Tuberculosis-related stigma leading to an incomplete contact investigation in a low-incidence country

Tuberculosis in elderly Australians: a 10-year retrospective review

Objective

This report describes the epidemiology of active tuberculosis (TB) in elderly Australians (≥ 65 years) with analysis of the factors associated with TB disease and successful treatment outcomes.

Methods

A retrospective study of TB cases reported to the National Notifiable Diseases Surveillance System over a 10-year period from 2011 to 2020 was conducted. Cases were stratified by sex, age, risk factors, drug resistance, treatment type and outcome. Notification rates and incidence rate ratios with 95% confidence intervals were calculated and factors associated with treatment success analysed using multivariable logistic regression.

Results

A total of 2231 TB cases among elderly people were reported over the study period, with a 10-year mean incidence rate of 6.2 per 100 000 population. The median age of cases was 75 years (range 65-100 years); most were male (65%) and born overseas (85%). Multivariable analysis found that successful treatment outcome was strongly associated with younger age, while unsuccessful treatment outcome was associated with being diagnosed within the first 2 years of arrival in Australia, ever having resided in an aged-care facility and resistance to fluoroquinolones.

Discussion

Compared to other low-incidence settings in the Western Pacific Region, TB incidence in elderly people is low and stable in Australia, with most cases occurring among recent migrants from TB-endemic settings. Continued efforts to reduce TB importation and address migrant health, especially among elderly people, are important.

How We Treat Drug-Susceptible Pulmonary Tuberculosis: A Practical Guide for Clinicians

Tuberculosis (TB) remains one of the leading causes of morbidity and mortality worldwide and pulmonary TB (PTB) is the main variant responsible for fueling transmission of the infection. Effective treatment of drug-susceptible (DS) TB is crucial to avoid the emergence of Mycobacterium tuberculosis-resistant strains. In this narrative review, through a fictional suggestive case of DS PTB, we guide the reader in a step-by-step commentary to provide an updated review of current evidence in the management of TB, from diagnosis to post-treatment follow-up. World Health Organization and Centre for Diseases Control (CDC) guidelines for TB, as well as the updated literature, were used to support this manuscript.

Exploring stakeholders perspectives on TB contact investigation in Cali, Colombia: a qualitative study

Introduction

Contact investigation is a proven intervention for tuberculosis (TB) case finding and prevention. Although widely endorsed by national public health authorities and the World Health Organization, many countries struggle to implement it effectively. The objective of the study is to describe and characterize the barriers and facilitators of TB contact investigation in Cali, Colombia from the perspective and experience of the key stakeholders involved.

Methods

We collected data from group discussions during two workshop sessions with clinic and public health staff involved in TB contact investigation (June 2019 and March 2020 respectively) and semi-structured interviews with TB cases and their household contacts (July 2019 to April 2020). We undertook an inductive thematic analysis with the RADaR technique to characterize the barriers and facilitators of the TB contact investigation process.

Results

The two workshops included 21 clinics and 12 public health staff. We also conducted 26 semi-structured interviews with TB cases and their household contacts. Using thematic analysis, we identified four common themes: Healthcare Operations, Essential Knowledge, Time Limitations and Competing Responsibilities, and Interpersonal Interactions. The main barriers to conducting household visits were low data quality, stigma and mistrust, safety concerns for health workers, and limited resources. The main barriers to TB uptake by contacts were competing responsibilities, low TB risk perceptions among contacts, and difficulty accessing diagnostic tests for contacts. In contrast, good communication and social skills among health workers and accurate TB knowledge facilitated successful household visits and TB test uptake, according to key stakeholders.

Conclusion

This study provides a deeper understanding of TB contact investigation barriers and facilitators in a high-prevalence urban setting in a middle-income country from the perspective and experience of key stakeholders. The study shed light on the barriers that hinder household contacts engagement and TB test uptake such as issues of systemic capacity and TB knowledge. Also, highlighted facilitators such as the importance of interpersonal communication skills among health workers in the public and private sector. The insights from this study can serve as a valuable resource for public health organizations seeking to enhance their contact investigation efforts and improve TB control in similar settings.

