Tuberculosis infection control in resource-limited settings in the era of expanding HIV care and treatment

Direct estimates of absolute ventilation and estimated Mycobacterium tuberculosis transmission risk in clinics in South Africa

Healthcare facilities are important sites for the transmission of pathogens spread via bioaerosols, such as Mycobacterium tuberculosis. Natural ventilation can play an important role in reducing this transmission. We aimed to measure rates of natural ventilation in clinics in KwaZulu-Natal and Western Cape provinces, South Africa, then use these measurements to estimate Mycobacterium tuberculosis transmission risk. We measured ventilation in clinic spaces using a tracer-gas release method. In spaces where this was not possible, we estimated ventilation using data on indoor and outdoor carbon dioxide levels. Ventilation was measured i) under usual conditions and ii) with all windows and doors fully open. Under various assumptions about infectiousness and duration of exposure, measured absolute ventilation rates were related to risk of Mycobacterium tuberculosis transmission using the Wells-Riley Equation. In 2019, we obtained ventilation measurements in 33 clinical spaces in 10 clinics: 13 consultation rooms, 16 waiting areas and 4 other clinical spaces. Under usual conditions, the absolute ventilation rate was much higher in waiting rooms (median 1769 m3/hr, range 338-4815 m3/hr) than in consultation rooms (median 197 m3/hr, range 0-1451 m3/hr). When compared with usual conditions, fully opening existing doors and windows resulted in a median two-fold increase in ventilation. Using standard assumptions about infectiousness, we estimated that a health worker would have a 24.8% annual risk of becoming infected with Mycobacterium tuberculosis, and that a patient would have an 0.1% risk of becoming infected per visit. Opening existing doors and windows and rearranging patient pathways to preferentially use better ventilated clinic spaces result in important reductions in Mycobacterium tuberculosis transmission risk. However, unless combined with other tuberculosis infection prevention and control interventions, these changes are insufficient to reduce risk to health workers, and other highly exposed individuals, to acceptable levels.

Tuberculosis infection control practices and associated factors among healthcare workers in hospitals of Gamo Gofa Zone, Southern Ethiopia, institution-based cross-sectional study

Background

Tuberculosis infection control is a combination of measures designed to minimize the risk of tuberculosis transmission within populations. Healthcare workers are not sufficiently protected from tuberculosis infection in healthcare facilities where infection control protocols are not followed completely. Studies conducted in Ethiopia about tuberculosis infection control practices were self-report.

Objective

To assess tuberculosis infection control practices and associated factors among health care workers in hospitals of Gamo Gofa Zone, Southern Ethiopia.

Method

A facility-based cross-sectional study was conducted from March 6 to April 2, 2019. The sample size was 422. The sample was proportionally allocated to each hospital and the respective discipline. Simple random sampling was used to select participants from each discipline. Data were entered into EpiData version 4.4.2.1 and analyzed using SPSS Version 21 software. Multicollinearity and Model goodness-of-fit was checked. A multivariate logistic regression model at 95% CI was used to identify the predictors.

Result

The response rate was 97.4%. The proportion of good tuberculosis infection control practice was 39.9% [95% CI (35.5, 44.9)]. Knowledge on tuberculosis infection control measures [AOR = 3.65, 95% CI (2.07, 6.43)], educational level of degree and above [AOR = 2.78, 95% CI (1.7, 4.53)] and ever having tuberculosis-related training [AOR = 2.02, 95% CI (1.24, 3.31)] were significantly associated with good tuberculosis infection control practice.

Conclusion and recommendation

The proportion of good tuberculosis infection control practice among healthcare workers in hospitals of the Gamo Gofa Zone was 39.9%. The good practice of tuberculosis infection control was determined by educational level, working department, knowledge on tuberculosis infection control measures, and having tuberculosis-related training. Hence, training of healthcare workers, targeting diploma-holders in upgrading educational level programs, developing knowledge on tuberculosis infection control measures, and qualitative research to explore reasons for not practicing infection control measures is recommended.

Assessing tuberculosis control priorities in high-burden settings: a modelling approach

BACKGROUND

In the context of WHO's End TB strategy, there is a need to focus future control efforts on those interventions and innovations that would be most effective in accelerating declines in tuberculosis burden. Using a modelling approach to link the tuberculosis care cascade to transmission, we aimed to identify which improvements in the cascade would yield the greatest effect on incidence and mortality.

METHODS

We engaged with national tuberculosis programmes in three country settings (India, Kenya, and Moldova) as illustrative examples of settings with a large private sector (India), a high HIV burden (Kenya), and a high burden of multidrug resistance (Moldova). We collated WHO country burden estimates, routine surveillance data, and tuberculosis prevalence surveys from 2011 (for India) and 2016 (for Kenya). Linking the tuberculosis care cascade to tuberculosis transmission using a mathematical model with Bayesian melding in each setting, we examined which cascade shortfalls would have the greatest effect on incidence and mortality, and how the cascade could be used to monitor future control efforts.

FINDINGS

Modelling suggests that combined measures to strengthen the care cascade could reduce cumulative tuberculosis incidence by 38% (95% Bayesian credible intervals 27-43) in India, 31% (25-41) in Kenya, and 27% (17-41) in Moldova between 2018 and 2035. For both incidence and mortality, modelling suggests that the most important cascade losses are the proportion of patients visiting the private health-care sector in India, missed diagnosis in health-care settings in Kenya, and drug sensitivity testing in Moldova. In all settings, the most influential delay is the interval before a patient's first presentation for care. In future interventions, the proportion of individuals with tuberculosis who are on high-quality treatment could offer a more robust monitoring tool than routine notifications of tuberculosis.

INTERPRETATION

Linked to transmission, the care cascade can be valuable, not only for improving patient outcomes but also in identifying and monitoring programmatic priorities to reduce tuberculosis incidence and mortality.

FUNDING

US Agency for International Development, Stop TB Partnership, UK Medical Research Council, and Department for International Development.

Improving natural ventilation in hospital waiting and consulting rooms to reduce nosocomial tuberculosis transmission risk in a low resource setting

Background

TB transmission in healthcare facilities is an important public health problem, especially in the often-overcrowded settings of HIV treatment scale-up. The problem is compounded by the emergence of drug resistant TB. Natural ventilation is a low-cost environmental control measure for TB infection control where climate permits that is suited to many different areas in healthcare facilities. There are no published data on the effect of simple structural modifications to existing hospital infrastructure to improve natural ventilation and reduce the risk of nosocomial TB transmission.

The purpose of this study was to measure the effect of simple architectural modifications to existing hospital waiting and consulting rooms in a low resource setting on (a) improving natural ventilation and (b) reducing modelled TB transmission risk.

Methods

Room ventilation was measured pre- and post-modification using a carbon dioxide tracer-gas technique in four waiting rooms and two consulting rooms in two hospitals in Lima, Peru. Modifications included additional windows for cross-ventilation (n = 2 rooms); removing glass from unopenable windows (n = 2); creation of an open skylight (n = 1); re-building a waiting-room in the open air (n = 1). Changes in TB transmission risk for waiting patients, or healthcare workers in consulting rooms, were estimated using mathematical modelling.

Results

As a result of the infrastructure modifications, room ventilation in the four waiting rooms increased from mean 5.5 to 15; 11 to 16; 10 to 17; and 9 to 66 air-changes/hour respectively; and in the two consulting rooms from mean 3.6 to 17; and 2.7 to 12 air-changes/hour respectively. There was a median 72% reduction (inter-quartile range 51–82%) in calculated TB transmission risk for healthcare workers or waiting patients. The modifications cost <US$75 in four rooms, and US$1000 and US$7000 in the remaining two rooms.

Conclusions

Simple modifications to existing hospital infrastructure considerably increased natural ventilation, and greatly reduced modelled TB transmission risk at little cost.

Recurrent tuberculosis among HIV-coinfected patients: a case series from KwaZulu-Natal

Background

Recurrent tuberculosis (TB) following TB treatment completion in HIV-infected individuals remains a major public health burden. We assessed the role of various risk factors in mediating the development of recurrent TB and subsequent resistance to antiretroviral therapy and anti-TB drugs.

Patients and methods

We analyzed secondary demographic, clinical, and laboratory data from medical records of five HIV-infected TB patients enrolled between 2009 and 2014 in a prospective observational study investigating TB recurrence. Paired clinical isolates of Myco-bacterium tuberculosis were typed by IS6110 restriction fragment length polymorphism analysis to determine the mechanism of TB recurrence. Plasma samples were genotyped to determine acquisition of HIV drug resistance mutations on antiretroviral treatment (ART).

