“Rapid-Impact Interventions”: How a Policy of Integrated Control for Africa's Neglected Tropical Diseases Could Benefit the Poor

Controlling seven tropical infections in Africa would cost just 40 cents per person per year, and would permanently benefit hundreds of millions of people

Indoor solid fuel use and tuberculosis in China: a matched case-control study

<p>Abstract</p> <p>Background</p> <p>China ranks second among the 22 high burden countries for tuberculosis. A modeling exercise showed that reduction of indoor air pollution could help advance tuberculosis control in China. However, the association between indoor air pollution and tuberculosis is not yet well established. A case control study was conducted in Anhui, China to investigate whether use of solid fuel is associated with tuberculosis.</p> <p>Methods</p> <p>Cases were new sputum smear positive tuberculosis patients. Two controls were selected from the neighborhood of each case matched by age and sex using a pre-determined procedure. A questionnaire containing demographic information, smoking habits and use of solid fuel for cooking or heating was used for interview. Solid fuel (coal and biomass) included coal/lignite, charcoal, wood, straw/shrubs/grass, animal dung, and agricultural crop residue. A household that used solid fuel either for cooking and (/or) heating was classified as exposure to combustion of solid fuel (indoor air pollution). Odds ratios and their corresponding 95% confidence limits for categorical variables were determined by Mantel-Haenszel estimate and multivariate conditional logistic regression.</p> <p>Results</p> <p>There were 202 new smear positive tuberculosis cases and 404 neighborhood controls enrolled in this study. The proportion of participants who used solid fuels for cooking was high (73.8% among cases and 72.5% among controls). The majority reported using a griddle stove (85.2% among cases and 86.7% among controls), had smoke removed by a hood or chimney (92.0% among cases and 92.8% among controls), and cooked in a separate room (24.8% among cases and 28.0% among controls) or a separate building (67.8% among cases and 67.6% among controls). Neither using solid fuel for cooking (odds ratio (OR) 1.08, 95% CI 0.62-1.87) nor using solid fuel for heating (OR 1.04, 95% CI 0.54-2.02) was significantly associated with tuberculosis. Determinants significantly associated with tuberculosis were household tuberculosis contact (adjusted OR, 27.23, 95% CI 8.19-90.58) and ever smoking tobacco (adjusted OR 1.64, 96% CI 1.01-2.66).</p> <p>Conclusion</p> <p>In a population where the majority had proper ventilation in cooking places, the association between use of solid fuel for cooking or for heating and tuberculosis was not statistically significant.</p

Evaluation of tuberculosis diagnostics: establishing an evidence base around the public health impact.

The limitations of existing tuberculosis diagnostic tools are significantly hampering tuberculosis control efforts, most noticeably in areas with high prevalence of human immunodeficiency virus (HIV) infection and antituberculosis drug resistance. However, renewed global interest in tuberculosis research has begun to bear fruit, with several new diagnostic technologies progressing through the development pipeline. There are significant challenges in building a sound evidence base to inform public health policies because most diagnostic research focuses on the accuracy of individual tests, with often significant limitations in the design, conduct, and reporting of diagnostic accuracy studies. Diagnostic accuracy studies may not be appropriate to guide public health policies, and clinical trials may increasingly be required to determine the incremental value and cost-effectiveness of new tools. The urgent need for new diagnostics should not distract from pursuing rigorous scientific evaluation focused on public health impact

The cost effectiveness of Nucleic Acid Amplification Techniques for the diagnosis of tuberculosis.

BACKGROUND: There is wide variation in the techniques deployed to diagnose tuberculosis in the UK, with little agreement on which tools or strategies are cost effective. This analysis therefore comprehensively evaluated the cost effectiveness of currently available diagnostic strategies for routine diagnosis of TB in the NHS. METHODS: The analysis compared strategies consisting of Nucleic Acid Amplification Techniques, culture and microscopy. A decision tree was used to estimate costs and Quality-Adjusted Life Years (QALYs) from a UK health service perspective. The sensitivity and specificity of each test determined the true and false positive and negative results in patients suspected of having active tuberculosis. These results led to either early, correct diagnosis or delayed diagnosis and the associated costs and QALYs. The presence of active tuberculosis combined with the side effects of treatment was associated with reduction in quality of life. Costs included were test costs, drug costs and the management of tuberculosis. Drug costs were based on generic UK list prices. Uncertainty in the model was explored through probabilistic and deterministic sensitivity analyses. RESULTS/CONCLUSIONS: The cost effective strategy at threshold of £20,000 per QALY was a strategy using only sputum microscopy and culture routinely, meaning Nucleic Acid Amplification Techniques are not cost effective at baseline. When the prevalence of tuberculosis was increased, however, nucleic acid amplification became cost effective at the same threshold. Aside from the prevalence, the results were shown to be robust. At low tuberculosis prevalence, Nucleic Acid Amplification Techniques may not be cost effective but their potential in higher prevalence situations is considerable

A Bayesian approach to understanding gender differences in tuberculosis disease burden

Globally, men have a higher epidemiological burden of tuberculosis (incidence, prevalence, mortality) than women, possibly due to differences in disease incidence, treatment initiation, self-cure and/or untreated-tuberculosis mortality rates. Using a simple, gender-stratified compartmental model, we employed a Bayesian approach to explore which factors most likely explain men's higher burden. We applied the model to smear-positive pulmonary tuberculosis in Viet Nam (2006-07) and Malawi (2013-14). Posterior estimates were consistent with gender-specific prevalence and notifications in both countries. Results supported higher incidence in men and showed that both genders faced longer durations of untreated disease than estimated by self-reports. Prior untreated disease durations were revised upwards 8- to 24-fold, to 2.2 (95% credible interval: 1.7, 2.9) and 2.8 (1.8, 4.1) years for men in Viet Nam and Malawi, respectively, approximately a year longer than for women in each country. Results imply that substantial gender differences in tuberculosis burden are almost solely attributable to men's disadvantages in disease incidence and untreated disease duration. The latter, for which self-reports provide a poor proxy, implies inadequate coverage of case finding strategies. These results highlight an urgent need for better understanding of gender-specific barriers faced by men and support the systematic targeting of men for screening