Exposure and health risk assessment of applicators to DDT during indoor residual spraying in malaria vector control program

We assessed exposure of applicators, health risk of DDT to the applicators and evaluated the applicability of existing pesticide exposure models for indoor residual spraying (IRS). Patch sampling for dermal and personal air sampler for inhalation exposure were used in monitoring 57 applicators on the exposure assessment to DDT. The exposure of the applicators was also estimated using three exposure models. The mean actual dermal exposure was 449 mg total DDT per applicator per one house treatment. The applicators were exposed to DDT much beyond the estimated AOEL (acceptable operator exposure level) of DDT. The exposure estimated with ConsExpo 5.0 b01 model is situated between the median and the 75th percentile of the experimental data. On the other hand, spraying model 1 and spraying model 10 overestimate the exposure. Thus, these three models cannot be directly used for the particular circumstances of IRS as a tool for risk assessment. In general, use of DDT in IRS as a control method for malaria mosquitoes holds a high health risk for the applicators. Strict implementation of spraying procedures stated in the IRS manual of World Health Organization (WHO) is necessary to reduce the exposure level and health risk of applicators to DDT

Removal of arsenic (V) from aqueous solutions using chitosan-red scoria and chitosan-pumice blends

In different regions across the globe, elevated arsenic contents in the groundwater constitute a major health problem. In this work, a biopolymer chitosan has been blended with volcanic rocks (red scoria and pumice) for arsenic (V) removal. The effect of three blending ratios of chitosan and volcanic rocks (1:2, 1:5 and 1:10) on arsenic removal has been studied. The optimal blending ratio was 1:5 (chitosan:volcanic rocks) with maximum adsorption capacity of 0.72 mg/g and 0.71 mg/g for chitosan:red scoria (Ch-Rs) and chitosan:pumice (Ch-Pu), respectively. The experimental adsorption data fitted well a Langmuir isotherm (R-2 > 0.99) and followed pseudo-second-order kinetics. The high stability of the materials and their high arsenic (V) removal efficiency (similar to 93%) in a wide pH range (4 to 10) are useful for real field applications. Moreover, the blends could be regenerated using 0.05 M NaOH and used for several cycles without losing their original arsenic removal efficiency. The results of the study demonstrate that chitosan-volcanic rock blends should be further explored as a potential sustainable solution for removal of arsenic (V) from water

Capacity of health facilities for diagnosis and treatment of HIV/AIDS in Ethiopia

Background: There are dearth of literature on the capacity of the health system to diagnose and treat HIV/AIDS in Ethiopia. In this study we evaluated the capacity of health facilities for HIV/AIDS care, its spatial distribution and variations by regions and zones in Ethiopia. Methods: We analyzed the Service Provision Assessment plus (SPA+) survey data that were collected in 2014 in all regions of Ethiopia. We assessed structural, process and overall capacity of the health system based on the Donabedian quality of care model. We included 5 structural and 8 process indicators and overall capacity score was constructed by taking the average of all indicators. Multiple linear regression was done using STATA 14 to assess the association of the location and types of health facilities with overall capacity score. Maps displaying the average capacity score at Zonal level were produced using ArcGIS Desktop v10.3 (Environmental Systems Research Institute Inc., Redlands CA, USA). Results: A total of 873 health facilities were included in the analysis. Less than 5% of the private facilities provided antiretroviral therapy (ART); had national ART guideline, baseline CD4 count or viral load and tuberculosis screening mechanisms. Nearly one-third of the health centers (34.9%) provided ART. Public hospitals have better capacity score (77.1%) than health centers (45.9%) and private health facilities (24.8%). The overall capacity score for urban facilities (57.1%) was higher than that of the rural (38.2%) health facilities (β = 15.4, 95% CI: 11.7, 19.2). Health centers (β = − 21.4, 95% CI: -25.4, − 17.4) and private health facilities (β = − 50.9, 95% CI: -54.8, − 47.1) had lower overall capacity score than hospitals. Facilities in Somali (β = − 13.8, 95% CI: -20.6, − 7.0) and SNNPR (β = − 5.0, 95% CI: -9.8, − 0.1) regions had lower overall capacity score than facilities in the Oromia region. Zones located in emerging regions such as Gambella and Benishangul Gumz and in remote areas of Oromia and SNNPR had lower capacity score in terms of process indicators. Conclusions: There is a significant geographical heterogeneity on the capacity of health facilities for HIV/AIDS care and treatment in Ethiopia. Targeted capacity improvement initiatives are recommended with focus on health centers and private health facilities, and emerging Regions and the rural and remote areas

The effect of household heads training on long-lasting insecticide-treated bed nets utilization: a cluster randomized controlled trial in Ethiopia