Results

All five patients were HIV-coinfected, with a previous history of TB infection and prior exposure to anti-TB treatment, and residual lung damage, and demonstrated poor treatment adherence – significant risk factors linked to the development of recurrent TB disease. Furthermore, three of the five patients had multiple episodes of drug-susceptible TB infection with subsequent drug-resistant TB infection. Genotyping of the initial and recurrent M. tuberculosis isolates demonstrated three cases of recurrent TB because of relapse and two because of reinfection. All five patients had no mutations at ART initiation; however, by the end of the study follow-up, all patients developed dual class resistance.

Conclusion

This series demonstrates the complexity of recurrent TB in HIV coinfection. We highlight the challenges of managing coinfected patients and the increased propensity for the development of drug resistance. We report on the role of various risk factors mediating the development of resistance and subsequent clinical impact. This report underscores the need for structural clinical and adherence interventions for the management of complex treatment and dosing.

Tuberculosis prevention knowledge, attitudes, and practices of primary health care nurses

AIM

Tuberculosis (TB) continues to challenge global health systems, especially in South Africa. Nurses are especially vulnerable to TB exposure, because of their prolonged front-line contact with infected patients-especially in primary health care (PHC) clinics. Their infection control practices, influenced by key factors such as knowledge and attitudes towards TB prevention, become an important consideration. The aim of the study was to (1) describe the TB prevention knowledge, attitudes, and practices of PHC nurses in a South African district and (2) explore moderating factors on TB prevention practices.

METHODS

A cross-sectional survey was undertaken at all 41 PHC facilities in Mangaung Metropolitan district, Free State province, South Africa, using self-administered questionnaires. Captured data were analysed to yield descriptive and multivariate statistics.

RESULTS

Results suggest several instances of inadequate TB prevention knowledge, attitudes, and practices. Good TB practice was predicted by TB attitudes and knowledge, and the relationship between TB prevention knowledge and practices was not moderated by training, attitudes, or nurse category.

CONCLUSION

Results echo previous indications that nurses often do not exhibit the desired knowledge, attitudes, and practices required to adequately protect themselves and others against TB and suggest further exploration towards understanding the influences on TB prevention practice among nurses.

What can National TB Control Programmes in low- and middle-income countries do to end tuberculosis by 2030?

The international community has committed to ending the tuberculosis (TB) epidemic by 2030. This will require multi-sectoral action with a focus on accelerating socio-economic development, developing and implementing new tools, and expanding health insurance coverage. Within this broad framework, National TB Programmes (NTPs) are accountable for delivering diagnostic, treatment, and preventive services. There are large gaps in the delivery of these services, and the aim of this article is to review the crucial activities and interventions that NTPs must implement in order to meet global targets and milestones that will end the TB epidemic. The key deliverables are the following: turn End TB targets and milestones into national measurable indicators to make it easier to track progress; optimize the prompt and accurate diagnosis of all types of TB; provide rapid, complete, and effective treatment to all those diagnosed with TB; implement and monitor effective infection control practices; diagnose and treat drug-resistant TB, associated HIV infection, and diabetes mellitus; design and implement active case finding strategies for high-risk groups and link them to the treatment of latent TB infection; engage with the private-for-profit sector; and empower the Central Unit of the NTP particularly in relation to data-driven supportive supervision, operational research, and sustained financing. The glaring gaps in the delivery of TB services must be remedied, and some of these gaps will require new paradigms and ways of working which include patient-centered and higher-quality services. There must also be fast-track ways of incorporating new diagnostic, treatment, and prevention tools into program activities so as to rapidly reduce TB incidence and mortality and meet the goal of ending TB by 2030.

Genotyping and spatial analysis of pulmonary tuberculosis and diabetes cases in the state of Veracruz, Mexico

Background

Genotyping and georeferencing in tuberculosis (TB) have been used to characterize the distribution of the disease and occurrence of transmission within specific groups and communities.

Objective

The objective of this study was to test the hypothesis that diabetes mellitus (DM) and pulmonary TB may occur in spatial and molecular aggregations.

Material and methods

Retrospective cohort study of patients with pulmonary TB. The study area included 12 municipalities in the Sanitary Jurisdiction of Orizaba, Veracruz, México. Patients with acid-fast bacilli in sputum smears and/or Mycobacterium tuberculosis in sputum cultures were recruited from 1995 to 2010. Clinical (standardized questionnaire, physical examination, chest X-ray, blood glucose test and HIV test), microbiological, epidemiological, and molecular evaluations were carried out. Patients were considered “genotype-clustered” if two or more isolates from different patients were identified within 12 months of each other and had six or more IS6110 bands in an identical pattern, or < 6 bands with identical IS6110 RFLP patterns and spoligotype with the same spacer oligonucleotides. Residential and health care centers addresses were georeferenced. We used a Jeep hand GPS. The coordinates were transferred from the GPS files to ArcGIS using ArcMap 9.3. We evaluated global spatial aggregation of patients in IS6110-RFLP/ spoligotype clusters using global Moran´s I. Since global distribution was not random, we evaluated “hotspots” using Getis-Ord Gi* statistic. Using bivariate and multivariate analysis we analyzed sociodemographic, behavioral, clinic and bacteriological conditions associated with “hotspots”. We used STATA® v13.1 for all statistical analysis.

Results

From 1995 to 2010, 1,370 patients >20 years were diagnosed with pulmonary TB; 33% had DM. The proportion of isolates that were genotyped was 80.7% (n = 1105), of which 31% (n = 342) were grouped in 91 genotype clusters with 2 to 23 patients each; 65.9% of total clusters were small (2 members) involving 35.08% of patients. Twenty three (22.7) percent of cases were classified as recent transmission. Moran`s I indicated that distribution of patients in IS6110-RFLP/spoligotype clusters was not random (Moran`s I = 0.035468, Z value = 7.0, p = 0.00). Local spatial analysis showed statistically significant spatial aggregation of patients in IS6110-RFLP/spoligotype clusters identifying “hotspots” and “coldspots”. GI* statistic showed that the hotspot for spatial clustering was located in Camerino Z. Mendoza municipality; 14.6% (50/342) of patients in genotype clusters were located in a hotspot; of these, 60% (30/50) lived with DM. Using logistic regression the statistically significant variables associated with hotspots were: DM [adjusted Odds Ratio (aOR) 7.04, 95% Confidence interval (CI) 3.03–16.38] and attending the health center in Camerino Z. Mendoza (aOR18.04, 95% CI 7.35–44.28).

Conclusions

The combination of molecular and epidemiological information with geospatial data allowed us to identify the concurrence of molecular clustering and spatial aggregation of patients with DM and TB. This information may be highly useful for TB control programs.

Diagnosis delay of tuberculosis in the Huambo province, Angola

INTRODUCTION

Early diagnosis is necessary for the success of the tuberculosis (TB) program.

GOAL

To identify factors associated with diagnosis delay of TB in Huambo, Angola.

MATERIAL AND METHODS

Cross-sectional study carried out in patients diagnosed with TB at the Huambo Anti-Tuberculosis Dispensary (ATD) in the period between October 2015 and January 2016.

RESULTS

The 247 patients included in the analysis had a median age of 27 years and a median diagnosis delay of 64 days. In the univariate analysis, age, consumption of alcoholic beverages, living in a residence further than 10km from a healthcare unit, and looking for any other health unit than the emergency unit were associated with longer diagnosis delay. In the multivariate analysis model, to be between 30 and 44 years of age (p=0.018), to live in a residence more than 10km from a healthcare unit (p=0.006) and to turn to traditional medicine as the first healthcare option (p<0.001) were factors that led to greater time delay before diagnosis.

CONCLUSIONS

In the Huambo province, age, distance to healthcare facility and the first healthcare service consulted were associated with diagnosis delay of TB.

Protecting Our Front-liners: Occupational Tuberculosis Prevention Through Infection Control Strategies

Healthcare workers (HCWs) in low- and middle-income countries with high tuberculosis prevalence are at increased risk of tuberculosis infection; however, tuberculosis infection control (TBIC) measures are often poorly implemented. The World Health Organization recommends 4 levels of TBIC: managerial (establishment and oversight of TBIC policies), administrative controls (reducing HCWs' exposure to tuberculosis), environmental controls (reducing the concentration of infectious respiratory aerosols in the air), and personal respiratory protection. This article will discuss each of these levels of TBIC, and review the available data on the implementation of each in sub-Saharan African countries. In addition, we review the attitudes and motivation of HCWs regarding TBIC measures, and the impact of stigma on infection control practices and implementation. After summarizing the challenges facing effective TBIC implementation, we will discuss possible solutions and recommendations. Last, we present a case study of how a clinic effectively addressed some of the challenges of TBIC implementation.