Tuberculosis related barriers and facilitators among immigrants in Atlantic Canada: A qualitative study

Tuberculosis (TB) is a disease caused by the bacterium Mycobacterium tuberculosis and affects approximately one-quarter of the world's population. Immigrant populations in Canada are disproportionately affected by TB. Canada's immigration medical examinations include screening for active TB but not latent TB infection (LTBI). In LTBI, the bacterium remains dormant within the host but can reactivate and cause disease. Once active, TB can be transmitted to close contacts sharing confined spaces leading to the possibility of outbreaks in the broader community. This study aimed to 1) assess the current TB knowledge, perceived risk, and risk behaviors of immigrants in Atlantic Canada as well as 2) identify barriers and facilitators to testing and treatment of TB among this population. Three focus group discussions were conducted with a total of 14 non-Canadian born residents of New Brunswick aged 19 years and older. Data were analyzed using inductive thematic analysis. Four themes were identified from the data relating to barriers to testing and treatment of LTBI: 1) Need for education, 2) stigma, 3) fear of testing, treatment, and healthcare system, and 4) complacency. Results included reasons individuals would not receive TB testing, treatment, or seek help, as well as facilitators to testing and treatment. These findings may inform the implemention of an LTBI screening program in Atlantic Canada and more broadly across the country.

Contact Tracing: Barriers and Facilitators

Contact tracing-the process of identifying, isolating, and managing infected persons and their contacts-is a recognized public health measure for controlling the transmission of infectious diseases. In the context of the COVID-19 pandemic, contact tracing has received intense attention. We provide a brief overview of the history of contact tracing during several major disease outbreaks in the past century: syphilis and other sexually transmitted infections, HIV infection, tuberculosis, Ebola virus disease, and COVID-19. Our discussion on the barriers to and facilitators of contact tracing offers a perspective on societal and institutional roles and dynamics, stigma as a major barrier to effective tracing efforts, and how the nature and epidemiology of the infection itself can affect its success. We explore the evolution and adaptation of contact tracing and provide insights for future programming and research. (Am J Public Health. Published online ahead of print June 2, 2022: e1-e9. https://doi.org/10.2105/AJPH.2022.306842).

Social Stigma Related to COVID-19 Disease Described by Primary and Secondary School Teachers and Adolescents Living With HIV in Western Kenya

Introduction: Understanding community members' knowledge, attitudes, and beliefs about the novel SARS-CoV-2 virus and the prevalence of associated stigma are critical steps for increasing accurate public health knowledge, encouraging uptake of preventative or mitigating health behaviors, and ultimately bringing the COVID-19 pandemic under control.

Methods: We conducted a one-time, phone-based assessment to assess the presence of perceived COVID-19 community stigma reported by Kenyan primary and secondary school teachers, as well as adolescents living with HIV. Participants were previously enrolled in an ongoing, cluster-randomized trial to evaluate the impact of multi-media teacher training on teachers' negative attitudes and beliefs around HIV. The SAFI Stigma Questionnaire, a validated tool to assess HIV-related stigma in this setting, was adapted to ask questions regarding the stigma and discrimination experienced or perceived during the COVID-19 pandemic.

Results: We enrolled 330 participants in this study, including 311 primary and secondary teachers (56% female, average age 36 years) and 19 adolescents living with HIV (57.89% female, average age 16.37 years). None of the adolescent participants reported witnessing or experiencing discrimination related to COVID-19, nor did they report losing financial and/or social support. In contrast, the teacher participants reported prominent social stigma experiences of various levels and related to COVID-19. Teachers in the intervention group, who had completed the multi-media training on HIV-related stigma, were significantly less likely to think that the community viewed COVID-19 as a dirty or shameful disease, and less likely to feel it was important to keep their COVID-19 infection a secret, compared to the teacher control group.

Conclusion: These findings suggest that COVID-19-related stigma may be prevalent in western Kenya and that interventions to reduce community-level stigma for HIV may also have a protective impact on other stigmatized infectious diseases such as COVID-19.

