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Sauli, E.

Publications and source records attributed to Sauli, E..

2 recordsLinked to original sources

Changing Patterns and Drivers of Increased Pesticides Use in Smallholder Vegetable Production Systems in Tanzania

Pesticides use has become a key component of smallholder horticulture production. Therefore, dynamics in pesticides handling need to be ascertained. This study assessed drivers of pesticides use and determinants of changing patterns of pesticides handling practices in smallholder vegetable systems. Data were collected from 385 farmers from Iringa, Arusha, Manyara, and Kilimanjaro regions in Tanzania through an in-depth survey and field observations. A binary probit model was used to derive factors fostering increased pesticides use. Results showed that 47.9 % of all pesticides were wrongly used. Most farmers (88.6%) lacked knowledge of pest control and 88.9% were unaware of safety practices. Disposal methods of empty pesticides foster occupational and environmental exposure (58%). There was an increasing trend in pesticides use (58.4%), accompanied by changing pesticides formulations. Over 60 pesticides with 29 different formulations were used. Mixing pesticides (71.2%), high dose rates with increased frequency of application were observed. Pesticides under Class II WHO hazard (68.9%) dominated. Extremely hazardous (Class Ia) and highly hazardous (Class Ib) were also used. Binary probit model showed that number of crops grown, pesticides mixing, and region contributed positively to the likelihood of increased pesticides use while farmers perception of effectiveness of pesticides, lack of access to safe use information, poor use of safety gears and inability to read pesticides labels had a negative impact. The fate of pesticides use in smallholder vegetable production systems is therefore the culmination of serious health and environmental implications. Excessive pesticides use escalated by increased number of crops, improper use of PPE, and pesticides mixing practices subjects the general population to pesticides environmental exposure thereby jeopardizing sustainability of smallholder vegetable production in Tanzania. Regular training to farmers and extension officers on current and emerging issues on pests and pesticide safe use is vital.

pharmacology and toxicology

Deploying a novel tuberculosis molecular bacterial load assay to assess the elimination rate of Mycobacterium tuberculosis in patients with multidrug-resistant tuberculosis in Tanzania

BackgroundRifampin or multidrug-resistant-tuberculosis (RR/MDR-TB) treatment has transitioned to injectable-free regimens. We tested whether M. tuberculosis (Mtb) elimination rates measured by molecular bacterial load assay (TB-MBLA) in sputa correlate with composition of the RR/MDR-TB antibiotic regimen. MethodsSerial sputa were collected from patients with RR/MDR- and drug-sensitive TB at day 0, 3, 7, 14, and then monthly for 4 months of anti-TB treatment. TB-MBLA was used to quantify viable Mtb 16S rRNA in sputum for estimation of colony-forming-unit per mL (eCFU/mL). Mtb elimination rates were compared among regimens using nonlinear-mixed-effects modeling of repeated measures. ResultsAmong 37 patients with a total of 296 serial sputa; 7 patients received rifampin/isoniazid/pyrazinamide/ethambutol (RHZE), 8 an all-oral bedaquiline-based regimen, 9 an injectable and bedaquiline-containing regimen, and 13 an injectable-containing but bedaquiline-free regimen. The overall mean daily Mtb elimination was -0.24 [95% Confidence-Interval (CI); -0.39 to -0.08)] log10 eCFU/mL, and it varied with treatment-regimen (p < 0.001). Compared to the adjusted Mtb elimination of -0.17 (95% CI; -0.23 to -0.12) for the injectable-containing but bedaquiline-free reference regimen, the elimination rates were -0.62 (95% CI; -1.05 to -0.20) log10 eCFU/mL for the injectable and bedaquiline-containing regimen (p = 0.019), -0.35 (95% CI; -0.65 to -0.13) log10 eCFU/mL for the all-oral bedaquiline-based regimen (p = 0.054), and -0.29 (95% CI; -0.78 to +0.22) log10 eCFU/mL for RHZE (p = 0.332) ConclusionTB-MBLA distinguished Mtb elimination rates in sputa from patients receiving different treatment regimens, suggesting a reliable monitoring tool for RR/MDR-TB, that does not require mycobacterial culture.

microbiology