Molecular clustering of patients with diabetes and pulmonary tuberculosis: A systematic review and meta-analysis

Introduction

Many studies have explored the relationship between diabetes mellitus (DM) and tuberculosis (TB) demonstrating increased risk of TB among patients with DM and poor prognosis of patients suffering from the association of DM/TB. Owing to a paucity of studies addressing this question, it remains unclear whether patients with DM and TB are more likely than TB patients without DM to be grouped into molecular clusters defined according to the genotype of the infecting Mycobacterium tuberculosis bacillus. That is, whether there is convincing molecular epidemiological evidence for TB transmission among DM patients. Objective: We performed a systematic review and meta-analysis to quantitatively evaluate the propensity for patients with DM and pulmonary TB (PTB) to cluster according to the genotype of the infecting M. tuberculosis bacillus.

Materials and methods

We conducted a systematic search in MEDLINE and LILACS from 1990 to June, 2016 with the following combinations of key words “tuberculosis AND transmission” OR “tuberculosis diabetes mellitus” OR “Mycobacterium tuberculosis molecular epidemiology” OR “RFLP-IS6110” OR “Spoligotyping” OR “MIRU-VNTR”. Studies were included if they met the following criteria: (i) studies based on populations from defined geographical areas; (ii) use of genotyping by IS6110- restriction fragment length polymorphism (RFLP) analysis and spoligotyping or mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR) or other amplification methods to identify molecular clustering; (iii) genotyping and analysis of 50 or more cases of PTB; (iv) study duration of 11 months or more; (v) identification of quantitative risk factors for molecular clustering including DM; (vi) > 60% coverage of the study population; and (vii) patients with PTB confirmed bacteriologically. The exclusion criteria were: (i) Extrapulmonary TB; (ii) TB caused by nontuberculous mycobacteria; (iii) patients with PTB and HIV; (iv) pediatric PTB patients; (v) TB in closed environments (e.g. prisons, elderly homes, etc.); (vi) diabetes insipidus and (vii) outbreak reports. Hartung-Knapp-Sidik-Jonkman method was used to estimate the odds ratio (OR) of the association between DM with molecular clustering of cases with TB. In order to evaluate the degree of heterogeneity a statistical Q test was done. The publication bias was examined with Begg and Egger tests. Review Manager 5.3.5 CMA v.3 and Biostat and Software package R were used.

Results

Selection criteria were met by six articles which included 4076 patients with PTB of which 13% had DM. Twenty seven percent of the cases were clustered. The majority of cases (48%) were reported in a study in China with 31% clustering. The highest incidence of TB occurred in two studies from China. The global OR for molecular clustering was 0.84 (IC 95% 0.40–1.72). The heterogeneity between studies was moderate (I² = 55%, p = 0.05), although there was no publication bias (Beggs test p = 0.353 and Eggers p = 0.429).

Conclusion

There were very few studies meeting our selection criteria. The wide confidence interval indicates that there is not enough evidence to draw conclusions about the association. Clustering of patients with DM in TB transmission chains should be investigated in areas where both diseases are prevalent and focus on specific contexts.

De-isolation of patients with pulmonary tuberculosis after start of treatment - clear, unequivocal guidelines are missing

The study review guidelines on isolation of patients with tuberculosis, TB, from the World Health Organization, WHO, Centers for Disease Control and Prevention, CDC, and the European Center for Disease Control, ECDC. The review found that unequivocal guidelines for removing patients out of negative-pressure isolation and de-isolation patients from either single rooms or isolation at home is needed. Studies show that the time of effective treatment is the key parameter to follow to determine if patients are contagious to others or not. This means that standard treatment of multi-drug resistant, MDR, TB will not result in the patient being non-infectious. Thus it is important right from the time of diagnosis to know if the patient is infected with MDR TB or not. Thus the early use of molecular techniques to reveal drug susceptibility is important. Clear guidelines stating if patient with microscopy negative sputum no matter infected with fully susceptible or MDR TB, no matter HIV positive or not is needed.

WHO strategies for the programmatic management of drug-resistant tuberculosis

INTRODUCTION

Adequate management of drug-resistant tuberculosis (TB), including multidrug- (MDR) and extensively drug-resistant (XDR-) TB are within the priorities of the newly launched World Health Organization's End TB and Elimination Strategies.

AREAS COVERED

This manuscript presents the evidence on the MDR- /XDR-TB epidemiology and discusses how the five recommended priority actions can be applied at the programmatic level to tackle the epidemic: 1) prevent development of MDR-TB thorough high quality treatment of drug- susceptible TB; 2) expand rapid testing and detection of drug-resistant TB; 3) provide immediate access to effective treatment and proper care; 4) prevent transmission through infection control; 5) increase political commitment and financing. A non-systematic review using Pubmed was carried out in addition to additional relevant information taken from the abstracts of international scientific conferences. Expert commentary: Current and future control of MDR-TB significantly relies on the correct use of new diagnostics and new drugs from one side, and on the consistent application of the five core interventions at the programmatic level. In addition, it is mandatory to tackle the social determinants and socio-economic barriers favouring the MDR-TB, otherwise it will not be possible to reach the planned goals as well as TB Elimination.

Tuberculosis infection control practices and associated factors among health care workers in health centers of West Gojjam zone, Northwest Ethiopia: a cross-sectional study

Background

Tuberculosis (TB) remains a major global health problem. The emerging epidemic of multi- and extensively drug-resistant (M/XDR) TB further imperils health workers, patients and public health. Health facilities with inadequate infection control are risky environments for the emergence and transmission of TB. There was no study that presented data on infection control practices of health care workers. This study aimed to assess tuberculosis infection control practices and associated factors among health care workers in West Gojjam Zone, Northwest Ethiopia.

Methods

Institution based quantitative cross-sectional study triangulated with qualitative observation and key informant interview was conducted. Six hundred sixty two health care workers were selected by multistage random sampling method. Self-administered structured questionnaire was used to collect quantitative data. Observation checklists and key informant interview guides were used to collect qualitative data. Quantitative data were entered in to Epi Info version 3.5.3 and analyzed using SPSS version 20. Odds ratio with 95 % confidence interval was used to identify factors associated with TB infection control practice of health care workers. Qualitative data were translated, transcribed, analyzed and triangulated with the quantitative findings.

Results

The proportion of proper TB infection control (TBIC) practices was 38 %. Qualitative data showed that administrative, environmental and personal respiratory protection control measures were not practiced well. Knowledge on the presence of TBIC plan [AOR = 4.25, 95 % CI: 2.46 - 7.35], knowledge on the presence of national guideline [AOR = 8.95, 95 % CI: 4.35 - 18.40] and working department of the health care workers were independent predictors of TBIC practices.

Conclusions

The proportion of proper TBIC practices of health care workers was low. TBIC practices were determined by knowing the presence of TBIC plan and national guideline and working department. Hence, supportive supervision and trainings should be given to health care workers who are working other than TB clinics to improve the knowledge of TBIC plan and guidelines. Health centers shall prepare TBIC plans and orient all health care workers.

Protocol for a population-based molecular epidemiology study of tuberculosis transmission in a high HIV-burden setting: the Botswana Kopanyo study

INTRODUCTION

Mycobacterium tuberculosis (Mtb) is transmitted from person to person via airborne droplet nuclei. At the community level, Mtb transmission depends on the exposure venue, infectiousness of the tuberculosis (TB) index case and the susceptibility of the index case's social network. People living with HIV infection are at high risk of TB, yet the factors associated with TB transmission within communities with high rates of TB and HIV are largely undocumented. The primary aim of the Kopanyo study is to better understand the demographic, clinical, social and geospatial factors associated with TB and multidrug-resistant TB transmission in 2 communities in Botswana, a country where 60% of all patients with TB are also infected with HIV. This manuscript describes the methods used in the Kopanyo study.

METHODS AND ANALYSIS

The study will be conducted in greater Gaborone, which has high rates of HIV and a mobile population; and in Ghanzi, a rural community with lower prevalence of HIV infection and home to the native San population. Kopanyo aims to enrol all persons diagnosed with TB during a 4-year study period. From each participant, sputum will be cultured, and for all Mtb isolates, molecular genotyping (24-locus mycobacterial interspersed repetitive units-variable number of tandem repeats) will be performed. Patients with matching genotype results will be considered members of a genotype cluster, a proxy for recent transmission. Demographic, behavioural, clinical and social information will be collected by interview. Participant residence, work place, healthcare facilities visited and social gathering venues will be geocoded. We will assess relationships between these factors and cluster involvement to better plan interventions for reducing TB transmission.