Race, Ethnicity, Nativity and Perceptions of Health Risk during the COVID-19 Pandemic in the US

Previous research demonstrates that pandemics, including COVID-19, have disproportionate effects on communities of color, further exacerbating existing healthcare inequities. While increasing evidence points to the greater threat posed by COVID-19 to Latinx communities, less remains known about how identification as Latinx and migration status influence their perception of risk and harm. In this article, we use cross-sectional data from a large national probability sample to demonstrate a large positive association between ethnic identity and migration status and perceptions of harm from COVID-19 in the US. We find that individuals identifying as Hispanic/Latinx and first-generation immigrants report significantly greater risks of becoming infected by COVID-19 in the next three months, and dying from the virus if they do contract it. Further, subgroup analysis reveals that health risks are especially felt by individuals of Mexican descent, who represent the largest share of US Latinxs. Collectively, our results provide evidence about how the pandemic places increased stress on people from Latinx and immigrant communities relative to White non-Hispanic individuals in the US.

Implementation of a volunteer contact tracing program for COVID-19 in the United States: A qualitative focus group study

Background

Contact tracing is an important tool for suppressing COVID-19 but has been difficult to adapt to the conditions of a public health emergency. This study explored the experiences and perspectives of volunteer contact tracers in order to identify facilitators, challenges, and novel solutions for implementing COVID-19 contact tracing.

Methods

As part of a study to evaluate an emergently established volunteer contact tracing program for COVID-19 in New Haven, Connecticut, April-June 2020, we conducted focus groups with 36 volunteer contact tracers, thematically analyzed the data, and synthesized the findings using the RE-AIM implementation framework.

Results

To successfully reach cases and contacts, participants recommended identifying clients’ outreach preferences, engaging clients authentically, and addressing sources of mistrust. Participants felt that the effectiveness of successful isolation and quarantine was contingent on minimizing delays in reaching clients and on systematically assessing and addressing their nutritional, financial, and housing needs. They felt that successful adoption of a volunteer-driven contact tracing model depended on the ability to recruit self-motivated contact tracers and provide rapid training and consistent, supportive supervision. Participants noted that implementation could be enhanced with better management tools, such as more engaging interview scripts, user-friendly data management software, and protocols for special situations and populations. They also emphasized the value of coordinating outreach efforts with other involved providers and agencies. Finally, they believed that long-term maintenance of a volunteer-driven program requires monetary or educational incentives to sustain participation.

Conclusions

This is one of the first studies to qualitatively examine implementation of a volunteer-run COVID-19 contact tracing program. Participants identified facilitators, barriers, and potential solutions for improving implementation of COVID-19 contact tracing in this context. These included standardized communication skills training, supportive supervision, and peer networking to improve implementation, as well as greater cooperation with outside agencies, flexible scheduling, and volunteer incentives to promote sustainability.

Tuberculosis-related stigma and its determinants in Dalian, Northeast China: a cross-sectional study

Background

The stigma of tuberculosis (TB) poses a significant challenge to TB control because it leads to delayed diagnosis and non-adherence. However, few studies on TB-related stigma have been completed in China. The aim of the current study was to explore the status of TB-related stigma and its associated predictive factors among TB patients in Dalian, Northeast China.

Methods

An institution-based, cross-sectional survey was conducted among outpatients at Dalian Tuberculosis Hospital in Liaoning Province, Northeast China. Data were collected by using a questionnaire that measured TB-related stigma, treatment status, anxiety, social support, doctor-patient communication and so on. A multiple linear regression model was used to determine the predictors of TB-related stigma.

Results

A total of 601 eligible participants were recruited. The mean score for TB-related stigma was 9.07, and the median score was 10. The average scores for anxiety, social support and doctor-patient communication were 4.03, 25.41 and 17.17, respectively. Multiple linear regression analysis revealed that patients who were female (β = 1.19, 95% CI: 0.38–2.01, P < 0.05), had self-assessed moderate or severe disease (β = 1.08, 95% CI: 0.12–2.03 and β = 1.36, 95% CI: 0.03–2.70, respectively, P < 0.05), and had anxiety (β = 0.38, 95% CI: 0.30–0.46, P < 0.001) were more likely to have a greater level of TB-related stigma than their counterparts. However, a significantly lower level of TB-related stigma was observed in patients with good social support (β = − 0.25, 95% CI: − 0.33--0.17, P < 0.001) and doctor-patient communication (β = − 0.14, 95% CI: − 0.29--0.00, P < 0.05).

