Strategy" is hard to achieve by 2035. As a result, a SEIR model that determines the impact of different tuberculosis preventive treatments (TPTs) in different age groups, and the effect of different interventions on latent TB infections (LTBIs) in China is developed.

METHODS

A Susceptible-Exposed-Infectious-Recovered (SEIR) model was established. Goodness-of-fit tests were used to assess model performance. Predictive analysis was used to assess the effect of different interventions on LTBIs and achieving the goals of the "End TB Strategy".

RESULTS

The Chi-square test indicated the model provided a good statistical fit to previous data on the incidence of TB (χ² = 0.3085, p > 0.999). The 1HP treatment regimen (daily rifapentine + isoniazid for 4 weeks) was most effective in reducing the number of TB cases by 2035. The model indicated that several strategies could achieve the 2035 target of the "End TB Strategy": completion of active case finding (ACF) for LTBI and TPT nation-wide within 5 years; completion of ACF for LTBIs and TPT within 2 years in high-incidence areas; completion of TPT in the elderly within 2 years; or introduction of a new vaccine in which the product of annual doses and vaccine efficiency in the three age groups above 14 years old reached 10.5 million.

CONCLUSION

The incidence of TB in China declined gradually from 2005 to 2019. Implementation of ACF for LTBIs and TPT nation-wide or in areas with high incidence, in the elderly, or administration of a new and effective vaccine could greatly reduce the number of TB cases and achieve the 2035 target of the "End TB Strategy" in China.

Use of Isoniazid Monotherapy in Comparison to Rifamycin-Based Regimen for the Treatment of Patients With Latent Tuberculosis: A Systematic Review

Tuberculosis (TB) is a common infectious disease that is present all around the world. This insidious disease needs drastic measures for its eradication. One of the actions contributing to it is the timely diagnosis and offering suitable treatment options for latent tuberculosis patients. In this review, we will discuss and compare the variety of options available for this purpose. We searched PubMed/Medline, Cochrane library, Google Scholar, and Science Direct to find articles regarding the effectiveness, safety, and completion of any of the five regimens available for latent tuberculosis infection. These options are the most classic and standard nine months of isoniazid given daily, which is now more commonly given as six months course, three months of daily isoniazid and rifampin, three months of weekly isoniazid and rifapentine, and four months of daily rifampin. We looked into free full-text studies published from 2011 to 2021 available in English language and human studies. After applying inclusion/exclusion criteria and removing duplicates and screening, 34 articles were shortlisted for quality assessment check, after which we finalized nine studies. Cochrane risk-of-bias assessment tool was used for quality check of randomized control trials, New-Castle Ottawa tool for observational studies, and assessment of multiple systematic reviews (AMSTAR) tool for systematic reviews. Efficacy was checked by tracking down the new cases of TB in the sample population that took the treatment for latent tuberculosis infection. New rifamycin-based regimens were almost equal in effectiveness to isoniazid regimens. The side effect profile is different for both regimens, but short-duration courses tend to have a higher chance of completion.

Effect of implementation of a 12 dose once-weekly treatment (3HP) in addition to standard regimens to prevent TB on completion rates: Interrupted time series design

OBJECTIVE

We aimed to determine if offering a 12 dose once-weekly treatment (3HP) as an additional treatment option would result in an increase in the overall proportion of patients completing TB preventive treatment (TPT) above the baseline rate.

METHODS

We analyzed outcomes in consecutive adults referred to a TB clinic from January 2010 to May 2019. Starting December 2016, 3HP was offered as an alternative to standard clinic regimens which included 9 months of daily isoniazid or 4 months of daily rifampin. The primary outcome was the proportion who completed TPT among all patients who started treatment. Using segmented autoregression analysis we compared completion at the end of the study to projected completion had the intervention not been introduced.

RESULTS

A total of 2803 adults were referred for assessment over the study period. There was an absolute increase in completions among all of those who started a treatment of 19.0% at the end of the study between the observed intervention completion rate and the projected completion rate from the baseline study period (the completion rate had the 3HP intervention not been introduced) (76% observed vs 57% projected, 95% CI 6.6 to 31.4%, p = 0.004) and an absolute increase among those who were offered treatment of 17.3% 95% CI, 2.3 to 32.3%, p = 0.025).