ETHICS

Ethical approval from the Independent Review Boards at the University of Pennsylvania, US Centers for Disease Control and Prevention, Botswana Ministry of Health and University of Botswana has been obtained.

Protecting health workers from infectious disease transmission: an exploration of a Canadian-South African partnership of partnerships

BACKGROUND

Health workers are at high risk of acquiring infectious diseases at work, especially in low and middle-income countries (LMIC) with critical health human resource deficiencies and limited implementation of occupational health and infection control measures. Amidst increasing interest in international partnerships to address such issues, how best to develop such collaborations is being actively debated. In 2006, a partnership developed between occupational health and infection control experts in Canada and institutions in South Africa (including an institute with a national mandate to conduct research and provide guidance to protect health workers from infectious diseases and promote improved working conditions). This article describes the collaboration, analyzes the determinants of success and shares lessons learned.

METHODS

Synthesizing participant-observer experience from over 9 years of collaboration and 10 studies already published from this work, we applied a realist review analysis to describe the various achievements at global, national, provincial and hospital levels. Expectations of the various parties on developing new insights, providing training, and addressing service needs were examined through a micro-meso-macro lens, focusing on how each main partner organization contributed to and benefitted from working together.

RESULTS

A state-of-the-art occupational health and safety surveillance program was established in South Africa following successful technology transfer from a similar undertaking in Canada and training was conducted that synergistically benefitted Northern as well as Southern trainees. Integrated policies combining infection control and occupational health to prevent and control infectious disease transmission among health workers were also launched. Having a national (South-South) network reinforced by the international (North-south) partnership was pivotal in mitigating the challenges that emerged.

CONCLUSIONS

High-income country partnerships with experience in health system strengthening - particularly in much needed areas such as occupational health and infection control - can effectively work through strong collaborators in the Global South to build capacity. Partnerships are particularly well positioned to sustainably reinforce efforts at national and sub-national LMIC levels when they adopt a "communities of practice" model, characterized by multi-directional learning. The principles of effective collaboration learned in this "partnership of partnerships" to improve working conditions for health workers can be applied to other areas where health system strengthening is needed.

Comparison of indoor contact time data in Zambia and Western Cape, South Africa suggests targeting of interventions to reduce Mycobacterium tuberculosis transmission should be informed by local data

Background

In high incidence settings, the majority of Mycobacterium tuberculosis (M.tb) transmission occurs outside the household. Little is known about where people’s indoor contacts occur outside the household, and how this differs between different settings. We estimate the number of contact hours that occur between adults and adult/youths and children in different building types in urban areas in Western Cape, South Africa, and Zambia.

Methods

Data were collected from 3206 adults using a cross-sectional survey, on buildings visited in a 24-h period, including building function, visit duration, and number of adults/youths and children (5–12 years) present. The mean numbers of contact hours per day by building function were calculated.

Results

Adults in Western Cape were more likely to visit workplaces, and less likely to visit shops and churches than adults in Zambia. Adults in Western Cape spent longer per visit in other homes and workplaces than adults in Zambia. More adults/youths were present at visits to shops and churches in Western Cape than in Zambia, and fewer at homes and hairdressers. More children were present at visits to shops in Western Cape than in Zambia, and fewer at schools and hairdressers. Overall numbers of adult/youth indoor contact hours were the same at both sites (35.4 and 37.6 h in Western Cape and Zambia respectively, p = 0.4). Child contact hours were higher in Zambia (16.0 vs 13.7 h, p = 0.03). Adult/youth and child contact hours were highest in workplaces in Western Cape and churches in Zambia. Compared to Zambia, adult contact hours in Western Cape were higher in workplaces (15.2 vs 8.0 h, p = 0.004), and lower in churches (3.7 vs 8.6 h, p = 0.002). Child contact hours were higher in other peoples’ homes (2.8 vs 1.6 h, p = 0.03) and workplaces (4.9 vs 2.1 h, p = 0.003), and lower in churches (2.5 vs 6.2, p = 0.004) and schools (0.4 vs 1.5, p = 0.01).

Conclusions

Patterns of indoor contact between adults and adults/youths and children differ between different sites in high M.tb incidence areas. Targeting public buildings with interventions to reduce M.tb transmission (e.g. increasing ventilation or UV irradiation) should be informed by local data.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1406-5) contains supplementary material, which is available to authorized users.

One-stop TB-HIV services evaluation in Rwanda: comparison of the 2001-2005 and 2006-2010 cohorts

BACKGROUND

Tuberculosis (TB) and human immunodeficiency virus (HIV) co-infection remains high in Rwanda. Since one-stop TB-HIV services were implemented to manage TB-HIV co-infection, their functioning and impact on TB treatment outcomes have not been assessed.

OBJECTIVE

To evaluate one-stop TB-HIV services in Rwanda by comparing the TB treatment outcomes before and after their implementation in Kicukiro and Rulindo districts.

METHODS

This descriptive retrospective study used a quantitative questionnaire to determine the functioning of Rwanda's one-stop TB-HIV services. In-depth interviews and focus group discussions with health care providers, heads of facilities and co-infected patients were held to seek their opinion about the functioning of the services.

RESULTS

The one-stop TB-HIV services at all 12 health facilities visited were functioning according to the approved criteria. However, TB treatment outcomes after the intervention were not statistically different from those before the intervention. Qualitative data showed a positive impact on the quality of service, particularly a reduction in waiting times and appointments that were better respected as a result of the efficient functioning of the services.

CONCLUSION

One-stop TB-HIV services have improved the quality of service in Kicukiro and Rulindo districts. However, the services need to be strengthened programmatically to improve TB treatment outcomes.

Integrating tuberculosis and HIV services in rural Kenya: uptake and outcomes

SETTING

Seventeen rural public health facilities in Western Kenya that introduced three models of integrated care for tuberculosis (TB) and human immunodeficiency virus (HIV) patients.

OBJECTIVE

To assess the uptake and timing of cotrimoxazole preventive therapy (CPT) and antiretroviral treatment (ART) as well as anti-tuberculosis treatment outcomes among HIV-infected TB patients before (March-October 2010) and after (March-October 2012) the introduction of integrated TB-HIV care.

DESIGN

A before-and-after cohort study using programme data.

RESULTS

Of 501 HIV-infected TB patients, 357 (71%) were initiated on CPT and 178 (39%) on ART in the period before the introduction of integrated TB-HIV care. Following the integration of services, respectively 316 (98%) and 196 (61%) of 323 HIV-infected individuals were initiated on CPT and on ART (P < 0.001). The median time to CPT and ART initiation dropped from 7 to 2 days and from 42 to 34 days during the pre- and post-integration phases, respectively. Overall TB success rates did not vary with integration or with type of model instituted.

CONCLUSION

Integration of TB and HIV services enhanced uptake and reduced delay in instituting CPT and ART in rural health facilities. There is a need to increase impetus in these efforts.

Development of tuberculosis infection control guidelines in a pediatric HIV clinic in sub-Saharan Africa

SETTING

A well-established pediatric human immunodeficiency virus (HIV) clinic in Lesotho with initial infection control (IC) measures prioritizing blood-borne disease. In line with international recommendations, services have been expanded to include the management of patients with tuberculosis (TB). The creation of comprehensive IC guidelines with an emphasis on TB has become a priority.

OBJECTIVE

To provide a model for developing and implementing IC guidelines in ambulatory care facilities in limited-resource settings with high HIV and TB prevalence. Activities: An IC plan that includes guidance covering both general IC measures and TB-specific guidelines was created by integrating local and international recommendations and emphasizing the importance of administrative measures, environmental controls, and disease-specific precautions. An interdisciplinary committee was established to oversee its implementation, monitoring, and evaluation.

DISCUSSION

Development and implementation of IC guidelines in resource-limited settings are feasible and should be a priority in high HIV and TB prevalence areas. Education should be the cornerstone of such endeavors. Many interventions can be implemented with minimal expertise and material resources. Administrative support and institutional investment are essential to the sustainability of an effective IC program.

