Screening, Treatment, and Transmission Control

1. Impact of BCG Vaccination Policies on TB Epidemiology

• Stopping universal BCG vaccination does not universally increase childhood TB cases.
• Only Slovakia saw a significant rise in childhood TB rates; other countries (Norway, France, UK) remained stable or declined. See also: https://idebeasiswa.com
• Migration patterns influenced TB rates, especially in France and Norway.
• Pulmonary TB and TB lymphadenitis were the most common forms; severe TB cases stayed below 4%.
• Discontinuation could raise TB burden in high vaccine efficacy regions, but selective vaccination is a viable alternative.
• Strong surveillance and targeted vaccination strategies are necessary.

2. Challenges in Pediatric TB Diagnosis and Care

• Diagnosing pediatric TB is difficult due to sample collection challenges.
• Alternative methods (stool, nasopharyngeal aspirates) offer similar sensitivity to induced sputum.
• Many children with TB symptoms remain undiagnosed due to limited diagnostic accessibility.
• Decentralizing TB services to district hospitals (DHs) is cost-effective in high-prevalence areas.
• Extending services to primary health centers (PHCs) is less feasible due to cost and efficiency concerns.
• DHs detect more TB cases due to better diagnostic tools and referral practices.

3. Innovations in TB Diagnosis and Treatment

• A new diagnostic tool is expected to accelerate pulmonary TB burden reduction.
• Most beneficial in areas with good TB care access but limited diagnostic sensitivity.
• Less impact in reference labs with high diagnostic accuracy.
• Could improve patient trust, reduce diagnosis delays, and minimize repeated healthcare visits.

4. TB Screening, Surveillance, and Transmission Control

• Screening and treating latent and asymptomatic TB infections significantly reduce transmission rates.
• The most effective approach combines vaccination, screening, and treatment.
• Study in Eastern Cape, South Africa, identified key TB surveillance challenges: Transport issues for community health workers (CHWs). Community distrust and resource disparities between rural and urban areas. Need for tailored TB surveillance interventions.

5. TB in High-Risk Populations: Loss to Follow-Up and Occupational Risk

• Study in Kenya found a 42.4% pre-treatment loss to follow-up (PTLFU) rate in pulmonary TB patients.
• Major risk factors: limited contact details and older age (≥55 years).
• Sex, HIV status, and prior TB treatment did not significantly affect PTLFU.
• Healthcare workers (HCWs) in Taiwan have a higher TB incidence than the general population.
• HCWs have better TB outcomes due to early diagnosis, treatment, and the "healthy worker effect."

References:

1. Kobayashi, S., Yoshiyama, T., Uchimura, K., Hamaguchi, Y. and Kato, S., 2021. Epidemiology of childhood tuberculosis after ceasing universal Bacillus Calmette–Guérin vaccination. Scientific Reports, 11(1), p.15902.
2. Fu, H., Lin, H.H., Hallett, T.B. and Arinaminpathy, N., 2018. Modelling the effect of discontinuing universal Bacillus Calmette-Guérin vaccination in an intermediate tuberculosis burden setting. Vaccine, 36(39), pp.5902-5909.
3. d'Elbée, M., Harker, M., Mafirakureva, N., Nanfuka, M., Nguyet, M.H.T.N., Taguebue, J.V., Moh, R., Khosa, C., Mustapha, A., Mwanga-Amumpere, J. and Borand, L., 2024. Cost-effectiveness and budget impact of decentralising childhood tuberculosis diagnosis in six high tuberculosis incidence countries: a mathematical modelling study. EClinicalMedicine, 70, p.102528.
4. Lin, H.H., Dowdy, D., Dye, C., Murray, M. and Cohen, T., 2012. The impact of new tuberculosis diagnostics on transmission: why context matters. Bulletin of the World Health Organization, 90, pp.739-747.
5. Mulaku, M.N., Ochodo, E., Young, T. and Steingart, K.R., 2024. Pre-treatment loss to follow-up in adults with pulmonary TB in Kenya. Public Health Action, 14(1), pp.34-39.
6. Kirimi, E.M., Muthuri, G.G., Ngari, C.G. and Karanja, S., 2024. A Model for the Propagation and Control of Pulmonary Tuberculosis Disease in Kenya. Discrete Dynamics in Nature and Society, 2024(1), p.5883142.
7. Ajudua, F.I. and Mash, R.J., 2024. Implementing active surveillance for TB: A descriptive survey of healthcare workers in the Eastern Cape, South Africa. African Journal of Primary Health Care & Family Medicine, 16(1), p.4217. See also: https://tbreadingnotes.blogspot.com/2024/07/tuberculosis-in-healthcare-workers.html
8. Pan S-C, Chen Y-C, Wang J-Y, Sheng W-H, Lin H-H, Fang C-T, et al. (2015) Tuberculosis in Healthcare Workers: A Matched Cohort Study in Taiwan. PLoS ONE 10(12): e0145047.