Conclusions

This study showed that stigma among TB patients was high. Targeted attention should be paid to female patients and patients with moderate or severe disease in TB stigma-related interventions. Moreover, the important role of social support and doctor-patient communication in reducing TB-related stigma should also be emphasized.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-10055-2.

Constructing and Communicating COVID-19 Stigma on Twitter: A Content Analysis of Tweets during the Early Stage of the COVID-19 Outbreak

This study focuses on stigma communication about COVID-19 on Twitter in the early stage of the outbreak, given the lack of information and rapid global expansion of new cases during this period. Guided by the model of stigma communication, we examine four types of message content, namely mark, group labeling, responsibility, and peril, that are instrumental in forming stigma beliefs and sharing stigma messages. We also explore whether the presence of misinformation and conspiracy theories in COVID-19-related tweets is associated with the presence of COVID-19 stigma content. A total of 155,353 unique COVID-19-related tweets posted between December 31, 2019, and March 13, 2020, were identified, from which 7000 tweets were randomly selected for manual coding. Results showed that the peril of COVID-19 was mentioned the most often, followed by mark, responsibility, and group labeling content. Tweets with conspiracy theories were more likely to include group labeling and responsibility information, but less likely to mention COVID-19 peril. Public health agencies should be aware of the unintentional stigmatization of COVID-19 in public health messages and the urgency to engage and educate the public about the facts of COVID-19.

Factors associated with household contacts' tuberculosis testing and evaluation

PURPOSE

No research has been done in New York City that shows the demographic characteristics of household contacts testing, evaluation, and treatment of LTBI. The objective of the study was to identify demographic factors associated with household contacts' TB testing, evaluation, and LTBI treatment.

DESIGN AND METHODS

A retrospective analysis of the New York City (NYC) TB registry data that examined the factors (gender, age, country of birth, race/ethnicity, and borough of residence) associated with TB testing, evaluation, and LTBI treatment. The study sample included all household contacts of TB cases identified from 2010 to 2014 (N = 3,008). The data set was chosen when nurses were the primary case managers at chest centers in the department of health. Descriptive and inferential analysis was used to identify factors associated with testing, evaluation, and LTBI treatment.

RESULTS

The demographic characteristics of household contacts associated with testing, evaluation, and LTBI treatment were consistent with those of TB cases in NYC from 2010 to 2014. Those not tested, not fully evaluated, and refusing LTBI treatment were most often aged 18-44 years and were non-US born. Males were significantly more likely than females not to be fully evaluated. Among racial/ethnic groups, Asian and Hispanic persons were at higher risk of not being fully evaluated, and residents of Queens had the highest risk among the five boroughs. In multivariate analyses, age was a significant predictor of behavior, such that the older the person the less likely to get TB testing or to accept LTBI treatment. Non-US country of birth was associated with lower likelihood of being fully evaluated but more likely to accept LTBI treatment when fully evaluated, while Asian or Hispanic race/ethnicity was associated with higher likelihood of both behaviors.

CONCLUSIONS

Findings on age from this study will enable public health agencies and public health nurses to plan for effective strategies that will increase the number of household contacts who accept TB testing and evaluation, as well as the numbers who will accept and complete LTBI treatment.

Addressing Disease-Related Stigma During Infectious Disease Outbreaks

Outbreaks of emerging infectious disease are a constant threat. In the last 10 years, there have been outbreaks of 2009 influenza A (H1N1), Ebola virus disease, and Zika virus. Stigma associated with infectious disease can be a barrier to adopting healthy behaviors, leading to more severe health problems, ongoing disease transmission, and difficulty controlling infectious disease outbreaks. Much has been learned about infectious disease and stigma in the context of nearly 4 decades of the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome pandemic. In this paper, we define stigma, discuss its relevance to infectious disease outbreaks, including how individuals and communities can be affected. Adapting lessons learned from the rich literature on HIV-related stigma, we propose a strategy for reducing stigma during infectious disease outbreaks such as Ebola virus disease and Zika virus. The implementation of brief, practical strategies such as the ones proposed here might help reduce stigma and facilitate more effective control of emerging infectious diseases.