TB screening among people living with HIV/AIDS in resource-limited settings

Tuberculosis (TB) continues to be the leading cause of morbidity and mortality among people living with HIV (PLHIV), making improved prevention and treatment of HIV-associated TB critical to ensuring long-term survival of PLHIV. TB screening among PLHIV is central to implementation of the World Health Organization's 3 I's interventions for reducing the impact of the TB and HIV syndemics. Effective TB screening will result in the identification of PLHIV with presumptive TB disease (ie, those with a positive symptom screen who require appropriate evaluation, including the use of diagnostic tools such as the Xpert MTB/RIF assay) and those eligible for isoniazid preventive therapy (ie, those who have a negative clinical symptom screen or who have a positive screen but are found not to have TB disease). Identification of PLHIV with presumptive TB also facilitates implementation of basic administrative measures for TB infection control, including fast tracking of coughing patients and separation from noncoughing PLHIV to reduce TB transmission. By contributing to the early diagnosis of TB disease among PLHIV, TB screening is also critical to facilitate early initiation of antiretroviral treatment among PLHIV diagnosed with TB disease who might not otherwise be eligible for antiretroviral treatment based on CD4 count or clinical staging. TB screening thus serves as a gateway for multiple TB/HIV interventions and is an integral part of routine clinical services for PLHIV at each clinic visit.

Latent Tuberculosis Infection and Associated Factors among Health Care Workers in Kigali, Rwanda

INTRODUCTION

Data are limited regarding tuberculosis (TB) and latent TB infection prevalence in Rwandan health facilities.

METHODS

We conducted a cross-sectional survey among healthcare workers (HCWs) in Kigali during 2010. We purposively selected the public referral hospital, both district hospitals, and randomly selected 7 of 17 health centers. School workers (SWs) from the nearest willing public schools served as a local reference group. We tested for latent TB infection (LTBI) using tuberculin skin testing (TST) and asked about past TB disease. We assessed risk of LTBI and past history of TB disease associated with hospital employment. Among HCWs, we assessed risk associated with facility type (district hospital, referral hospital, health center), work setting (inpatient, outpatient), and occupation.

RESULTS

Age, gender, and HIV status was similar between the enrolled 1,131 HCWs and 381 SWs. LTBI was more prevalent among HCWs (62%) than SWs (39%). Adjusted odds of a positive TST result were 2.71 (95% CI 2.01-3.67) times greater among HCWs than SWs. Among HCWs, there was no detectable difference between prevalence of LTBI according to facility type, work setting, or occupation.

CONCLUSION

HCWs are at greater risk of LTBI, regardless of facility type, work setting, or occupation. The current status of TB infection control practices should be evaluated in the entire workforce in all Rwandan healthcare facilities.

The role of the law in reducing tuberculosis transmission in Botswana, South Africa and Zambia

OBJECTIVE

To determine whether laws and regulations in Botswana, South Africa and Zambia - three countries with a high tuberculosis and HIV infection burden - address elements of the World Health Organization (WHO) policy on tuberculosis infection control.

METHODS

An online desk review of laws and regulations that address six selected elements of the WHO policy on tuberculosis infection control in the three countries was conducted in November 2015 using publicly available domestic legal databases. The six elements covered: (i) national policy and legal framework; (ii) health facility design, construction and use; (iii) tuberculosis disease surveillance among health workers; (iv) patients' and health workers' rights; (v) monitoring of infection control measures; and (vi) relevant research.

FINDINGS

The six elements were found to be adequately addressed in the three countries' laws and regulations. In all three, tuberculosis case-reporting is required, as is tuberculosis surveillance among health workers. Each country's legal and regulatory framework also addresses the need to respect individuals' rights and privacy while safeguarding public health. These laws and regulations create a strong foundation for tuberculosis infection control. Although the legal and regulatory frameworks thoroughly address tuberculosis infection control, their dissemination, implementation and enforcement were not assessed, nor was their impact on public health.

CONCLUSION

Laws and regulations in Botswana, South Africa and Zambia address all six selected elements of the WHO policy on tuberculosis infection control. However, the lack of data on their implementation is a limitation. Future research should assess the implementation and public health impact of laws and regulations.

Determinants of tuberculosis infection control-related behaviors among healthcare workers in the country of Georgia

OBJECTIVE

To better understand tuberculosis (TB) infection control (IC) in healthcare facilities (HCFs) in Georgia.

DESIGN

A cross-sectional evaluation of healthcare worker (HCW) knowledge, beliefs and behaviors toward TB IC measures including latent TB infection (LTBI) screening and treatment of HCWs.

SETTING

Georgia, a high-burden multidrug-resistant TB (MDR-TB) country.

PARTICIPANTS

HCWs from the National TB Program and affiliated HCFs.

METHODS

An anonymous self-administered 55-question survey developed based on the Health Belief Model (HBM) conceptual framework.

RESULTS

In total, 240 HCWs (48% physicians; 39% nurses) completed the survey. The overall average TB knowledge score was 61%. Only 60% of HCWs reported frequent use of respirators when in contact with TB patients. Only 52% of HCWs were willing to undergo annual LTBI screening; 48% were willing to undergo LTBI treatment. In multivariate analysis, HCWs who worried about acquiring MDR-TB infection (adjusted odds ratio [aOR], 1.7; 95% confidence interval [CI], 1.28-2.25), who thought screening contacts of TB cases is important (aOR, 3.4; 95% CI, 1.35-8.65), and who were physicians (aOR, 1.7; 95% CI, 1.08-2.60) were more likely to accept annual LTBI screening. With regard to LTBI treatment, HCWs who worked in an outpatient TB facility (aOR, 0.3; 95% CI, 0.11-0.58) or perceived a high personal risk of TB reinfection (aOR, 0.5; 95% CI, 0.37-0.64) were less likely to accept LTBI treatment.

CONCLUSION

The concern about TB reinfection is a major barrier to HCW acceptance of LTBI treatment. TB IC measures must be strengthened in parallel with or prior to the introduction of LTBI screening and treatment of HCWs.

Global epidemiology of tuberculosis

Despite the availability of effective chemotherapy, tuberculosis (TB) killed 1.3 million people in 2012. Alongside HIV, it remains a top cause of death from an infectious disease. Global targets for reductions in the epidemiological burden of TB have been set for 2015 and 2050 within the context of the Millennium Development Goals (MDGs) and by the Stop TB Partnership. Achieving these targets is the focus of national and international efforts in TB control, and showing whether or not they are achieved is of major importance to guide future and sustainable investments. This article provides a short overview of sources of data to estimate TB disease burden; presents estimates of TB incidence, prevalence, and mortality in 2012 and an assessment of progress toward the 2015 targets for reductions in these indicators based on trends since 1990 and projections up to 2015; analyzes trends in TB notifications and in the implementation of the Stop TB Strategy; and considers prospects for elimination of TB after 2015.

Longer hospital stay is associated with higher rates of tuberculosis-related morbidity and mortality within 12 months after discharge in a referral hospital in Sub-Saharan Africa

Background

Nosocomial transmission of pulmonary tuberculosis (PTB) is a problem in resource-limited settings. However, the degree of TB exposure and the intermediate- and long-term morbidity and mortality of hospital-associated TB is unclear. In this study we determined: 1) the nature, patterns and intensity of TB exposure occurring in the context of current TB cohorting practices in medical centre with a high prevalence of TB and HIV; 2) the one-year TB incidence after discharge; and 3) one-year TB-related mortality after hospital discharge.

Methods

Factors leading to nosocomial TB exposure were collected daily over a 3-month period. Patients were followed for 1-year after discharge. TB incidence and mortality were calculated and logistic regression was used to determine the factors associated with TB incidence and mortality during follow up.

Results

1,094 patients were admitted to the medical wards between May 01 and July 31, 2010. HIV was confirmed in 690/1,094 (63.1%) of them. A total of 215/1,094 (19.7%) patients were diagnosed with PTB and 178/1,094 (16.3%) patients died during the course of their hospitalization; 12/178 (6.7%) patients died from TB-related complications. Eventually, 916 (83.7%) patients were discharged and followed for one year after it. Of these, 51 (5.6%) were diagnosed with PTB during the year of follow up (annual TB rate of 3,712 cases per 100,000 person per year). Overall, 57/916 (6.2%) patients died during the follow up period, of whom 26/57 (45.6%) died from confirmed TB. One-year TB incidence rate and TB-associated mortality were associated with the number of days that the patient remained hospitalized, the number of days spent in the cohorting bay (regardless of whether the patient was eventually diagnosed with TB or not), and the number and proximity to TB index cases. There was no difference in the performance of each of these 3 measurements of nosocomial TB exposure for the prediction of one-year TB incidence.

Conclusion

Substantial TB exposure, particularly among HIV-infected patients, occurs in nosocomial settings despite implementation of cohorting measures. Nosocomial TB exposure is strongly associated with one-year TB incidence and TB-related mortality. Further studies are needed to identify strategies to reduce such exposure among susceptible patients.

