Tuberculosis Control Strategies Research Articles

Molecular Characterization of Drug-Resistant Beijing Family Isolates of Mycobacterium Tuberculosis from Tianjin, China

Tuberculosis remains a severe public health issue, and the Beijing family of mycobacterium tuberculosis (M. tuberculosis) is widespread in East Asia, especially in some areas in China, like Beijing and Tianjin. This study aimed at determining the mutation patterns of drug-resistant Beijing strains of M. tuberculosis isolated from Tianjin, China. A total of 822 M. tuberculosis isolates were screened for drug resistance by an absolute concentration method and the genotype was identified by PCR. 169 drug-resistant isolates of the Beijing family were analyzed for the potential mutations in the rpoB, katG, inhA promoter region and in rpsL, rrs and embB genes, which are associated with resistance to rifampin (RFP), isoniazid (INH), streptomycin (SM) and ethambutol (EMB) respectively by PCR and DNA sequencing. Fifty-eight out of 63 RFP-resistant isolates were found to carry the mutations within the 81-bp RFP resistance determining region (RRDR) of the rpoB gene and the most frequent mutations occurred at codon 531 (44.4%), 526 (28.6%), and 516 (7.9%) respectively. 16 mutation patterns affecting 12 different codons around the RRDR of rpoB were found. Of 116 INH-resistant isolates, 56 (48.3%) had the mutation of katG 315 (AGC-->ACC) (Ser-->Thr), 3 (2.6%) carried S315N (AGC-->AAC) and 27 (16.0%) had the mutation of inhA-15A-->T. 84 out of 122 SM-resistant isolates (68.9%) displayed mutations at the codons 43 or 88 with AAG-->AGG (Lys-->Arg) of the rpsL gene and 22 (18.0%) with the mutations at positions 513A-->C, 516C-->T or 905 A-->G in the rrs gene. Of 34 EMB-resistant isolates, 6 had mutation with M306V (ATG-->GTG), 3 with M306I (ATG-->ATT), 1 with M306I (ATG-->ATA), 1 with D328Y (GAT-->TAT), 1 with V348L (GTC-->CTC), and 1 with G406S (GGC-->AGC) in the embB gene. These novel findings extended our understanding of resistance-related mutations in the Beijing strains of M. tuberculosis and may provide a scientific basis for development of new strategies for diagnosis and control of tuberculosis in China and other countries where Beijing strains are prevalent.

Mining and Risk of Tuberculosis in Sub-Saharan Africa

We estimated the relationship between mining and tuberculosis (TB) among countries in sub-Saharan Africa. We used multivariate regression to estimate the contribution of mining activity to TB incidence, prevalence, and mortality, as well as rates of TB among people living with HIV, with control for economic, health system, and population confounders. Mining production was associated with higher population TB incidence rates (adjusted b = 0.093; 95% confidence interval [CI] = 0.067, 0.120; with an increase of mining production of 1 SD corresponding to about 33% higher TB incidence or 760,000 more incident cases), after adjustment for economic and population controls. Similar results were observed for TB prevalence and mortality, as well as with alternative measures of mining activity. Independent of HIV, there were significant associations between mining production and TB incidence in countries with high HIV prevalence (≥ 4% antenatal HIV prevalence; HIV-adjusted B = 0.066; 95% CI = 0.050, 0.082) and between log gold mining production and TB incidence in all studied countries (HIV-adjusted B = 0.053; 95% CI = 0.032, 0.073). Mining is a significant determinant of countrywide variation in TB among sub-Saharan African nations. Comprehensive TB control strategies should explicitly address the role of mining activity and environments in the epidemic.

The Population Dynamics and Control of Tuberculosis

More than 36 million patients have been successfully treated via the World Health Organization's strategy for tuberculosis (TB) control since 1995. Despite predictions of a decline in global incidence, the number of new cases continues to grow, approaching 10 million in 2010. Here we review the changing relationship between the causative agent, Mycobacterium tuberculosis, and its human host and examine a range of factors that could explain the persistence of TB. Although there are ways to reduce susceptibility to infection and disease, and a high-efficacy vaccine would boost TB prevention, early diagnosis and drug treatment to interrupt transmission remain the top priorities for control. Whatever the technology used, success depends critically on the social, institutional, and epidemiological context in which it is applied.