Perceptions of Tuberculosis Among Individuals Born in a High-Endemic Setting, Now Living in a Low-Endemic Setting

Of all individuals diagnosed with tuberculosis (TB) in Sweden 2015 were 90% born in other countries. Early diagnosis and treatment is essential to avoid TB transmission. Lack of knowledge about TB and anticipated negative social consequences have proved to be significant contributing factors to delay in seeking health care. This study aimed to understand the perception of TB among people originating from a high-endemic region, currently living in a low-endemic region. A qualitative study design, with male and female participants from a high-endemic region divided into focus groups. A semi-structured interview guide was used to elicit their perceptions of TB. A qualitative content analysis was performed on the recorded material from the interviews. The informants noted that their attitude towards individuals with TB had changed, previously they had felt prejudiced towards them whereas now they felt supportive. It seems possible to diminish TB stigma by ensuring suitable health care is available in combination with correct information about transmission, infectiousness and treatment.

High rate of transmission in a pulmonary tuberculosis outbreak in a primary school, north-eastern Italy, 2019

Italy is a low-incidence country for tuberculosis (TB). We describe a TB outbreak in a primary school in north-eastern Italy, involving 10 cases of active pulmonary disease and 42 cases of latent infection. The index case was detected in March 2019, while the primary case, an Italian-born schoolteacher, was likely infectious since January 2018. Administration of a pre-employment health questionnaire to school staff with sustained contact with children should be considered in low-incidence countries.

Stigma against tuberculosis may hinder non-household contact investigation: a qualitative study in Thailand

Setting

A northern province in Thailand.

Objectives

To explore experiences and perspectives on tuberculosis (TB) contact investigations in non-household contacts.

Design

Focus group discussions and in-depth interviews with eight groups: three groups of former TB patients (teachers, students and hospital staff) and five groups of representatives from congregate settings such as schools and workplaces. Data were analysed using the modified grounded theory.

Result

Annual health check-ups at the workplace contributed to the early detection of active TB in teachers. Former TB patients were highly exposed to non-household contacts, but contact investigations were limited to household contacts only. Barriers and facilitators for non-household contact investigations are associated with five factors, including information, awareness and knowledge about TB; stigma; empathy; health system response and informing non-household contacts about TB exposure. Stigma may be the main barrier to investigations among non-household contacts because TB patients tend to withhold information about their diagnosis from colleagues. Lack of knowledge and misperceptions regarding TB transmission contributed to stigma. Empathy with other people encouraged TB patients to inform non-household contacts.

Conclusion

Non-household contact investigations are not performed despite the risk of TB transmission. To promote contact investigations in congregate settings, interventions to overcome TB stigma and improve public knowledge about TB transmission are required.

Genetic Diversity of Mycobacterium tuberculosis Isolates in the Metropolitan Area of Rome

BACKGROUND

The presence in a geographic area of Mycobacterium tuberculosis (Mtb) strains belonging to different phylogeographic lineages and showing different drug susceptibility patterns may suggest recent transmission, with implications in terms of patient clinical management and disease control. The aim of this study was to carry out a preliminary epidemiological investigation of tuberculosis (TB) cases in Rome.

METHODS

A total of 232 Mtb isolates, collected from new or previously treated patients, admitted between 2008 and 2014 at 2 hospital settings in Rome with a diagnosis of TB, were analyzed by spoligotyping and analyzing 24 variable-number tandem repeats (VNTR) mycobacterial interspersed repetitive-unit (MIRU) loci. The SITVIT2 database and the MIRU-VNTRplus web applications were used to identify the strain genotypes and to generate phylogenetic trees.

