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Background Globally, the number of small-scale miners (SSM) is estimated to be more than 25 million, but it supports the livelihoods of around 100 million individuals. In Tanzania, the number of SSM has increased from an estimated 150,000 in 1987 to ~1.5 million in 2017. The miners are at a high risk of occupational-related health challenges. The study aimed to assess the concentrations of respirable crystalline silica (RCS) and radon among the tanzanite mining communities in Simanjiro District, Tanzania. Methods We carried out a cross-sectional study involving the Mererani mines in Tanzania. These are underground mines comprised of informally employed miners, i.e. SSM. Concentrations of RCS and radon gas were measured in 44 study units, i.e. 22 mining pits and within 22 houses in the general community, e.g. shops in the peri-mining community. A total of 132 respirable personal dust exposure samples (PDS), 3 from each of the study units were taken, but only 66 PDS from the mining pits were analysed, as this was the main interest of this study. Radon concentration was measured by continuous monitoring throughout the working shift (and overnight for residences) using AlphaGuard monitor. The medians and comparison to the reference values, OSHA USA PEL and WHO/IARC references, were done for RCS and radon, respectively, using SPSS Ver. 27.0.0). Results The median time-weighted average (TWA) concentration of the RCS in the mining pits was 1.23 mg/m3. Of all 66 personal dust samples from the mining pits, 65 (98.5%) had concentrations of RCS above the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 0.05 mg/m3. Mining pits had a median radon concentration of 169.50 bq/m3, which is above the World Health Organization (WHO)/International Commission on Radiation Protection (ICRP) recommended reference of 100.00 bq/m3 but not above the upper reference of 300.00 bq/m3, while the community buildings had a median radon concentration of 88.00 bq/m3. Overall, 9 (20.5%) and 17 (38.6%) radon measurements were above 300.00 bq/m3 and between 100.00 and 300.00 bq/m3 references, respectively. Specifically, in the mining pits, 9 (40.9%) test results were above 300.00 bq/m3, while none of the test results in the community was above 300.00 bq/m3. Conclusion The tanzanite SSM in Mererani we highly exposed to RCS, which increases the risk of pulmonary diseases, including silicosis, tuberculosis, and pulmonary malignancies. Immediate action by OSHA Tanzania should be enforcement of wearing respirators by all miners throughout the working hours. Health education programmes to the SSM must be strengthened and OSHA Tanzania should adopt the 0.05 mg/m3 PEL, and enforce other occupational health and safety measures, including regular use of dust suppression mechanisms (water spray and wet drilling) and monitoring of RCS exposures among SSM. Monitoring of radon exposure both in the mining pits and community buildings should be conducted, and mitigation measures should be implemented in areas that exceed the reference level of 100.00 bq/m3. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is among diseases of global health importance with Sub Saharan Africa (SSA) accounting for 25% of the global TB burden. TB prevalence among miners in SSA is estimated at 3,000–7,000/100,000, which is about 3 to 10-times higher than in the general population. The study's objective was to determine the prevalence of TB and associated risk factors among mining communities in Mererani, northern Tanzania. This was a cross-sectional study conducted from April 2019 to November 2021 involving current Small Scale Miners (SSM) and the General Community (GC). A total of 660 participants, 330 SSM and 330 GC were evaluated for the presence of TB. Data were analysed using Statistical Package for the Social Sciences (SPSS) database (IBM SPSS Statistics Version 27.0.0.0). Binary logistic regression (Generalized Linear Mixed Model) was used to determine the association between TB and independent predictors. Prevalence of TB was 7%, about 24-times higher than the national prevalence of 0.295%. Participants from the general community had higher prevalence of TB 7.9% than SSM (6.1%). Both for SSM and the GC, TB was found to be associated with: lower education level (aOR = 3.62, 95%CI = 1.16–11.28), previous lung disease (aOR = 4.30, 95%CI = 1.48–12.53) and having symptoms of TB (aOR = 3.24, 95%CI = 1.38–7.64). Specifically for the SSM, TB was found to be associated with Human Immunodeficiency Virus (HIV) infection (aOR = 8.28, 95%CI = 1.21–56.66). Though significant progress has been attained in the control of the TB epidemic in Tanzania, still hot spots with significantly high burden of TB exists, including miners. More importantly, populations surrounding the mining areas, are equally affected, and needs more engagement in the control of TB so as to realize the Global End TB targets of 2035. [ABSTRACT FROM AUTHOR]