INTERPRETATION

The introduction of 3HP for TPT as an alternative to the regular regimens offered resulted in a significant increase in the proportion of patients completing treatment. Our study provides evidence to support accelerated use of 3HP in Canada.

Modeling the Cost-Effectiveness of Latent Tuberculosis Screening and Treatment Strategies in Recent Migrants to a Low-Incidence Setting

Many tuberculosis (TB) cases in low-incidence settings are attributed to reactivation of latent TB infection (LTBI) acquired overseas. We assessed the cost-effectiveness of community-based LTBI screening and treatment strategies in recent migrants to a low-incidence setting (Australia). A decision-analytical Markov model was developed that cycled 1 migrant cohort (≥11-year-olds) annually over a lifetime from 2020. Postmigration/onshore and offshore (screening during visa application) strategies were compared with existing policy (chest x-ray during visa application). Outcomes included TB cases averted and discounted cost per quality-adjusted life-year (QALY) gained from a health-sector perspective. Most recent migrants are young adults and cost-effectiveness is limited by their relatively low LTBI prevalence, low TB mortality risks, and high emigration probability. Onshore strategies cost at least $203,188 (Australian) per QALY gained, preventing approximately 2.3%-7.0% of TB cases in the cohort. Offshore strategies (screening costs incurred by migrants) cost at least $13,907 per QALY gained, preventing 5.5%-16.9% of cases. Findings were most sensitive to the LTBI treatment quality-of-life decrement (further to severe adverse events); with a minimal decrement, all strategies caused more ill health than they prevented. Additional LTBI strategies in recent migrants could only marginally contribute to TB elimination and are unlikely to be cost-effective unless screening costs are borne by migrants and potential LTBI treatment quality-of-life decrements are ignored.

Initiation and completion of treatment for latent tuberculosis infection in migrants globally: a systematic review and meta-analysis

Background

Latent tuberculosis infection (LTBI) is one of the most prevalent infections globally and can lead to the development of active tuberculosis disease. In many low-burden countries, LTBI is concentrated within migrant populations often because of a higher disease burden in the migrant's country of origin. National programmes consequently focus on screening and treating LTBI in migrants to prevent future tuberculosis cases; however, how effective these programmes are is unclear. We aimed to assess LTBI treatment initiation and outcomes among migrants, and the factors that influence both.

Methods

For this systematic review and meta-analysis, we searched Embase, MEDLINE, and Global Health, and manually searched grey literature from Jan 1, 2000, to April 21, 2020. We included primary research articles reporting on LTBI treatment initiation or completion, or both, in migrants and excluded articles in which data were not stratified by migrant status, or in which the data were related to outcomes before 2000. There were no geographical or language restrictions. All included studies were quality appraised using recognised tools depending on their design, and we assessed the heterogeneity of analyses using I². We extracted data on the numbers of migrants initiating and completing treatment. Our primary outcomes were LTBI treatment initiation and completion in migrants (defined as foreign-born). We used random-effects meta-regression to examine the influence of factors related to these outcomes. The study is registered with PROSPERO (CRD42019140338).

Findings

2199 publications were retrieved screened, after which 39 publications from 13 mostly high-income, low-burden countries were included in our analyses, with treatment initiation and completion data reported for 31 598 migrants positive for LTBI, with not all articles reporting the full pathway from initiation to completion. The pooled estimate for the true proportion of migrants testing positive who initiated treatment was 69% (95% CI 51–84; I²= 99·62%; 4409 of 8764). The pooled estimate for the true proportion of migrants on treatment in datasets, who subsequently completed it was 74% (95% CI = 66–81; I²= 99·19%; 15 516 of 25 629). Where data were provided for the entire treatment pathway, the pooled estimate for the true proportion of migrants who initiated and completed treatment after a positive test was only 52% (95% CI 40–64; I²= 98·90%; 3289 of 6652). Meta-regression showed that LTBI programmes are improving, with more recent reported data (2010–20) associated with better rates of treatment initiation and completion, with multiple complex factors affecting treatment outcomes in migrants.