On the way to shortening tuberculosis treatments: clinical trials of the Unitat d' Investagació en Tuberculosi de Barcelona supported by the Centers for Disease Control and Prevention

New treatment guidelines are required to improve the tuberculosis control strategies that have been used for 30 years. Seven centers of the Barcelona Tuberculosis Research Unit (BTRU) (Unitat d'Investigacio en Tuberculosi de Barcelona) are collaborating with the Division of Tuberculosis Elimination of the United States Centers for Disease Control and Prevention in a series of clinical trials on latent tuberculosis infection and tuberculosis disease. BTRU participation began in 2004 with Study 26, an evaluation of the efficacy and tolerability of rifapentine plus isoniazid administered once weekly for 3 months compared with the standard treatment for latent tuberculosis infection. The BTRU centers together enrolled 246 patients (3% of the total). General enrollment was completed in February, 2008. HIV-infected patient and child enrollment continues. Treatment with 12 doses instead of 270 doses is expected to be a clear success. However, the analysis will be completed in 2010. Study 28 (started in 2006), designed for the treatment of pulmonary tuberculosis, compared standard treatment with an experimental regimen substituting moxifloxacin for isoniazid. BTRU centers together enrolled 15 patients (3.5% of the total). The provisional results (presented at the 47th Interscience Conference on Antimicrobial Agents and Chemotherapy in Chicago, 2007) showed no difference between the sputum conversion rate of each regimen at week 8 of treatment. Study 29 is currently underway, in which rifapentine was introduced in the experimental regimen for active tuberculosis treatment.

Associations betweenMycobacterium tuberculosisStrains and Phenotypes

To inform development of tuberculosis (TB) control strategies, we characterized a total of 2,261 Mycobacterium tuberculosis complex isolates by using multiple phenotypic and molecular markers, including polymorphisms in repetitive sequences (spoligotyping and variable-number tandem repeats [VNTRs]) and large sequence and single-nucleotide polymorphisms. The Beijing family was strongly associated with multidrug resistance (p = 0.0001), and VNTR allelic variants showed strong associations with spoligotyping families: >or=5 copies at exact tandem repeat (ETR) A, >or=2 at mycobacterial interspersed repetitive unit 24, and >or=3 at ETR-B associated with the East African-Indian and M. bovis strains. All M. tuberculosis isolates were differentiated into 4 major lineages, and a maximum parsimony tree was constructed suggesting a more complex phylogeny for M. africanum. These findings can be used as a model of pathogen global diversity.

En el camino para acortar los tratamientos de la tuberculosis: los ensayos clínicos de la Unitat d'Investigació en la Tuberculosi de Barcelona impulsados por los Centres for Disease Control and Prevention

New treatment guidelines are required to improve the tuberculosis control strategies that have been used for 30 years. Seven centers of the Barcelona Tuberculosis Research Unit (BTRU) ( Unitat d'Investigació en Tuberculosi de Barcelona) are collaborating with the Division of Tuberculosis Elimination of the United States Centers for Disease Control and Prevention in a series of clinical trials on latent tuberculosis infection and tuberculosis disease. BTRU participation began in 2004 with Study 26, an evaluation of the efficacy and tolerability of rifapentine plus isoniazid administered once weekly for 3 months compared with the standard treatment for latent tuberculosis infection. The BTRU centers together enrolled 246 patients (3% of the total). General enrollment was completed in February, 2008. HIV-infected patient and child enrollment continues. Treatment with 12 doses instead of 270 doses is expected to be a clear success. However, the analysis will be completed in 2010. Study 28 (started in 2006), designed for the treatment of pulmonary tuberculosis, compared standard treatment with an experimental regimen substituting moxifloxacin for isoniazid. BTRU centers together enrolled 15 patients (3.5% of the total). The provisional results (presented at the 47th Interscience Conference on Antimicrobial Agents and Chemotherapy in Chicago, 2007) showed no difference between the sputum conversion rate of each regimen at week 8 of treatment. Study 29 is currently underway, in which rifapentine was introduced in the experimental regimen for active tuberculosis treatment.

Collaborative push to address TB crisis on mines.