Abstract Background Co-administration of anti-tuberculosis and antiretroviral therapy is often inevitable in high-burden countries where tuberculosis is the most common opportunistic infection associated with HIV/AIDS. Concurrent use of rifampicin and several antiretroviral drugs is complicated by pharmacokinetic drug-drug interaction. Method Pubmed and Google search following the key words tuberculosis, HIV, emtricitabine, tenofovir efavirenz, interaction were used to find relevant information on each drug of the fixed dose combination AtriplaR Results Information on generic name, trade name, pharmacokinetic parameter, metabolism and the pharmacokinetic interaction with Anti-TB drugs of emtricitabine, tenofovir, and efavirenz was obtained. Conclusion Fixed dose combination of emtricitabine/tenofovir/efavirenz (ATRIPLAR) which has been approved by Food and Drug Administration shows promising results as far as safety and efficacy is concerned in TB/HIV co-infection patients, hence can be considered effective and safe antiretroviral drug in TB/HIV management for adult and children above 3 years of age.

Background: Diabetes mellitus (DM) is associated with poor TB treatment outcome. Previous studies examining the effect of DM on TB drug concentrations yielded conflicting results. No studies have been conducted to date in an African population.Objectives: To compare exposure to TB drugs in Tanzanian TB patients with and without DM.Patients and Methods: A prospective pharmacokinetic study was performed among 20 diabetic and 20 non-diabetic Tanzanian TB patients during the intensive phase of TB treatment. Plasma pharmacokinetic parameters of isoniazid, rifampicin, pyrazinamide and ethambutol were compared using an independent-sample t-test on log-transformed data. Multiple linear regression analysis was performed to assess the effects of DM, gender, age, weight, HIV status and acetylator status on exposure to TB drugs.Results: A trend was shown for 25% lower total exposure (AUC0-24) to rifampicin among diabetics versus non-diabetics (29.9 versus 39.9 mg·h/L, P=0.052). The AUC0-24 and peak concentration (Cmax) of isoniazid were also lower in diabetic TB patients (5.4 versus 10.6 mg·h/L, P=0.015 and 1.6 versus 2.8 mg/L, P=0.013). Pyrazinamide AUC0-24 and Cmax values were non-significantly lower among diabetics (P=0.08 and 0.09). In multivariate analyses, DM remained an independent predictor of exposure to isoniazid and rifampicin, next to acetylator status for isoniazid.Conclusions: There is a need for individualized dosing of isoniazid and rifampicin based on plasma concentration measurements (therapeutic drug monitoring) and for clinical trials on higher doses of these TB drugs in patients with TB and DM. [ABSTRACT FROM AUTHOR]

Limited data among miners in Tanzania suggests prevalence of silicosis, obstructive lung disease and restrictive lung disease to be around 1.6%, 1.9% and 8.8% respectively. Our study aimed to determine the prevalence and factors associated with silicosis and impaired lung function among tanzanite mining community in northern Tanzania. We conducted a cross-sectional study, involving 330 miners and 330 peri-mining community members in Mererani mines. Silicosis was defined based on study participants' history of exposure to mining dust and digital chest radiological findings with reference to the 2011 ILO classification of pneumoconiosis. Impaired lung function was determined by spirometry using American Thoracic Society/European Respiratory Society recommended system 3. Association between evidence of silicosis/impaired lung function and presumed risk factors were determined using binary logistic regression analyses. The study found that 99/330 (30.0%) of miners had silicosis. Total of 65 (9.8%) participants had impaired lung function, of whom 29 (4.4%) had Chronic Obstructive Pulmonary Disease, 32 (4.8%) had restrictive lung disease and 4 (0.6%) had both obstructive and restrictive lung diseases. Unexpectedly, miners who have worked for more than 10years and those worked for 6 to 10 years had 64% (aOR 0.34, CI = 0.17-0.67, p = 0.002) and 48% (aOR 0.52, CI = 0.30-0.89, p = 0.018) lower odds of having silicosis respectively compared those worked for up to 5 years. Participants with more than 10 years of work duration had more than 3-times higher odds of impaired lung function compared to those who had worked for up to 5 years (aOR 3.11, CI = 1.53-6.34, p<0.002). We found a concerningly high prevalence of silicosis despite short durations of exposure to occupational silica dust. Immediate dust control measures including deployment of wet drilling, wearing of personal protective equipment and regular monitoring of dust exposure need to be enforced by the Occupational Safety and Health Authority-Tanzania., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Mbuya et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