Management of patients with multidrug-resistant/extensively drug-resistant tuberculosis in Europe: a TBNET consensus statement

The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) substantially challenges TB control, especially in the European Region of the World Health Organization, where the highest prevalence of MDR/XDR cases is reported. The current management of patients with MDR/XDR-TB is extremely complex for medical, social and public health systems. The treatment with currently available anti-TB therapies to achieve relapse-free cure is long and undermined by a high frequency of adverse drug events, suboptimal treatment adherence, high costs and low treatment success rates. Availability of optimal management for patients with MDR/XDR-TB is limited even in the European Region. In the absence of a preventive vaccine, more effective diagnostic tools and novel therapeutic interventions the control of MDR/XDR-TB will be extremely difficult. Despite recent scientific advances in MDR/XDR-TB care, decisions for the management of patients with MDR/XDR-TB and their contacts often rely on expert opinions, rather than on clinical evidence.

This document summarises the current knowledge on the prevention, diagnosis and treatment of adults and children with MDR/XDR-TB and their contacts, and provides expert consensus recommendations on questions where scientific evidence is still lacking.

TBNET consensus statement on the management of patients with MDR/XDR-TB has been released in theEur Respir Jhttp://ow.ly/uizRD

Intensified tuberculosis case-finding in HIV-positive adults managed at Ethiopian health centers: diagnostic yield of Xpert MTB/RIF compared with smear microscopy and liquid culture

Background

Detection of active tuberculosis (TB) before antiretroviral therapy (ART) initiation is important, but optimal diagnostic methods for use in resource-limited settings are lacking. We assessed the prevalence of TB, evaluated the diagnostic yield of Xpert MTB/RIF in comparison with smear microscopy and culture, and the impact of Xpert results on clinical management in HIV-positive adults eligible for ART at health centers in a region of Ethiopia.

Methods

Participants were prospectively recruited and followed up at 5 health centers. Trained nurses collected data on socio-demographic characteristics, medical history and symptoms, and performed physical examination. Two paired morning sputum samples were obtained, and lymph node aspirates in case of lymphadenopathy. Diagnostic yield of Xpert MTB/RIF in sputum was compared with smear microscopy and liquid culture.

Results

TB was diagnosed in 145/812 participants (17.9%), with bacteriological confirmation in 137 (16.9%). Among bacteriologically confirmed cases, 31 were smear-positive (22.6%), 96 were Xpert-positive (70.1%), and 123 were culture-positive (89.8%). Xpert MTB/RIF increased the TB detection rate by 64 cases (47.4%) compared with smear microscopy. The overall sensitivity of Xpert MTB/RIF was 66.4%, and was not significantly lower when testing one compared with two samples. While Xpert MTB/RIF was 46.7% sensitive among patients with CD4 cell counts >200 cells/mm³, this increased to 82.9% in those with CD4 cell counts ≤100 cells/mm³. Compared with Xpert-positive TB patients, Xpert-negative cases had less advanced HIV and TB disease characteristics.

Conclusions

Previously undiagnosed TB is common among HIV-positive individuals managed in Ethiopian health centers. Xpert MTB/RIF increased TB case detection, especially in patients with advanced immunosuppression. An algorithm based on the use of a single morning sputum sample for individuals with negative sputum smear microscopy could be considered for intensified case finding in patients eligible for ART. However, technical and cost-effectiveness issues relevant for low-income countries warrant further study.

Cost utility of lateral-flow urine lipoarabinomannan for tuberculosis diagnosis in HIV-infected African adults

SETTING

In-patient hospitals in South Africa and Uganda.

OBJECTIVE

To evaluate the cost-effectiveness of a lateral-flow urine lipoarabinomannan (LAM) test when added to existing strategies for tuberculosis (TB) diagnosis in human immunodeficiency virus infected adults (CD4(+) T-cell counts < 100 cells/l) with symptoms of active TB.

DESIGN

Decision-analytic cost-utility model, with the primary outcome being the incremental cost-effectiveness ratio, expressed in 2010 US dollars per disability-adjusted life year (DALY) averted from the perspective of a public sector TB control program.

RESULTS AND CONCLUSION

For every 1000 patients tested, adding lateral-flow urine LAM generated 80 incremental appropriate anti-tuberculosis treatments and averted 224 DALYs. Estimated cost utility was US$353 per DALY averted (95% uncertainty range $192$1161) in South Africa and $86 per DALY averted (95% uncertainty range $49$239) in Uganda, reflecting the lower treatment costs in Uganda. Cost utility was most sensitive to assay specificity, cost of anti-tuberculosis treatment, life expectancy after TB cure and cohort TB prevalence, but did not rise above $1500 per DALY averted in South Africa under any one-way sensitivity analysis. The probability of acceptability was >99.8% at a per-DALY willingness-to-pay threshold equal to the per capita gross domestic product in South Africa ($7275) and Uganda ($509).

Preventing nosocomial MDR TB transmission in sub Saharan Africa: where are we at?

BACKGROUND

In sub Saharan Africa, the cocktail of many advanced HIV-infected susceptible hosts, poor TB treatment success rates, a lack of airborne infection control, limited drug-resistance testing (DST) have resulted in HIV-infected individuals being  disproportionately represented in Multi drug resistant Tuberculosis (MDR-TB) cases. The prevailing application of the WHO re-treatment protocol indiscriminately to all re-treatment cases sets the stage for an increase in mortality and MDR-TB nosocomial transmission.

METHOD

A comprehensive search was performed of the Cochrane Infectious Diseases Group Specialized Register and Medline database including the bibliographies of the retrieved reference.

FINDINGS

The TB diagnosis paradigm which for decades relied on smear sputum and culture is likely to change with the advent of the point-of-care diagnostic, Xpert MTB/RIF assay. Until the new DST infrastructure is available, along with clinical trials for both, current and new approaches to retreatment TB in areas heavily affected by HIV and TB, there are cost effective administrative, environmental, and protective measures that may be immediately instituted.

CONCLUSION

The severe lack of infection control practices in sub Saharan Africa may jeopardise the recent strides in MDR-TB management. Cost effective infection control measures must be immediately implemented, otherwise the development of further drug resistance may offset recent strides in MDR-TB management. Indiscriminate use of the WHO standardized retreatment protocol can lead to nosocomial transmission of MDR-TB by: -Precluding early diagnosis and prompt separation of patients who experienced treatment failure category and thereby more likely to have MDR-TB. -Leaving patients from the treatment failure category in health establishments on ineffective standard retreatment regimen until the DST results are known. -targeting only patients who have had prior TB therapy, new severely debilitated TB patients having primary unrecognized MDR-TB may continue spreading resistant organisms.

Nosocomial transmission of extensively drug-resistant tuberculosis in a rural hospital in South Africa

BACKGROUND

Extensively drug-resistant tuberculosis (XDR-tuberculosis) is a global public health threat, but few data exist elucidating factors driving this epidemic. The initial XDR-tuberculosis report from South Africa suggested transmission is an important factor, but detailed epidemiologic and molecular analyses were not available for further characterization.

METHODS

We performed a retrospective, observational study among XDR-tuberculosis patients to identify hospital-associated epidemiologic links. We used spoligotyping, IS6110-based restriction fragment-length polymorphism analysis, and sequencing of resistance-determining regions to identify clusters. Social network analysis was used to construct transmission networks among genotypically clustered patients.

RESULTS

Among 148 XDR-tuberculosis patients, 98% were infected with human immunodeficiency virus (HIV), and 59% had smear-positive tuberculosis. Nearly all (93%) were hospitalized while infectious with XDR-tuberculosis (median duration, 15 days; interquartile range: 10-25 days). Genotyping identified a predominant cluster comprising 96% of isolates. Epidemiologic links were identified for 82% of patients; social network analysis demonstrated multiple generations of transmission across a highly interconnected network.

CONCLUSIONS

The XDR-tuberculosis epidemic in Tugela Ferry, South Africa, has been highly clonal. However, the epidemic is not the result of a point-source outbreak; rather, a high degree of interconnectedness allowed multiple generations of nosocomial transmission. Similar to the outbreaks of multidrug-resistant tuberculosis in the 1990s, poor infection control, delayed diagnosis, and a high HIV prevalence facilitated transmission. Important lessons from those outbreaks must be applied to stem further expansion of this epidemic.

Association of diabetes and tuberculosis: impact on treatment and post-treatment outcomes

Objective

To determine the clinical consequences of pulmonary tuberculosis (TB) among patients with diabetes mellitus (DM).

Methods

We conducted a prospective study of patients with TB in Southern Mexico. From 1995 to 2010, patients with acid-fast bacilli or Mycobacterium tuberculosis in sputum samples underwent epidemiological, clinical and microbiological evaluation. Annual follow-ups were performed to ascertain treatment outcome, recurrence, relapse and reinfection.