RESULTS

Based on the position on the phylogenetic tree, 97.4% of the strains were associated with 1 of the 7 main lineages. The Euro-American lineage was the most commonly represented (81.9%) within both Italian and foreign-born populations, although all main lineages were present. The highest frequency of drug-resistant strains was found among the East-Asian lineage (Beijing genotype) isolated from foreign-born patients.

CONCLUSIONS

Dynamics of TB transmission in Rome indicate recent spread of Mtb strains belonging to phylogeographic lineages and clades usually found in countries and geographic areas with a high incidence of TB, similarly to what is observed in most metropolitan areas in Western Europe. Knowledge from molecular and classical epidemiology provides an important tool for disease control.

SIGNIFICADOS DAS EXPERIÊNCIAS CORPORAIS DE PESSOAS COM TUBERCULOSE PULMONAR: A CONSTRUÇÃO DE UMA NOVA IDENTIDADE

RESUMO Objetivo: compreender os significados das experiências corporais de pessoas em tratamento para tuberculose pulmonar. Método: pesquisa qualitativa, realizada no município de Pelotas, Estado do Rio Grande do Sul, Brasil. Utilizou-se o referencial teórico da Antropologia em Saúde de Byron Good. Foram realizadas entrevistas semiestruturadas com dez pessoas na segunda fase de tratamento para a tuberculose, em seus domicílios, entre abril e maio de 2015. Para a análise dos dados empregou-se a técnica de Análise de Conteúdo Temática. Resultados: apreenderam-se duas categorias: O corpo sinalizador da doença que se revela na presença de sintomas (febre, emagrecimento, fraqueza) e O corpo doente que manifesta sofrimento, temor, estigma e afastamento. Conclusão: a presença da tuberculose no corpo é capaz de gerar apreensão, rompimento das atividades de lazer e trabalho, afastamento do convívio familiar e social. É essencial desenvolver um olhar para o cuidado, compreender as necessidades singulares de quem vive o adoecimento, valorizar a sua história de vida e a sua subjetividade.

A highly transmissible tuberculosis outbreak: the importance of bars

The transmission of tuberculosis (TB) in bars is difficult to study. The objective was to describe a large TB outbreak in a company's bar and other leisure settings. A descriptive study of a TB outbreak was carried out. Contacts were studied in the index case's workplace bar (five circles of contacts) and other recreational areas (social network of three bars in the index case's neighbourhood). Chest X-rays were recommended to contacts with positive tuberculin skin tests (TST) (⩾5 mm). The risk of latent tuberculosis infection (LTBI) was determined using an adjusted odds ratio. The dose-response relationship was determined using the chi-square test for linear trend. We studied 316 contacts at the index case's workplace and detected five new cases of TB. The prevalence of LTBI was 57·9% (183/316) and was higher in the first circle, 96·0% (24/25), and lower in the fifth, 46·5% (20/43) (P < 0·0001). Among 58 contacts in the three neighbourhood bars, two TB cases were detected and the LTBI prevalence was 51·7% (30/58). Two children of one secondary TB company patient became ill. Bars may be transmission locations for TB and, as they are popular venues for social events, should be considered as potential areas of exposure.

Stakeholder perspectives for optimization of tuberculosis contact investigation in a high-burden setting

Introduction

Optimal tuberculosis contact investigation impacts TB prevention, timely case finding and linkage to care, however data on routine implementation in high burden contexts is limited.

Materials and methods

In a multi-method qualitative study based on individual interviews with TB patients, facility observations and focus group discussions with health workers (HWs) in 13 public health facilities, and key informant interviews with governmental and non-governmental experts, we describe TB contact investigation in the context of an urban setting in Kenya and identify opportunities for optimization.

Results

Invitation of TB patients to bring close contacts by HWs was key for all patient decisions that led to contact screening in addition to patients’ understanding of TB transmission and desire to avoid contacts suffering from TB. Sub-optimal HW enquiry of TB patients and contacts presenting at the facility were missed opportunities which stemmed from lack of standardized operational procedures, documentation tools and HW training. Stakeholders proposed provision of fast tracked and holistic health packages for contacts seeking TB screening, and sustainable government led funding for the requisite infrastructure and workforce.