East Africa has a high tuberculosis (TB) incidence and mortality, yet there are very limited data on exposure to TB drugs in patients from this region. We therefore determined the pharmacokinetic characteristics of first-line TB drugs in Tanzanian patients using intensive pharmacokinetic sampling. In 20 adult TB patients, plasma concentrations were determined just before and at 1, 2, 3, 4, 6, 8, 10, and 24 h after observed drug intake with food to estimate the areas under the curve from 0 to 24 h (AUC0-24) and peak plasma concentrations (Cmax) of isoniazid, rifampin, pyrazinamide, and ethambutol. Acetylator status for isoniazid was assessed phenotypically using the isoniazid elimination half-life and the acetylisoniazid/isoniazid metabolic ratio at 3 h postdose. The geometric mean AUC0-24s were as follows: isoniazid, 11.0 h · mg/liter; rifampin, 39.9 h · mg/liter; pyrazinamide, 344 h · mg/liter; and ethambutol, 20.2 h · mg/liter. The Cmax was below the reference range for isoniazid in 10/19 patients and for rifampin in 7/20 patients. In none of the patients were the Cmaxs for pyrazinamide and ethambutol below the reference range. Elimination half-life and metabolic ratio of isoniazid gave discordant phenotyping results in only 2/19 patients. A substantial proportion of patients had an isoniazid and/or rifampin Cmax below the reference range. Intake of TB drugs with food may partly explain these low drug levels, but such a drug intake reflects common practice. The finding of low TB drug concentrations is concerning because low concentrations have been associated with worse treatment outcome in several other studies.

Background: To evaluate the effect of rifampicin-based tuberculosis (TB) treatment on the pharmacokinetics of efavirenz/tenofovir/emtricitabine in a fixed-dose combination tablet, and vice versa, in Tanzanian TB-HIV-coinfected patients., Methods: This was a Phase II open-label multiple dose pharmacokinetic and safety study. This study was conducted in TB-HIV-coinfected Tanzanian patients who started TB treatment (rifampicin/isoniazid/pyrazinamide/ethambutol) at week 1 to week 8 and continued with rifampicin and isoniazid for another 16 weeks. Antiretroviral treatment (ART) of efavirenz/tenofovir/emtricitabine in a fixed-dose combination tablet was started at week 4 after initiation of TB treatment. A 24-h pharmacokinetic sampling curve was recorded at week 8 (with TB treatment) and week 28 (ART alone). For TB drugs, blood samples at 2 and 5 h post-dose were taken at week 3 (TB treatment alone) and week 8 (with ART)., Results: A total of 25 patients (56% male) completed the study; 21 had evaluable pharmacokinetic profiles. The area under the concentration-time curve 0-24 h post-dose of efavirenz, tenofovir and emtricitabine were slightly higher when these drugs were coadministered with TB drugs; geometric mean ratios (90% CI) were 1.08 (0.90, 1.30), 1.13 (0.93, 1.38) and 1.05 (0.85, 1.29), respectively. For TB drugs, equivalence was suggested for peak plasma concentrations when administered with and without efavirenz/tenofovir/emtricitabine. Adverse events were mostly mild and no serious adverse events or drug discontinuations were reported., Conclusions: Coadministration of efavirenz, tenofovir and emtricitabine with a standard first-line TB treatment regimen did not significantly alter the pharmacokinetic parameters of these drugs and was tolerated well by Tanzanian TB patients who are coinfected with HIV.