Interpretation

Although our analysis highlights that LTBI treatment initiation and completion in migrants has improved considerably from 2010–20, there is still room for improvement, with drop out reported along the entire treatment pathway. The delivery of these screening and treatment programmes will require further strengthening if the targets to eradicate tuberculosis in low-incidence countries are to be met, with greater focus needed on engaging migrants more effectively in the clinic and understanding the diverse and unique barriers and facilitators to migrants initiating and completing treatment.

Funding

European Society of Clinical Microbiology and Infectious Diseases, the Rosetrees Trust, the National Institute for Health Research, and the Academy of Medical Sciences.

The implementation of rifapentine and isoniazid (3HP) in two remote Arctic communities with a predominantly Inuit population, the Taima TB 3HP study

Background: The incidence of TB among Inuit is the highest in Canada. A significantly shorter latent TB infection (LTBI) treatment with rifapentine and isoniazid once weekly for 12 weeks (3HP) is now available in limited settings in Canada.Methods: A prospective open-label 2-year observational postmarketing study was conducted introducing 3HP for the first time in Canada in Iqaluit followed by a program rollout in Qikiqtarjuaq, Nunavut.Results: A total of 247 people were offered 3HP, 102 in the Iqaluit postmarketing study and 145 in the Qikiqtarjuaq program roll out. Although statistical significance was not reached, more people who started treatment completed treatment in the 3HP group (Iqaluit, 60/73 (82.2%) and Qikiqtarjuaq, 89/115 (77.4%)) than in the historical control 9INHgroup (306/420 = 72.9%) (p = 0.2). Most of the adverse events in 3HP treated patients were associated with mild discomfort but no disruption of normal daily activity. Not drinking alcohol was associated with increased 3HP completion (OR 13.33, 95% CI, 2.27-78.20) as was not taking concomitant medications (OR 7.19, 95% CI, 1.47-35.30).Conclusions: The present study supports the feasibility and safety profile of 3HP for the treatment of LTBI in Nunavut.

An open label, randomised controlled trial of rifapentine versus rifampicin based short course regimens for the treatment of latent tuberculosis in England: the HALT LTBI pilot study

BACKGROUND

Ending the global tuberculosis (TB) epidemic requires a focus on treating individuals with latent TB infection (LTBI) to prevent future cases. Promising trials of shorter regimens have shown them to be effective as preventative TB treatment, however there is a paucity of data on self-administered treatment completion rates. This pilot trial assessed treatment completion, adherence, safety and the feasibility of treating LTBI in the UK using a weekly rifapentine and isoniazid regimen versus daily rifampicin and isoniazid, both self-administered for 12 weeks.

METHODS

An open label, randomised, multi-site pilot trial was conducted in London, UK, between March 2015 and January 2017. Adults between 16 and 65 years with LTBI at two TB clinics who were eligible for and agreed to preventative therapy were consented and randomised 1:1 to receive either a weekly combination of rifapentine/isoniazid ('intervention') or a daily combination of rifampicin/isoniazid ('standard'), with both regimens taken for twelve weeks; treatment was self-administered in both arms. The primary outcome, completion of treatment, was self-reported, defined as taking more than 90% of prescribed doses and corroborated by pill counts and urine testing. Adverse events were recorded.

RESULTS

Fifty-two patients were successfully enrolled. In the intervention arm 21 of 27 patients completed treatment (77.8, 95% confidence interval [CI] 57.7-91.4), compared with 19 of 25 (76.0%, CI 54.9-90.6) in the standard of care arm. There was a similar adverse effect profile between the two arms.

CONCLUSION

In this pilot trial, treatment completion was comparable between the weekly rifapentine/isoniazid and the daily rifampicin/isoniazid regimens. Additionally, the adverse event profile was similar between the two arms. We conclude that it is safe and feasible to undertake a fully powered trial to determine whether self-administered weekly treatment is superior/non-inferior compared to current treatment.

TRIAL REGISTRATION

The trial was funded by the NIHR, UK and registered with ISRCTN ( 26/02/2013-No.04379941 ).