Results

The prevalence of DM among 1262 patients with pulmonary TB was 29.63% (n=374). Patients with DM and pulmonary TB had more severe clinical manifestations (cavities of any size on the chest x-ray, adjusted OR (aOR) 1.80, 95% CI 1.35 to 2.41), delayed sputum conversion (aOR 1.51, 95% CI 1.09 to 2.10), a higher probability of treatment failure (aOR 2.93, 95% CI 1.18 to 7.23), recurrence (adjusted HR (aHR) 1.76, 95% CI 1.11 to 2.79) and relapse (aHR 1.83, 95% CI 1.04 to 3.23). Most of the second episodes among patients with DM were caused by bacteria with the same genotype but, in 5/26 instances (19.23%), reinfection with a different strain occurred.

Conclusions

Given the growing epidemic of DM worldwide, it is necessary to add DM prevention and control strategies to TB control programmes and vice versa and to evaluate their effectiveness. The concurrence of both diseases potentially carries a risk of global spreading, with serious implications for TB control and the achievement of the United Nations Millennium Development Goals.

Reducing deaths from tuberculosis in antiretroviral treatment programmes in sub-Saharan Africa

Mortality rates are high in antiretroviral therapy (ART) programmes in sub-Saharan Africa, especially during the first few months of treatment. Tuberculosis (TB) has been identified as a major underlying cause. Under routine programme conditions, between 5 and 40% of adult patients enrolling in ART services have a baseline diagnosis of TB. There is also a high TB incidence during the first few months of ART (much of which is prevalent disease missed by baseline screening) and long-term rates remain several-folds higher than background. We identify three groups of patients entering ART programmes for which different interventions are required to reduce TB-related deaths. First, diagnostic screening is needed in patients who have undiagnosed active TB so that timely anti-TB treatment can be started. This may be greatly facilitated by new diagnostic assays such as the Xpert MTB/RIF assay. Second, patients with a diagnosis of active TB need optimized case management, which includes early initiation of ART (with timing now defined by randomized controlled trials), trimethoprim-sulphamethoxazole prophylaxis and treatment of comorbidity. Third, all remaining patients who are TB-free at enrolment have high ongoing risk of developing TB and require preventive interventions, including optimized immune recovery (with ART ideally started early in the course of HIV infection), isoniazid preventive therapy and infection control to reduce infection risk. Further specific measures are needed to address multidrug-resistant TB (MDR-TB). Finally, scale-up of all these interventions requires nationally and locally tailored models of care that are patient-centred and provide integrated healthcare delivery for TB, HIV and other comorbidities.

Multidrug- and extensively drug-resistant TB in persons living with HIV

Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) represent an emerging public health problem worldwide. The collision of the HIV epidemic with MDR- and XDR-TB has produced disastrous consequences for individual patients, with very high mortality rates reported in outbreaks among HIV-infected individuals. There is evidence of the importance of primary resistance among HIV-infected persons with XDR-TB, while the relevance of acquired resistance during inappropriate treatment among HIV-infected persons is uncertain, and TB case management of HIV-infected and -uninfected persons is based on similar standard practices to ensure treatment adherence. Current data show a limited geographical overlap of the XDR-TB and HIV epidemics: such data must be interpreted cautiously owing to the lack of adequate testing for both conditions. In fact, there are signs of an evolving epidemiological situation characterized by increased outbreak risk in concentrated areas owing to the extension of the HIV epidemic into areas of high MDR-TB prevalence and of the MDR-TB epidemic into areas of high HIV prevalence. There is a paucity of studies on treatment outcome among HIV-infected XDR-TB patients, and the only available report shows extremely high mortality rate and very short survival. Rapid diagnosis of TB and MDR-TB will be pivotal to reduce mortality among persons co-infected with HIV. However, while rapid diagnosis of MDR-TB is feasible with molecular assays on direct specimens, molecular approaches are still insensitive for XDR-TB diagnosis. There is speculative evidence that effective strategies for early HIV diagnosis and treatment will play a role in limiting the spread, and possibly improving the outcome of XDR-TB. Prevention is currently the mainstay of XDR-TB control in HIV communities. Strategies for infection control based on administrative procedures, environmental control and respiratory protection should be a priority for countries where both XDR-TB and HIV are prevalent. However, only the comprehensive implementation of the full Stop TB Strategy may be expected to curb the devastating impact of XDR-TB on HIV-infected persons.

Training laboratory technicians from the Ethiopian periphery in the MODS technique enables rapid and low-cost diagnosis of Mycobacterium tuberculosis infection

Tuberculosis (TB) is a leading cause of morbidity and mortality and is frequently complicated by emergence of drug-resistant strains. Diagnosis of TB in developing countries is often based on the relatively insensitive acid-fast staining that does not enable susceptibility profiling. Microscopic observation drug susceptibility assay (MODS) is an inexpensive, simple method that enables rapid TB culture coupled with susceptibility testing. A 3-week MODS training of three Ethiopian laboratory technicians was conducted at Hadassah-Hebrew University Medical Center, Israel. Results of the trainee readings were blindly assessed by an experienced instructor. Two hundred fifty-five (255) trainee culture readings were evaluated throughout the course. The sensitivity and specificity were 75-100% and 31.5-100%, respectively. Multivariate analysis revealed that sensitivity and duration of incubation were positively correlated, although specificity was positively correlated with the length of training. MODS can be reliably performed by laboratory technicians inexperienced in culture techniques in developing countries, with high sensitivity and specificity reached after a brief learning period.

Characteristics and early outcomes of patients with Xpert MTB/RIF-negative pulmonary tuberculosis diagnosed during screening before antiretroviral therapy

Comparison of the characteristics of HIV-infected patients with Xpert-positive and Xpert-negative tuberculosis and relationship of Xpert status with subsequent clinical and programmatic outcomes.

Background. A proportion of patients with tuberculosis diagnosed by sputum culture during screening before antiretroviral therapy (ART) have false-negative Xpert MTB/RIF assay results (Xpert-negative tuberculosis). We determined the characteristics and early ART program outcomes of such patients.

Methods. Adult patients who enrolled in a South African township ART service were systematically screened for pulmonary tuberculosis regardless of symptoms by testing paired sputum samples with Xpert MTB/RIF and liquid culture. The ART service provided follow-up for all patients, and early (90-day) programmatic outcomes were determined.

Results. Among 602 patients screened, 523 had ≥1 Xpert and culture result, yielding 89 culture-positive tuberculosis diagnoses. Of these, 37 (42%) of the patients with tuberculosis were Xpert-negative when a single sputum sample was tested, compared with 25 (28%) when 2 samples were tested. Compared with patients with Xpert-positive tuberculosis, those with Xpert-negative tuberculosis (using either definition) had substantially higher CD4 cell counts, lower plasma viral loads, higher hemoglobin concentrations, and higher body mass index. Their tuberculosis was also less advanced, with a lower frequency of prolonged cough (≥2 weeks), less extensive radiographic abnormalities, and a lower frequency of detectable lipoarabinomannan antigenuria and mycobacteriuria. Xpert-negative cases were all sputum smear negative with prolonged time to culture positivity (median, 21 days). Despite greater delays in starting tuberculosis treatment, Xpert-negative patients were less likely to die during follow-up.

Conclusions. Compared to patients with Xpert-positive tuberculosis diagnosed during pre-ART screening, Xpert-negative cases had less advanced immunosuppression and less advanced tuberculosis and did not have adverse outcomes despite substantial delays in starting tuberculosis treatment.

Tuberculosis infection control in a high drug-resistance setting in rural South Africa: information, motivation, and behavioral skills

BACKGROUND

Tuberculosis (TB) is transmitted in resource-limited facilities where TB infection control (IC) is poorly implemented. Theory-based behavioral models can potentially improve IC practices.

METHODS

The present study used an anonymous questionnaire to assess healthcare worker (HCW) TB IC information, motivation, and behavioral skills (IMB) and implementation in two resource-limited rural South African hospitals with prevalent drug-resistant TB.

RESULTS

Between June and August 2010, 198 surveys were completed. Although the respondents demonstrated information proficiency and positive motivation, 22.8% did not consider TB IC to be worthwhile. Most tasks were rated as easy by survey participants, but responding HCWs highlighted challenges in discrete behavioral skills. The majority of responding HCWs reported that they always wore respirators (54.3%), instructed patients on cough hygiene (63.0%), and ensured natural ventilation (67.4%) in high-risk areas. Most respondents (74.0%) knew their HIV status. Social support items correlated with the implementation of the first three aforementioned practices but not with the respondents' knowledge of their HIV status. In most cases, motivation and behavioral skills, but not information, were associated with implementation.