After a century of failed tuberculosis control strategies on South Africa’s mines, and three major but ineffective enquiries and commissions, a government-led ‘TB in Mines Task Team’ is being set up to address the deepening HIV-driven crisis. This was revealed by Professor Gavin Churchyard, CEO of the Aurum Institute for Health Research, a not-for-profit public benefit organisation with roots in the mining industry. He was addressing the annual Investigators Meeting of the international Consortium to Respond Effectively to the AIDS/TB Epidemic (CREATE) in Cape Town in mid-October. Churchyard revealed that the HIV-fuelled TB epidemic, compounded by rising drug resistance, is now estimated at 3 500 per 100 000 mine workers, with 40% of all autopsies on men who die working on the mines revealing they had TB. Migration from rural areas throughout southern Africa to Gauteng and surrounding industrial areas to work in the mining, building and other dominant sectors is a major driver of the rampant TB epidemic. Dr Lindiwe Mvusi, Director of TB Control and Management in the national department of health and chairperson of the new ‘TB in Mines Task Team’, said because the pandemic embraced all South Africa’s neighbouring countries it demanded a regional, multi-stakeholder response. A third delegate at the meeting, an ‘anxious and concerned’ Deputy Health Minister, Dr Molefi Sefularo, said national TB prevalence had increased nearly threefold in the past decade. South Africa was now among the 10 worst performing countries on TB control, and Statistics SA had found that for every 100 deaths in 2006, 13 were from TB, making it the leading cause of death. Churchyard said less than 1% of all HIV-infected individuals in this country were accessing proven safe and effective isoniazid preventive TB therapy (IPT), a situation he calls ‘inexcusable’.

Patient-centred tuberculosis treatment delivery under programmatic conditions in Tanzania: a cohort study

BackgroundDirectly observed therapy (DOT) remains the cornerstone of the global tuberculosis (TB) control strategy. Tanzania, one of the 22 high-burden countries regarding TB, changed the first-line treatment regimen to contain rifampicin-containing fixed-dose combination for the full 6 months of treatment. As daily health facility-based DOT for this long period is not feasible for the patient, nor for the health system, Tanzania introduced patient centred treatment (PCT). PCT allows patients to choose for daily DOT at a health facility or at their home by a supporter of choice. The introduction of fixed dose combinations in the intensive and continuation phase made PCT feasible by eliminating the risk of selective drug taking by patients and reducing the number of tablets to be taken. The approach was tested in three districts with the objective to assess the effect of this strategy on TB treatment outcomesMethodsCohort analysis comparing patients treated under the PCT strategy (registered April-September 2006) with patients treated under health-facility-based DOT (registered April-September 2005). The primary outcome was the cure rate. Differences were assessed by calculating the risk ratios. Associations between characteristics of the supporters and treatment outcomes in the group of patients opting for home-based DOT were assessed through logistic regression.ResultsIn the PCT cohort there were 1208 patients and 1417 were included in the historic cohort. There was no significant difference in cure rates between the cohorts (risk ratio [RR]: 1.06; 95% confidence interval [CI]: 0.96-1.16). In the PCT cohort, significantly more patients had successful treatment (cure or treatment completed; RR: 1.10; 95%CI: 1.01-1.15). There were no characteristics of supporters that were associated with treatment outcome.ConclusionThe PCT approach showed similar cure rates and better treatment success rates compared to daily health-facility DOT. The results indicate that there are no specific prerequisites for the supporter chosen by the patient. The programmatic setting of the study lends strong support for scaling-up of TB treatment observation outside the health facility.

Childhood tuberculosis infection and disease: a spatial and temporal transmission analysis in a South African township.

Tuberculosis (TB) remains a leading cause of mortality and morbidity in South Africa. While adult TB results from both recent and past infection, childhood TB results from recent infection and reflects ongoing transmission despite current TB control strategies. A South African community with high rates of TB and HIV disease. A Geographic Information System was used to spatially and temporally define the relationships between TB exposure, infection and disease in children < 15 years of age with exposure to adult HIV-positive and HIV-negative TB disease on residential plots between 1997 and 2007. During the study period the annual adult TB notification rate increased from 629 to 2 106/100 000 and the rate in children aged < 15 years ranged between 664/100 000 and 1 044/100 000. The mean number of exposures to adult TB for TB-uninfected children, latently TB-infected children and TB cases were 5.1%, 5.4% and 33% per annum and the mean number of adult smear-positive cases per exposed child was 1.0, 1.6 and 1.9, respectively. Acquisition of TB infection was not associated with HIV status of the adult TB case to which the child was exposed, and 36% of child TB cases were diagnosed before the temporally closest adult case on their plot. Childhood infection and disease were quantitatively linked to infectious adult TB prevalence in an immediate social network. Childhood infection should be monitored in high-burden settings as a marker of ongoing TB transmission. Improved knowledge of township childhood and adult social networks could also facilitate targeted active case finding, which may provide an adjunct to currently failing TB control strategies.