[Factors associated with completion of isoniazid preventive therapy in children in Quito, Ecuador (2014-2016 and 2018)Fatores associados à adesão à terapia preventiva com isoniazida em crianças de Quito, Equador (2014-2016 e 2018)]

OBJECTIVE

Determine the percentage of children under 5 years of age who completed isoniazid preventive therapy (IPT) in health facilities in Quito, Ecuador, and assess related factors.

METHODS

Operations research with cohort design. Data were obtained from treatment reports on children in IPT between 2014 and 2016, and from ad hoc surveys of caregivers of children who received IPT in 2018.

RESULTS

Children under 5 represented 29.3% of all contacts of index cases; 73% completed IPT and 88.9% had at least six months of therapy. Associations were found with the bacterial load of the index case, with living in a given district, and with the year in which treatment was initiated. Surveys were conducted with nine staff members of health facilities and nine caregivers of children; diverse responses were given regarding the causative agent of tuberculosis, its transmission, and the characteristics of preventive therapy.

CONCLUSIONS

The majority of children under 5 years of age who initiated IPT completed at least 80% of the prescribed doses, with varying associations and knowledge on the part of their caregivers. In this context, there is a need for further operations research in order to learn more about adherence and about the knowledge, attitudes, and practices of health professionals and those affected by tuberculosis, and their environment.

Ambulatory independence is associated with higher incidence of latent tuberculosis infection in long-term care facilities in Taiwan

BACKGROUND/PURPOSE

Tuberculosis (TB) in the elderly population remains a major challenge in areas with intermediate disease burden like Taiwan. Despite the increasing burden and high risks of TB in the elderly population, particularly those living in long-term care facilities (LTCFs), diagnostic testing for latent tuberculosis infection (LTBI) has not been carefully evaluated in this group. This study aimed to investigate the prevalence and predictors of LTBI in older adults living in LTCFs.

METHODS

Older adults living in seven LTCFs in Taiwan were prospectively enrolled between January and July 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-tube was used to determine presence of LTBI. Predictors for LTBI were analyzed.

RESULTS

A total of 258 participants were enrolled, including 240 older residents (mean age, 81.6 years; male, 51.2%) and 18 employees (mean age, 64.8 years; male, 22.2%). The proportion of independent status in ambulation assessments significantly declined with aging (p < 0.001). The IGRA-positivity rate in LTCFs was 31.4% (81/258), which consisted of 73 (30.4%) residents and 8 (44.4%) employees. The IGRA results were different with respect to the ambulation status (p = 0.052). In the multivariate logistic regression analysis, the only independent predictor of LTBI among older adults in LTCFs was independent ambulation (odds ratio, 2.16; 95% confidence interval, 1.09-4.28; p = 0.027).

CONCLUSIONS

There was a high prevalence of LTBI among older adults in LTCFs in Taiwan. Independent ambulation was the only independent predictor of LTBI.

Latent tuberculosis screening and treatment among asylum seekers: a mixed-methods study

Introduction

Evidence on conditions for implementation of latent tuberculosis infection (LTBI) screening and treatment among asylum seekers is needed to inform tuberculosis (TB) control policies. We used mixed-methods to evaluate the implementation of an LTBI screening and treatment programme among asylum seekers in the Netherlands.

Methods

We offered voluntary LTBI screening to asylum seekers aged ≥12 years living in asylum seeker centres from countries with a TB incidence >200 per 10 000 population. We calculated LTBI screening and treatment cascade coverage, and assessed associated factors with Poisson regression using robust variance estimators. We interviewed TB care staff (seven group interviews) and Eritrean clients (21 group and 21 individual interviews) to identify programme enhancers and barriers.

Results

We screened 719 (63% of 1136) clients for LTBI. LTBI was diagnosed among 178 (25%) clients; 149 (84%) initiated LTBI treatment, of whom 129 (87%) completed treatment. In-person TB and LTBI education, the use of professional interpreters, and collaboration with partner organisations were enhancers for LTBI screening uptake. Demand-driven LTBI treatment support by TB nurses enhanced treatment completion. Factors complicating LTBI screening and treatment were having to travel to public health services, language barriers and moving from asylum seeker centres to the community during treatment.

Conclusion

LTBI screening and treatment of asylum seekers is feasible and effective when high quality of care is provided, including culture-sensitive TB education throughout the care cascade. Additionally, collaboration with partner organisations, such as agencies responsible for reception and support of asylum seekers, should be in place.