<p>Abstract</p> <p>Background</p> <p>Long-lasting insecticide-treated bed nets (LLITN) have demonstrated significant impact in reducing malaria-related childhood morbidity and mortality. However, utilization of LLITN by under-five children is not satisfactory in many sub-Saharan African countries due to behavioural barriers. Previous studies had focused on the coverage and ownership of LLITN. The effect of skill-based training for household heads on LLITN utilization had not yet been investigated. A cluster-randomized trial on the effect of training of household heads on the use of LLITN was done in Ethiopia to fill this knowledge gap.</p> <p>Methods</p> <p>The study included 22 (11 intervention and 11 control) villages in southwest Ethiopia. The intervention consisted of tailored training of household heads about the proper use of LLITN and community network system. All households in each group received free LLITN. Data were collected at baseline, six and 12 months of the follow up periods. Utilization of LLITN in the control and intervention villages was compared at baseline and follow up periods.</p> <p>Results</p> <p>A total of 21,673; 14,735 and 13,758 individuals were included at baseline, sixth and twelfth months of the project period. At the baseline survey, 47.9% of individuals in the intervention villages and 68.4% in the control villages reported that they had utilized LLITN the night before the survey. At the six month, 81.0% of individuals in the intervention villages and 79.3% in the control villages had utilized LLITN. The utilization of LLITN in all age groups in the intervention villages was increased by 17.7 percentage point (95% CI 9.7-25.6) at sixth month and by 31.0 percentage point (95% CI 16.9-45.1) at the twelfth month. Among under-five children, the LLITN utilization increased by 31.6 percentage point (95% CI 17.3-45.8) at the sixth month and 38.4 percentage point (95% CI 12.1-64.7) at the twelfth months of the project period.</p> <p>Conclusion</p> <p>Household level skill-based training has demonstrated a marked positive effect in the utilization of LLITN. The effect of the intervention steadily increased overtime. Therefore, distribution of LLITN should be accompanied by a skill-based training of household heads to improve its utilization.</p> <p>Trail registration</p> <p>Australian New Zealand Clinical Trials Registry (ACTR number: <a href="http://www.anzctr.org.au/ACTRN12610000035022.aspx">ACTRN12610000035022</a>).</p

The effect of household heads training about the use of treated bed nets on the burden of malaria and anaemia in under-five children: a cluster randomized trial in Ethiopia

<p>Abstract</p> <p>Background</p> <p>Long-lasting insecticide-treated bed nets (LLITN) have demonstrated a significant effect in reducing malaria-related morbidity and mortality. However, barriers on the utilization of LLITN have hampered the desired outcomes. The aim of this study was to assess the effect of community empowerment on the burden of malaria and anaemia in under-five children in Ethiopia.</p> <p>Methods</p> <p>A cluster randomized trial was done in 22 (11 intervention and 11 control) villages in south-west Ethiopia. The intervention consisted of tailored training of household heads about the proper use of LLITN and community network system. The burden of malaria and anaemia in under-five children was determined through mass blood investigation at baseline, six and 12 months of the project period. Cases of malaria and anaemia were treated based on the national protocol. The burden of malaria and anaemia between the intervention and control villages was compared using the complex logistic regression model by taking into account the clustering effect. Eight Focus group discussions were conducted to complement the quantitative findings.</p> <p>Results</p> <p>A total of 2,105 household heads received the intervention and the prevalence of malaria and anaemia was assessed among 2410, 2037 and 2612 under-five children at baseline, six and 12 months of the project period respectively. During the high transmission/epidemic season, children in the intervention arm were less likely to have malaria as compared to children in the control arm (OR = 0.42; 95%CI: 0.32, 0.57). Symptomatic malaria also steadily declined in the intervention villages compared to the control villages in the follow up periods. Children in the intervention arm were less likely to be anaemic compared to those in the control arm both at the high (OR = 0.84; 95%CI: 0.71, 0.99)) and low (OR = 0.73; 95%CI: 0.60, 0.89) transmission seasons.</p> <p>Conclusion</p> <p>Training of household heads on the utilization of LLITN significantly reduces the burden of malaria in under-five children. The Ministry of Health of Ethiopia in collaboration with other partners should design similar strategies in high-risk areas to control malaria in Ethiopia.</p> <p>Trial registration</p> <p>Australia and New Zealand Clinical Trials Register (ANZCTR): <a href="http://www.anzctr.org.au/ACTRN12610000035022.aspx">ACTRN12610000035022</a></p

Effect of training on the use of long-lasting insecticide-treated bed nets on the burden of malaria among vulnerable groups, south-west Ethiopia: baseline results of a cluster randomized trial