An analysis of the costs and treatment success of collaborative arrangements among public and private providers for tuberculosis control in Indonesia

To identify the cost-effectiveness of collaborative arrangements among public and private providers to employ the Directly Observed Treatment short-course (DOTS) strategy for tuberculosis (TB) control in Indonesia. Three strategies were assessed: hospital out-patient diagnosis with referral to public health centres (PHCs) for treatment, hospital out-patient diagnosis and treatment, and private practitioner referral of suspects to PHCs. The outcome was the number of sputum smear positive TB cases successfully treated. Costs include direct costs to providers and patients. Uncertainty analysis was done for both costs and effectiveness data. The average cost per case successfully treated ranged from US$169 to $567 for different strategies. The cost per additional case successfully treated incremental to existing TB programmes ranged from US$152 to $982. In three of four provinces assessed, there was a clearly preferred strategy or strategies, although the preferred strategy differed by province; in one province a preferred strategy could not be identified. All strategies increased TB case finding, although attribution is tentative because of the study design. Neither collaboration among private practitioners nor among hospitals is clearly preferred based on cost-effectiveness. For hospitals, this study suggests that having hospitals refer patients to health centres is preferable over hospitals administering treatment.

Prevalence of tuberculosis, HIV and respiratory symptoms in two Zambian communities: implications for tuberculosis control in the era of HIV.

BackgroundThe Stop TB Partnership target for tuberculosis is to have reduced the prevalence of tuberculosis by 50% comparing 2015 to 1990. This target is challenging as few prevalence surveys have been conducted, especially in high burden tuberculosis and HIV countries. Current tuberculosis control strategies in high HIV prevalent settings are therefore based on limited epidemiological evidence and more evidence is needed from community-based surveys to inform improved policy formulation.Methods and Findings8044 adults were sampled from 2 sub-districts (wards) in Lusaka province, Zambia. Questionnaires were used to screen for symptoms, respiratory samples were obtained for culture and oral secretions collected for HIV testing. 79 individuals were found to have Mycobacterium tuberculosis in their sputum, giving an adjusted overall prevalence of tuberculosis of 870/100,000 (95% CI 570–1160/100,000). The adjusted overall prevalence of HIV was 28.61% (95% CI 26.04–31.19). HIV- infection was significantly associated with prevalent tuberculosis (Adj OR 2.3, 95% CI 1.42–3.74) and the population attributable fraction of HIV for prevalent tuberculosis was 36%. Symptoms such as prolonged cough (adj OR 12.72, 95% CI 7.05–22.94) and fever (Adj OR 2.04, 95%CI 1.23–3.39), were associated with prevalent tuberculosis, but 8 (10%) individuals with prevalent tuberculosis denied having any symptoms at all and only 34 (43%) would have been classified as a TB suspect by current guidelines.ConclusionsUndiagnosed tuberculosis is a challenge for tuberculosis control and new approaches are needed if we are to reach international targets. Epidemiological studies can inform screening algorithms for both detection and prevention of active tuberculosis.

Respiratory infections in immunocompromised patients

Immunosuppressive states and therapies are becoming common in clinical practice. Recent advances and trends in bacterial, fungal, viral and parasitic pulmonary infections in immunosuppressed patients are described. Pulmonary infections can jeopardize the prognosis of immunosuppressed patients. The number of patients infected with multidrug-resistant bacteria or opportunistic pathogens like rapid-growing environmental mycobacteria, Strongyloides stercoralis or Rhodococcus equi is increasing with the increased numbers of immunosuppressed patients due to HIV/AIDS and the potent immunosuppressive therapies used in solid-organ and haematopoietic transplantations, cancer and systemic illnesses. The slow development of more effective antibiotics underlines the necessity of preventive measures, development of rapid detection tests for pathogens and appropriate treatment regimens to avoid development of further resistance. Adequate prophylaxis, clinical suspicion, microbiological and molecular investigations, drug susceptibility-based antibiotic treatment and new drug development are strategies required to face up to the challenge of pulmonary infections in immunodepressed patients.