Conclusion

TB contact invitation by HWs leading to contact screening occurs in this context. Stakeholder perspectives inform the design of an operational framework for optimized delivery.

Interventions to improve contact tracing for tuberculosis in specific groups and in wider populations: an evidence synthesis

Background

The tracing and screening of people who have had contact with an active case of tuberculosis (TB) is an important element of TB control strategies.

Objectives

This study aimed to carry out a review of evidence regarding TB contact tracing, with a particular emphasis on research that was applicable to TB contact tracing in specific population groups in the UK.

Design

An evidence synthesis of literature of any study design on TB contact tracing in developed countries was carried out.

Setting

Any setting.

Population

Individuals found to have active TB disease, and people who have come into contact with them.

Interventions

Contact-tracing investigations.

Main outcome measures

Any outcome related to TB infection, contact investigations and/or the views of staff, people with TB disease, or their contacts.

Data sources

Searches for research published 1995 onwards were undertaken in the following databases: MEDLINE via Ovid SP, EMBASE via Ovid SP, EconLit via Ovid SP, PsycINFO via Ovid SP, Social Policy and Practice via Ovid SP, Cumulative Index to Nursing and Allied Health Literature via EBSCOhost, Science and Social Science Citation Indices via Web of Science and The Cochrane Library via Wiley Online Library.

Review methods

The study comprised a review of TB contact tracing in specific population groups and a review in wider populations. A narrative synthesis was completed and a logic model was developed from the literature.

Results

There were 112 articles in the review: 23 related to specific populations and 89 related to wider populations. The literature was of limited quality, with much general description of investigations. We identified only two (uncontrolled) studies that could be considered evaluative. Although the limitations of the evidence should be recognised, the review suggested the following: the value of a location-based approach, working with local communities and the media, partnership working, using molecular epidemiological testing, ensuring adequate systems and addressing fear of stigma. The literature on investigations for specific populations has much concordance with that reporting findings from wider population groups. The recognised limitations of conventional investigation methods may, however, be exacerbated in specific populations.

Limitations

The English-language inclusion criterion may have limited the breadth of countries represented. A meta-analysis was not possible owing to the nature of the literature. Relevant studies may have been missed by our searches, which used terminology relating to contact tracing rather than to active case finding or screening.

Conclusions

The review identified a sizeable volume of literature relating to contact investigations. However, it is currently predominantly descriptive, with little evaluative work underpinning investigations in either specific or wider populations. Our findings are, therefore, based on limited evidence. Further research is required if robust conclusions are to be made.

Future work

Research should further explore the development of measures that can be used to compare the effectiveness of different contact investigations, in studies using evaluative designs.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

First evaluation of QuantiFERON-TB Gold Plus performance in contact screening

Identifying latently infected individuals is crucial for the elimination of tuberculosis (TB). We evaluated for the first time the performance of a new type of interferon-γ release assay, QuantiFERON-TB Plus (QFT-Plus), which includes an additional antigen tube (TB2), stimulating both CD4+ and CD8+ T-cells in contacts of TB patients.

Contacts were screened for latent TB infection by tuberculin skin test, QFT-Plus and QuantiFERON-TB Gold in Tube (QFT-GIT).

In 119 TB contacts, the overall agreement between QFT-Plus and QFT-GIT was high, with a Cohen's κ of 0.8. Discordant results were found in 12 subjects with negative QFT-GIT and positive QFT-Plus results. In analyses of markers of TB exposure and test results, the average time spent with the index case was the strongest risk factor for positivity in each of these tests. The difference in interferon-γ production between the two antigen tubes (TB2−TB1) was used as an estimate of CD8+ stimulation provided by the TB2. TB2−TB1 values >0.6 IU·mL−1 were significantly associated with proximity to the index case and European origin.

QFT-Plus has a stronger association with surrogate measures of TB exposure than QFT-GIT in adults screened for latent TB infection. Interferon-γ response in the new antigen tube used an indirect estimate of specific CD8+ response correlates with increased Mycobacterium tuberculosis exposure, suggesting a possible role in identifying individuals with recent infection.