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Social Determinants and Global TB Control

1. Air Pollution and TB Risk

• Household air pollutants (HAP), particularly PM2.5 and CO, from kerosene lighting and biomass cooking, elevate TB risk.
• PM2.5 exposure in study participants averaged 170 µg/m³, far exceeding WHO’s guideline of 25 µg/m³.
• Area PM2.5 significantly contributes to TB risk (OR 6.74), with kerosene lighting associated with increased odds (OR 3.73).
• PM exposure disrupts immune function and enhances M. tuberculosis growth, while NO2 exposure weakens host defenses.
• Reduction of air pollution is essential for TB prevention and control.

Intervention Plan: Implement a community-based program to distribute clean energy solutions (e.g., solar lighting and LPG stoves) to replace kerosene and biomass fuel. This program would also include education on proper ventilation and regular HAP monitoring to reduce PM2.5 exposure.

See also: Scholarships to Australia

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2. Nutrition and TB Dynamics

• Undernutrition is the leading risk factor for TB, impairing immunity and increasing susceptibility.
• Nutritional interventions reduce TB incidence and mortality, with a projected 23.6% reduction in TB incidence and a 35.5% decrease in mortality in high-risk populations when scaled.
• Historical case studies highlight the impact of improved nutrition on reducing TB rates during crises.
• Vitamin supplementation shows potential for TB prevention, particularly among high-risk family contacts.

Intervention Plan: Integrate nutritional support into TB care programs by providing monthly nutrient-rich food packages and micronutrient supplements to TB patients and their households. Monitor and adjust diets based on local nutritional deficiencies.

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3. Healthcare Systems and Diagnostic Gaps

• High-burden countries struggle with underinvestment, limited access to rapid molecular diagnostics, and case detection challenges.
• Only 38% of TB cases were tested using WHO-recommended diagnostics in 2021.
• Innovations like AI-assisted x-rays, oral swabs, and urine antigen tests face adoption barriers due to cost and infrastructure limitations.

Intervention Plan: Launch a mobile diagnostic initiative using AI-assisted chest x-rays and portable molecular diagnostic tools in underserved regions. Subsidize costs through public-private partnerships to improve early detection and reduce delays in TB diagnosis.

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4. Comorbidities and TB Risk

• TB-DM patients face higher metabolic disturbances, nutritional deficits, and cardiovascular risks.
• Poor glycemic control (HbA1c >10%) and vitamin D deficiency (73.68% in TB-DM group) exacerbate complications.
• Dialysis patients face elevated TB risks due to weakened immunity from oxidative stress and uremic toxins.

Intervention Plan: Develop a TB-DM management protocol that integrates glycemic control, regular vitamin D supplementation, and nutritional monitoring into existing healthcare services. Screen dialysis patients for TB risk and provide targeted prophylaxis.

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5. Social Determinants and Global TB Control

• Poverty, overcrowding, and poor living conditions are drivers of TB prevalence.
• Achieving the SDGs for TB requires sustained funding, equitable healthcare access, and addressing social determinants.
• Rapid mortality declines in some sub-Saharan African countries highlight the potential of focused interventions.

Intervention Plan: Introduce a conditional cash transfer program for TB-affected households to improve living conditions, reduce overcrowding, and provide access to healthcare. Combine this with public awareness campaigns to address stigma and encourage treatment adherence.

References:

1. Jagger, P., McCord, R., Gallerani, A., Hoffman, I., Jumbe, C., Pedit, J., Phiri, S., Krysiak, R. and Maleta, K., 2024. Household air pollution exposure and risk of tuberculosis: a case–control study of women in Lilongwe, Malawi. BMJ Public Health, 2(1).
2. Lu, J.W., Mao, J.J., Zhang, R.R., Li, C.H., Sun, Y., Xu, W.Q., Zhuang, X., Zhang, B. and Qin, G., 2023. Association between long-term exposure to ambient air pollutants and the risk of tuberculosis: A time-series study in Nantong, China. Heliyon, 9(6).
3. Reid, M., Agbassi, Y.J.P., Arinaminpathy, N., Bercasio, A., Bhargava, A., Bhargava, M., Bloom, A., Cattamanchi, A., Chaisson, R., Chin, D. and Churchyard, G., 2023. Scientific advances and the end of tuberculosis: a report from the Lancet Commission on Tuberculosis. The Lancet, 402(10411), pp.1473-1498.
4. Furin, J., Cox, H., & Pai, M. (2019). Tuberculosis. Lancet (London, England), 393(10181), 1642–1656.
5. Mandal, S., Bhatia, V., Bhargava, A., Rijal, S. and Arinaminpathy, N., 2024. The potential impact on tuberculosis of interventions to reduce undernutrition in the WHO South-East Asian Region: a modelling analysis. The Lancet Regional Health-Southeast Asia, p.100423.
6. Cegielski, J.P. and McMurray, D.N., 2004. The relationship between malnutrition and tuberculosis: evidence from studies in humans and experimental animals. The international journal of tuberculosis and lung disease, 8(3), pp.286-298.
7. Shu, C.C., Hsu, C.L., Wei, Y.F., Lee, C.Y., Liou, H.H., Wu, V.C., Yang, F.J., Lin, H.H., Wang, J.Y., Chen, J.S. and Yu, C.J., 2016. Risk of tuberculosis among patients on dialysis: the predictive value of serial interferon-gamma release assay. Medicine, 95(22), p.e3813.
8. Patel, D.G., Baral, T., Kurian, S.J., Malakapogu, P., Saravu, K. and Miraj, S.S., 2024. Nutritional status in patients with tuberculosis and diabetes mellitus: A comparative observational study. Journal of Clinical Tuberculosis and Other Mycobacterial Diseases, 35, p.100428.