Drivers of tuberculosis epidemics: The role of risk factors and social determinants

The main thrust of the World Health Organization's global tuberculosis (TB) control strategy is to ensure effective and equitable delivery of quality assured diagnosis and treatment of TB. Options for including preventive efforts have not yet been fully considered. This paper presents a narrative review of the historical and recent progress in TB control and the role of TB risk factors and social determinants. The review was conducted with a view to assess the prospects of effectively controlling TB under the current strategy, and the potential to increase epidemiological impact through additional preventive interventions. The review suggests that, while the current strategy is effective in curing patients and saving lives, the epidemiological impact has so far been less than predicted. In order to reach long-term epidemiological targets for global TB control, additional interventions to reduce peoples' vulnerability for TB may therefore be required. Risk factors that seem to be of importance at the population level include poor living and working conditions associated with high risk of TB transmission, and factors that impair the host's defence against TB infection and disease, such as HIV infection, malnutrition, smoking, diabetes, alcohol abuse, and indoor air pollution. Preventive interventions may target these factors directly or via their underlying social determinants. The identification of risk groups also helps to target strategies for early detection of people in need of TB treatment. More research is needed on the suitability, feasibility and cost-effectiveness of these intervention options.

General physicians' knowledge of tuberculosis control and treatment with DOTS strategy

Purpose: Turberculosis has a long history and it is still fatal in the third millennium. Since 1993, the Directly Observed Therapy Short-Course (DOTS) strategy has been approved by the WHO as a global strategy for tuberculosis treatment and control. This research was undertaken to assess the general physicians' (GPs) knowledge of tuberculosis control and treatment using DOTS strategy and to evaluate the necessity for its insertion in the medical schools' curriculum. Material & Method: 1500 questionnaires were distributed to GPs at national conferences and continuing medical education sessions in tuberculosis and infections diseases. The questionnaires included questions about demographic information, general knowledge about DOTS, implementation of DOTS and problems related to its implementation. All data, were analyzed with an SPSS package, using the Chi-square rest. Findings: Out of the 486 GPs who responded to the questionnaires, 34.5% knew what DOTS stood for, and 43.8% were familiar with the definition of DOTS. In clinical teaching course, 10.2% had become familiar with DOTS in medical schools and 56.6%, through the health care system. 69% of the trained GPs and 14% of the untrained GPs answered the questions correctly. (P=0.001). about 21% of the GPs were involved in the implementation of DOTS. Among the GPS who were involved in implementing DOTS, 82% gave correct answers. From among the GPs who were not involved in implementing DOTS. 33% had correct answers to the questions (P=0.001). Conclusion: According to the results of this research, GPs have little knowledge of GPs strategy. Its entry into the medical curriculum is therefore essential. Key words: DOTS, TUBERCULOSIS CONTROL, GPs ' KNOWLDEDGE

Comparative study of the factors in tuberculosis treatment between immigrant workers and local residents in Shenzhen

To study the factors affecting the management and treatment of immigrant workers with tuberculosis, to determine the most effective measures and to provide an academic basis for tuberculosis control and prevention strategies targeting the immigrant population. A self-designed questionnaire was administered to 1364 immigrant workers with tuberculosis (study group) and 436 local residents (control group) with tuberculosis. Whether a patient's tuberculosis status was discovered or not was related to the medical facilities initially visited, job mobility, and the individual worker's economic condition. The percentage of cases discovered was relatively low among those who made their first visit to a private clinic (39.0%), and 58.4% (796) of immigrant workers delayed their first consultation mainly due to neglecting symptoms (55.9%, 445), subjective perception of symptoms being not severe enough (19.3%, 154) to visit a physician and the inconvenience of visiting a hospital because of its being far away from home (15.8%, 47). As comparing immigrant workers with local residents, the differences of the delay reason between the two groups were statistically significant (chi(2) = 21.49, P < 0.01). And 39.9% (544) of immigrant workers and 49.1% (214) of local residents had had late confirmation. The differences of the delay reasons between the two groups were insignificant (chi(2) = 7.31, P = 0.293). And 17.6% (240) patients of immigrant workers and 13.1% (57) patients of local residents did not keep to their drug regimens in a timely fashion. The differences of the reasons between the two groups were insignificant (chi(2) = 6.66, P > 0.05). And 77.5% (1057) of immigrant workers and 31.8% (138) of local residents were considered that taking medicine in supervision spot might have impact on their lives and work. The differences of the reasons between the two groups were significant (chi(2) = 9.71, P < 0.05). All 79.2% (1080) of immigrant workers and 63.3% (276) of local residents did not obtain medicine according to prescriptions. The differences of reasons between the two groups were statistically significant (chi(2) = 24.84, P < 0.01). And 51.2% (699) of immigrant workers and 46.1% (201) of the registered population did not follow up with doctors' directions for lab tests. The differences of the reasons between the two groups were insignificant (chi(2) = 3.26, P > 0.05). The influential factors in tuberculosis management and treatment were complex. Prevention strategies should focus on health education and promotion activities to improve awareness in seeking medical services. Also, developing and standardizing reference mechanisms for patients, and alleviating the economic burden of the workers will be critical to reduce the tuberculosis incidence.