<p>Abstract</p> <p>Background</p> <p>In Ethiopia, the utilization of long-lasting insecticide-treated bed nets (LLITN) is hampered by behavioural factors such as low awareness and negative attitude of the community. The aim of this study was to present the design and baseline results of a cluster randomized trial on the effect of training of household heads on the use of LLITN.</p> <p>Methods</p> <p>This baseline survey was undertaken from February to March, 2009 as part of a randomized cluster trial. A total of 11 intervention and 11 control <it>Gots </it>(villages) were included in the Gilgel Gibe Field Research Centre, south-west Ethiopia. House to house visit was done in 4135 households to collect information about the use of LLITN and socio-demographic variables. For the diagnosis of malaria and anaemia, blood samples were collected from 2410 under-five children and 242 pregnant women.</p> <p>Results</p> <p>One fourth of the households in the intervention and control <it>Gots </it>had functional LLITN. Only 30% of the observed LLITN in the intervention and 28% in the control <it>Gots </it>were hanged properly. Adults were more likely to utilize LLITN than under-five children in the control and intervention <it>Gots</it>. The prevalence of malaria in under-five children in the intervention and control <it>Gots </it>was 10.5% and 8.3% respectively. The intervention and control <it>Gots </it>had no significant difference concerning the prevalence of malaria in under-five children, [OR = 1.28, (95%CI: 0.97, 1.69)]. Eight (6.1%) pregnant women in the intervention and eight (7.2%) in the control <it>Gots </it>were positive for malaria (P = 0.9). Children in the intervention <it>Gots </it>were less likely to have anaemia than children in the control <it>Gots</it>, [OR = 0.75, (95%CI: 0.62, 0.85)].</p> <p>Conclusion</p> <p>The availability and utilization of LLITN was low in the study area. The prevalence of malaria and anaemia was high. Intervention strategies of malaria should focus on high risk population and vulnerable groups.</p

Incidence, prevalence and mortality rates of malaria in Ethiopia from 1990 to 2015: analysis of the global burden of diseases 2015

Background: In Ethiopia there is no complete registration system to measure disease burden and risk factors accurately. In this study, the 2015 Global Burden of Diseases, Injuries and Risk factors (GBD) data were used to analyse the incidence, prevalence and mortality rates of malaria in Ethiopia over the last 25 years. Methods: GBD 2015 used verbal autopsy (VA) surveys, reports, and published scientific articles to estimate the burden of malaria in Ethiopia. Age and gender-specific causes of death for malaria were estimated using Cause of Death Ensemble Modelling (CODEm). Results: The number of new cases of malaria declined from 2.8 million (95% uncertainty interval (UI): 1.4-4.5million) in 1990 to 621,345 (95% UI: 462,230-797,442) in 2015. Malaria caused an estimated 30,323.9 deaths (95% UI: 11,533.3-61,215.3) in 1990 and 1,561.7 deaths (95% UI: 752.8-2,660.5) in 2015, a 94.8% reduction over the 25 years. Age-standardized mortality rate of malaria has declined by 96.5% between 1990 and 2015 with an annual rate of change (ARC) of 13.4%. Age-standardized malaria incidence rate among all ages and gender declined by 88.7% between 1990 and 2015. The number of disability-adjusted life years lost (DALY) due to malaria decreased from 2.2 million (95% UI: 0.76-4.7 million) in 1990 to 0.18 million (95% UI: 0.12-0.26 million) in 2015, with a total reduction 91.7%. Similarly, age-standardized DALY rate declined by 94.8% during the same period. Conclusions: Ethiopia has achieved a 50% reduction target of malaria of the Millennium Development Goals (MDGs). The country should strengthen its malaria control and treatment strategies to achieve the Sustainable Development Goals (SDG)

Multiple Insecticide Resistance: An Impediment to Insecticide-Based Malaria Vector Control Program

BACKGROUND: Indoor Residual Spraying (IRS), insecticide-treated nets (ITNs) and long-lasting insecticidal nets (LLINs) are key components in malaria prevention and control strategy. However, the development of resistance by mosquitoes to insecticides recommended for IRS and/or ITNs/LLINs would affect insecticide-based malaria vector control. We assessed the susceptibility levels of Anopheles arabiensis to insecticides used in malaria control, characterized basic mechanisms underlying resistance, and evaluated the role of public health use of insecticides in resistance selection. METHODOLOGY/PRINCIPAL FINDINGS: Susceptibility status of An. arabiensis was assessed using WHO bioassay tests to DDT, permethrin, deltamethrin, malathion and propoxur in Ethiopia from August to September 2009. Mosquito specimens were screened for knockdown resistance (kdr) and insensitive acetylcholinesterase (ace-1(R)) mutations using AS-PCR and PCR-RFLP, respectively. DDT residues level in soil from human dwellings and the surrounding environment were determined by Gas Chromatography with Electron Capture Detector. An. arabiensis was resistant to DDT, permethrin, deltamethrin and malathion, but susceptible to propoxur. The West African kdr allele was found in 280 specimens out of 284 with a frequency ranged from 95% to 100%. Ace-1(R) mutation was not detected in all specimens scored for the allele. Moreover, DDT residues were found in soil samples from human dwellings but not in the surrounding environment. CONCLUSION: The observed multiple-resistance coupled with the occurrence of high kdr frequency in populations of An. arabiensis could profoundly affect the malaria vector control programme in Ethiopia. This needs an urgent call for implementing rational resistance management strategies and integrated vector control intervention