CONCLUSION

HCWs in rural South African hospitals with high drug-resistance demonstrated moderate IMB and implementation of TB IC. Improvement efforts should emphasize the development of HCW motivation and behavioral skills as well as social support from colleagues and supervisors. Such interventions should be informed by baseline IMB assessments. In the present study, a trimmed/modified IMB model helped characterize TB IC implementation.

Tuberculosis in antiretroviral treatment services in resource-limited settings: addressing the challenges of screening and diagnosis

The high burden of tuberculosis (TB) among patients accessing antiretroviral treatment (ART) services in resource-limited settings is a major cause of morbidity and mortality and is associated with nosocomial transmission risk. These risks are greatly compounded by multidrug-resistant disease. Screening and diagnosis of TB in this clinical setting is difficult. However, progress has been made in defining a high-sensitivity, standardized symptom screening tool that assesses a combination of symptoms, rather than relying on report of cough alone. Moreover, newly emerging diagnostic tools show great promise in providing more rapid diagnosis of TB, which is predominantly sputum smear–negative. These include culture-based systems, simplified versions of nucleic acid amplification tests (such as the Xpert MTB/RIF assay), and detection of lipoarabinomannan antigen in urine. In addition, new molecular diagnostics now permit rapid detection of drug resistance. Further development and implementation of these tools is vital to permit rapid and effective screening for TB in ART services, which is an essential component of patient care.

Voices from the frontline: counsellors' perspectives on TB/HIV collaborative activities in the Northwest Region, Cameroon

BACKGROUND

The overlapping epidemiology of tuberculosis (TB) and human immunodeficiency virus (HIV) infections prompted the World Health Organisation in 2004 to recommend collaboration between national TB and HIV programmes. The goal of this collaboration is to decrease the burden of both infections in the population. This policy was subsequently adopted by the national TB and HIV programmes in Cameroon with TB and HIV nurses/counsellors acting as frontline implementers of the collaborative activities in the 10 regions of the country.

METHODS

Qualitative research interviews were conducted with 30 nurses/counsellors in four approved treatment centres providing comprehensive TB and HIV/AIDS services in the Northwest region of Cameroon. The aim was to explore their experiences in counselling, in delivering joint TB and HIV services, and the constraints to effective collaboration between TB and HIV services. To complement the findings from the counsellors' interviews, as part of an emergent design, further interviews with 2 traditional healers and non-participant observations in two HIV support group meetings were conducted.

RESULTS

According to the respondents, counselling was regarded as a call to serve humanity irrespective of the reasons for choosing the profession. In addition, the counselling training and supervision received, and the skills acquired, have altogether contributed to build patients' trust in the healthcare system. Teamwork among healthcare workers and other key stakeholders in the community involved in TB/HIV prevention and control was used as a strategy to improve joint service delivery and patients' uptake of services. Several constraints to effective collaboration between TB and HIV services were identified, including shortage of human resources, infrastructure and drug supplies, poor patients' adherence to treatment and the influence of traditional healers who relentlessly dissuade patients from seeking mainstream medical care.

CONCLUSIONS

In order to achieve a sustainable collaboration between TB and HIV services, adequate planning, investment and strengthening of the health system including human resources, infrastructure and ensuring uninterrupted supplies of medicines are essential. A multidisciplinary approach to service delivery particularly focusing on harnessing the enormous potentials of traditional healers in TB/HIV prevention and control would also be indispensible.

Diagnostic accuracy of a low-cost, urine antigen, point-of-care screening assay for HIV-associated pulmonary tuberculosis before antiretroviral therapy: a descriptive study

Background

The diagnostic accuracy of sputum smear microscopy and routine chest radiology for HIV-associated tuberculosis is poor, and culture-based diagnosis is slow, expensive, and is unavailable in most resource-limited settings. We assessed the diagnostic accuracy of a urine antigen test Determine TB-LAM Ag (Determine TB-LAM; Alere, Waltham, MA, USA) for screening for HIV-associated pulmonary tuberculosis before antiretroviral therapy (ART).

Methods

In this descriptive study, consecutive adults referred to a community-based ART clinic in Gugulethu township, South Africa, were all screened for tuberculosis by obtaining sputum samples for fluorescence microscopy, automated liquid culture (gold-standard test), and Xpert MTB/RIF assays (Cepheid, Sunnyvale, CA, USA) and urine samples for the Clearview TB-ELISA (TB-ELISA; Alere, Waltham, MA, USA) and Determine TB-LAM test. Patients with Mycobacterium tuberculosis cultured from one or more sputum samples were defined as cases of tuberculosis. The diagnostic accuracy of Determine TB-LAM used alone or combined with sputum smear microscopy was compared with that of sputum culture and the Xpert MTB/RIF assay for all patients and subgroups of patients stratified by CD4 cell count.

Findings

Patients were recruited between March 12, 2010, and April 20, 2011. Of 602 patients enrolled, 542 were able to provide one or more sputum samples, and 94 had culture-positive tuberculosis (prevalence 17·4%, 95% CI 14·2–20·8). Complete results from all tests were available for 516 patients (median CD4 count, 169·5 cells per μL; IQR 100–233), including 85 culture-positive tuberculosis, 24 of whom (28·2%, 95% CI 19·0–39·0) had sputum smear-positive disease. Determine TB-LAM test strips provided results within 30 min. Agreement was very high between two independent readers of the test strips (κ=0·97) and between the test strips and TB-ELISA (κ=0·84). Determine TB-LAM had highest sensitivity at low CD4 cell counts: 66·7% (95% CI 41·0–86·7) at <50 cells per μL, 51·7% (32·5–70·6) at <100 cells per μL, and 39·0% (26·5–52·6) at <200 cells per μL; specificity was greater than 98% for all strata. When combined with smear microscopy (either test positive), sensitivity was 72·2% (95% CI 46·5–90·3) at CD4 counts less than 50 cells per μL, 65·5% (45·7–82·1) at less than 100 cells per μL, and 52·5% (39·1–65·7) at less than 200 cells per μL, which did not differ statistically from the sensitivities obtained by testing a single sputum sample with the Xpert MTB/RIF assay.

Interpretation

Determine TB-LAM is a simple, low-cost, alternative to existing diagnostic assays for tuberculosis screening in HIV-infected patients with very low CD4 cell counts and provides important incremental yield when combined with sputum smear microscopy.

Funding

Wellcome Trust.

Tuberculosis infection control in rural South Africa: survey of knowledge, attitude and practice in hospital staff

A baseline assessment of tuberculosis infection control (TB IC) knowledge, attitude and practice (KAP) was conducted among staff in a resource-limited rural South African hospital where nosocomially transmitted multi- and extensively drug-resistant (M/XDR) TB had been reported. Assessment consisted of anonymous questionnaires and direct observation during July-September 2007, soon after the report of M/XDR-TB. Data were obtained from 57 questionnaires and 10h of direct observation. While knowledge and attitudes were generally supportive of TB IC implementation, 49.1% of staff felt that the hospital did not care about them and/or was not working to prevent staff TB infections, and 42.9% were less willing to continue as a healthcare worker because of staff TB/MDR-TB/XDR-TB deaths. Practices were variable. The recent appointment of an IC officer and implementation of natural ventilation were strengths, but the facility lacked a TB IC policy, the patient TB screening process was inadequate, and 41.5% of respondents were unaware of their personal human immunodeficiency virus (HIV) status. Respondents reported a number of barriers to TB IC implementation such as concerns about the confidentiality of staff health information, the stigma of TB and HIV, inadequate resources, and patient non-compliance. Assessment of staff KAP provided useful data regarding deficits and barriers to TB IC, and helped to focus subsequent IC strategies. Given the critical importance of reducing nosocomial TB transmission, it is recommended that facilities should conduct simplified TB IC assessment, ensure the confidentiality of staff health information, address the stigma of TB/HIV, and implement multi-faceted TB IC facility and behavioural change interventions. Behavioural science methods have the potential to improve TB IC research and implementation.

Drug-resistant tuberculosis in sub-saharan Africa

Drug-resistant tuberculosis (DRTB) is an emerging infectious disease threat to sub-Saharan Africa (SSA), particularly in the regions hit hardest by the HIV epidemic. Numerous challenges face clinicians and public health officials tasked with combating DRTB in SSA. These include difficulties providing effective diagnosis, treatment, and prevention of this illness. Furthermore, combating DRTB requires addressing various legal and ethical complexities. A sustained commitment to investigating as well as implementing new diagnostic, therapeutic, and preventative interventions is essential to defeating this threat.