Tuberculosis and patient gender: An analysis and its implications in tuberculosis control

Objective:To analyze the profile of pulmonary tuberculosis patients with respect to gender and its implications in tuberculosis control. Setting: DOTS center at a tertiary, teaching hospital in South India.Materials and Methods:A retrospective study was undertaken by screening medical records of 446 patients with pulmonary tuberculosis. Data studied included age, gender, and sputum smear status. Patients with comorbid conditions were excluded. No other data were considered.Results:The male to female ratio in patients of pulmonary tuberculosis was 2:1, which was also maintained when smear positive and smear negative were studied separately. The ratio of smear positive to smear negative patients was statistically significant at 4.4:1. A large proportion of patients (65–68%) were in the young and reproductive age group. Approximately, one-fifth patients were in the geriatric age group.Conclusion:The observation that two-thirds of all female smear-positive patients were found in the young and reproductive age group has strong implications in tuberculosis control strategies because of higher chances of mother to child transmission and higher probability of complications because of attendant antenatal and postnatal morbidity. Geriatric patients comprise another significant group because of higher chances of default, complications, inconvenience, and existence of other comorbid conditions.

High Incidence of Tuberculosis among HIV‐Infected Infants: Evidence from a South African Population‐Based Study Highlights the Need for Improved Tuberculosis Control Strategies

There are limited population-based estimates of tuberculosis incidence among human immunodeficiency virus (HIV)-infected and HIV-uninfected infants aged < or =12 months. We aimed to estimate the population-based incidence of culture-confirmed tuberculosis among HIV-infected and HIV-uninfected infants in the Western Cape Province, South Africa. The incidences of pulmonary, extrapulmonary, and disseminated tuberculosis were estimated over a 3-year period (2004-2006) with use of prospective representative hospital surveillance data of the annual number of culture-confirmed tuberculosis cases among infants. The total number of HIV-infected and HIV-uninfected infants was calculated using population-based estimates of the total number of live infants and the annual maternal HIV prevalence and vertical HIV transmission rates. There were 245 infants with culture-confirmed tuberculosis. The overall incidences of tuberculosis were 1596 cases per 100,000 population among HIV-infected infants (95% confidence interval [CI], 1151-2132 cases per 100,000 population) and 65.9 cases per 100,000 population among HIV-uninfected infants (95% CI, 56-75 cases per 100,000 population). The relative risk of culture-confirmed tuberculosis among HIV-infected infants was 24.2 (95% CI, 17-34). The incidences of disseminated tuberculosis were 240.9 cases per 100,000 population (95% CI, 89-433 cases per 100,000 population) among HIV-infected infants and 14.1 cases per 100,000 population (95% CI, 10-18 cases per 100,000 population) among HIV-uninfected infants (relative risk, 17.1; 95% CI, 6-34). This study indicates the magnitude of the tuberculosis disease burden among HIV-infected infants and provides population-based comparative incidence rates of tuberculosis among HIV-infected infants. This high risk of tuberculosis among HIV-infected infants is of great concern and may be attributable to an increased risk of tuberculosis exposure, increased immune-mediated tuberculosis susceptibility, and/or possible limited protective effect of bacille Calmette-Guérin vaccination. Improved tuberculosis control strategies, including maternal tuberculosis screening, contact tracing of tuberculosis-exposed infants coupled with preventive chemotherapy, and effective vaccine strategies, are needed for infants in settings where HIV infection and tuberculosis are highly endemic.