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NCD Screening in TB Contact Tracing

Diabetes and TB Incidence

• Korea's National Health Insurance Data Analysis: Diabetic individuals exhibit a 48% increased risk of tuberculosis (TB).Risk escalates with diabetes duration; over 5 years of diabetes corresponds to a 57% heightened TB risk. Stronger diabetes-TB links observed in men and younger adults. Newly diagnosed diabetics with high fasting plasma glucose (FPG) levels face a 79% greater TB risk. See also: Lin TB Lab

TB Treatment Outcomes

• Study from Taiwan NHIRD (2002-2013): Post-TB treatment phases see elevated risks of diabetes, acute myocardial infarction (AMI), and stroke, especially with treatment durations of 7-12 months. Risks are influenced by age, gender, and pre-existing non-communicable diseases (NCDs).Emphasizes the need for vigilant monitoring for NCDs following TB treatment.

Latent TB in Type 1 Diabetes Patients

• Cross-Sectional Study in Dar es Salaam: 14.9% prevalence of latent TB among type 1 diabetes mellitus (T1DM) patients, with variations across developmental stages. Significant correlation found between uncontrolled HbA1c levels and higher latent TB prevalence.

Observational Challenges and Mendelian Randomization Insights

• Challenges in Diabetes and PTB Relationship Studies: Issues include reverse causality, confounding factors, and type differentiation (T1DM vs. T2DM).Poor glycemic control linked to increased TB risk; metabolic disturbances in T1DM enhance susceptibility to PTB.
• Mendelian Randomization Findings: Genetic studies suggest a link between T1DM and PTB, with correlations to higher HDL-C levels but no direct causal relationships with other T1DM-related traits.

TB and Non-Communicable Diseases in Myanmar

• Yangon, Myanmar Cross-Sectional Study: TB patients often exhibit behavioral risk factors like smoking and drinking more frequently than general population. Nutritional disparities show TB patients more likely to be underweight; significantly lower incidence of overweight/obesity. Higher diabetes prevalence among TB patients, with implications for integrated screening of NCDs during TB contact tracing.

Integration of NCD Screening in TB Contact Tracing

• Efficiency and Cost-Effectiveness: Incorporating NCD screening during TB contact investigations can identify undiagnosed conditions, improving early intervention and management. Highlights the necessity for community-wide screening initiatives, particularly for diabetes, to address the dual burden of TB and NCDs.

References:

1. Yoo JE, Kim D, Han K, Rhee SY, Shin DW, Lee H. Diabetes status and association with risk of tuberculosis among Korean adults. JAMA network open. 2021 Sep 1;4(9):e2126099.
2. Salindri, A.D., Wang, J.Y., Lin, H.H. and Magee, M.J., 2019. Post-tuberculosis incidence of diabetes, myocardial infarction, and stroke: retrospective cohort analysis of patients formerly treated for tuberculosis in Taiwan, 2002–2013. International Journal of Infectious Diseases, 84, pp.127-130.
3. Majaliwa, E.S., Muze, K., Godfrey, E., Byashalira, K., Mmbaga, B.T., Ramaiya, K. and Mfinanga, S.G., 2023. Latent tuberculosis in children and youth with type 1 diabetes mellitus in Dar es Salaam, Tanzania: a cross section survey. BMC Infectious Diseases, 23(1), p.740.
4. Jiang, Y., Zhang, W., Wei, M., Yin, D., Tang, Y., Jia, W., Wang, C., Guo, J., Li, A. and Gong, Y., 2024. Associations between type 1 diabetes and pulmonary tuberculosis: a bidirectional mendelian randomization study. Diabetology & Metabolic Syndrome, 16(1), pp.1-9.
5. Zayar, N.N., Chotipanvithayakul, R., Bjertness, E., Htet, A.S., Geater, A.F. and Chongsuvivatwong, V., 2023. Vulnerability of NCDs and Mediating Effect of Risk Behaviors Among Tuberculosis Patients and Their Household Contacts Compared to the General Population in the Yangon Region, Myanmar. International Journal of General Medicine, pp.5909-5920.
6. Hamada, Y., Lugendo, A., Ntshiqa, T., Kubeka, G., Lalashowi, J.M., Mwastaula, S., Ntshamane, K., Sabi, I., Wilson, S., Copas, A. and Velen, K., 2024. A pilot cross-sectional study of non-communicable diseases in TB household contacts. IJTLD OPEN, 1(4), pp.154-159.

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