Immigrant screening for latent tuberculosis infection: numbers needed to test and treat, a Norwegian population-based cohort study

OBJECTIVES

To estimate the number needed to screen (NNS) and the number needed to treat (NNT) to prevent one tuberculosis (TB) case in the Norwegian immigrant latent tuberculosis infection (LTBI) screening programme and to explore the effect of delay of LTBI treatment initiation.

DESIGN

Population-based, prospective cohort study.

PARTICIPANTS

Immigrants to Norway.

OUTCOME

Incident TB.

METHODS

We obtained aggregated data on immigration to Norway in 2008-2011 and used data from the Norwegian Surveillance System for Infectious Diseases to assess the number of TB cases arising in this cohort within 5 years after arrival. We calculated the average NNS and NNT for immigrants from the top 10 source countries for TB in Norway and by estimated TB incidence rates in source countries. We explored the sensitivity of these estimates with regard to test performance, treatment efficacy and treatment adherence using an extreme value approach, and assessed the effects of emigration, time to TB diagnosis (to define incident TB) and intervention timing.

RESULTS

NNS and NNT were overall high, with substantial variation. NNT showed numerically stronger negative correlation with TB notification rate in Norway (-0.75 [95% CI -1.00 to -0.44]) than with the WHO incidence rate (IR) (-0.32 [95% CI -0.93 to 0.29]). NNT was affected substantially by emigration and the definition of incident TB. Estimates were lowest for Somali (NNS 99 [70-150], NNT 27 [19-41]) and highest for Thai immigrants (NNS 585 [413-887], NNT 111 [79-116]). Implementing LTBI treatment in immigrants sooner after arrival may improve the effectiveness of the programme.

CONCLUSION

Using TB notifications in Norway, rather than IR in source countries, would improve targeting of immigrants for LTBI management. However, the overall high NNT is a concern and challenges the scale-up of preventive LTBI treatment for significant public health impact. Better data are urgently needed to monitor and evaluate NNS and NNT in countries implementing LTBI screening.

Screening and Treatment of Latent Tuberculosis Infection among Healthcare Workers at a Referral Hospital in Korea

Background

Healthcare workers (HCWs) have a high risk of tuberculosis (TB) infection. Since August 2017, Korea has mandated the testing of latent TB infection (LTBI) and recommended treatment from HCWs at medical institutions. However, the acceptance/completion rate and adverse events of LTBI treatment have not been analyzed.

Materials and Methods

From February to August 2017, we conducted a retrospective study at a referral university hospital in Korea, to screen the interferon-gamma release assay (IGRA) tests conducted for all HCWs for detecting and treating LTBI. HCWs diagnosed with LTBI were offered a 9-month isoniazid (9H), 3-month isoniazid/rifampin (3HR), or 4-month rifampin regimen. We investigated the acceptance/completion rate, adverse events, and causes of discontinuation or change in LTBI medication. A major adverse event was one wherein a patient had any adverse event ≥grade 3 causing LTBI treatment interruption.

Results

Of the 1,538 HCWs, 1,379 underwent IGRA testing for LTBI. Among them, 13.6% (187/1,379) tested positive and 73.3% (137/187) received treatment. The overall completion rate was 97.8% (134/137). HCWs were significantly more likely to complete first-line therapy with 3HR than with 9H (91.4% vs. 76.7%, P = 0.02). The most common major adverse event was hepatotoxicity (n = 7), followed by thrombocytopenia (n = 1) and anaphylactic shock (n = 1). Hepatotoxicity and hepatotoxicity (≥ grade 2) were more frequent in 9H than in 3HR (39.5% vs. 17.2%, P = 0.006 and 18.6% vs. 3.7%, P = 0.005, respectively). The median time to hepatotoxicity was 96 days (interquartile range, 20 – 103 days).

Conclusion

Completion of first-line therapy for LTBI is more likely with 3HR than with 9H. This might be related to the development of hepatotoxicity after around 3 months of treatment. Anaphylactic shock and platelet count should be carefully monitored in those receiving rifampin-containing regimens.