Reforming tuberculosis control in Ukraine: results of pilot projects and implications for the national scale-up of DOTS

The period of economic transition has had severe consequences for health and health systems in Ukraine. The tuberculosis (TB) situation illustrates this. The strategy recommended by the World Health Organization (WHO) for TB, directly observed treatment short-course (DOTS), has the potential to provide real improvements in TB services, forming the basis of the response to the growing epidemic. In 2002, Ukraine, financially supported by USAID and the European Community (EC), began to introduce DOTS through pilot projects in Mariupol and Kyiv City. The aim of this study is to assess the feasibility, effectiveness, health service cost, patient cost, and the cost-effectiveness of these pilots, in order to inform the national scale-up of DOTS. The study finds that DOTS is feasible and has the potential to be both effective and cost-effective in Ukraine. Following this study, Ukraine adopted DOTS as a national TB control strategy in 2005. However, the pilots also found that there are several evidence-related concerns and perverse economic incentives to both providers and patients that will need to be addressed if national scale-up is to be successful. These include concerns related to the treatment of MDR-TB, economic benefits to some patients to remain hospitalized, and payments to providers and health facilities that support current practices. These will need to be addressed if Ukraine is to develop an effective response to its emerging TB epidemic.

Linking TB and the Environment: An Overlooked Mitigation Strategy

One of the world’s leading killers, tuberculosis (TB) is nearly as old as humanity itself; fossilized evidence of this lethal infection has been found in a Homo erectus skeleton half a million years old. But look to a modern hospital in a developed country, and you’d be hard pressed to find more than a few cases. Historically, TB is a disease of the poor. Most of the 2–3 million people who die of the disease every year come from the developing world or from poor, urban neighborhoods in wealthier nations. For centuries, TB has been linked anecdotally with environmental risk factors that go hand-in-hand with poverty: indoor air pollution, tobacco smoke, malnutrition, overcrowded living conditions, and excessive alcohol use. Now scientists are presenting convincing evidence to back these associations, leading some TB experts to argue that control programs must confront underlying risk factors to limit the spread of the disease. According to the World Health Organization (WHO), more than 9 million new cases of TB are diagnosed annually, 55% of them in Asia and 31% in Africa, placing TB second only to HIV/AIDS in terms of the global burden of infectious disease. TB control strategies adopted by the WHO and other organizations emphasize clinical solutions in the form of drugs, vaccines, and access to health care. But despite the success of these programs, TB incidence and mortality aren’t falling rapidly enough to meet WHO targets, and in some areas, particularly in parts of Asia and throughout sub-Saharan Africa, they continue to climb. “Better treatment is essential, but if we want to affect longer-term trends in the epidemic we will also have to deal with risk factors,” asserts Eva Rehfuess, a scientist with the WHO Department of Public Health and Environment. “But doing that won’t be easy. Social and environmental interventions aren’t usually delivered or funded by the health sector, so that means we all have to work with other sectors, in particular housing, energy, and education, to move them forward.” Emerging evidence suggests such interventions could yield big benefits. In a report published online 3 October 2008 ahead of print in The Lancet, Majid Ezzati and colleagues at the Harvard School of Public Health predict that by 2033 TB incidence rates in parts of China could be 14–52% lower if tobacco smoking and indoor air pollution from traditional cooking stoves are eliminated. These reductions assume that 80% of the population already has access to optimal treatments for TB; the benefits would be even greater among those without such access, says Ezzati, an associate professor of global health and environmental health.

Comparative field evaluation of two rapid immunochromatographic tests for the diagnosis of bovine tuberculosis in African buffaloes ( Syncerus caffer)

Panels of sera from African buffalo with confirmed bovine tuberculosis and from known uninfected controls were used to evaluate the performance of two commercial rapid chromatographic immunoassays (A and B) for the detection of antibodies to Mycobacterium bovis. The sensitivity was 33% and 23%, respectively, while the specificity was determined at 90% and 94%, respectively. Overall the performance of both diagnostic tests under field conditions was not found sufficiently high to support their use in bovine tuberculosis management and control strategies in South African game reserves.