Streams and rivers cover a larger proportion of the Earth’s surface but are highly affected by hu... more Streams and rivers cover a larger proportion of the Earth’s surface but are highly affected by human pressures. Conversely, bioassessment methods are in their infancy in developing countries such as Ethiopia. In this study, we compared 2- and 3-min macroinvertebrate kick samples at multiple locations for both riffle habitat (RH) and multihabitat (MH) approaches. The performance of each method was evaluated statistically using benthic macroinvertebrate metrics and diversity indices. Results of the Kruskal–Wallis analysis in this study showed no significant differences among methods tested in minimally impacted streams in Ethiopia and generally performed equally irrespective of the methods employed except for total abundances and Ephemeroptera abundances. Furthermore, multivariate analysis of the relative abundances of macroinvertebrate communities using analysis of similarity (ANOSIM), RELATE, non-metric multidimensional scaling (MDS), and classification strength-sampling method comparability (CS-SMC) indicated a high similarity in the macroinvertebrate communities recorded among all methods employed in this study area. However, the index of multivariate dispersion (IMD) test showed variations in relative abundances of macroinvertebrate communities among the methods. In summary, if the focus is not on rare taxa and the required information is not dependent on additional evidence provided by the use of lower taxonomic levels of identification (genus and species), the results of the present study support the use of the shorter 2-min RH kick sampling method for the bioassessment of wadeable rivers and streams in Ethiopia.
Journal of Water, Sanitation and Hygiene for Development, 2019
Inadequate improved water supply and sanitation, particularly in refugee camps contribute to the ... more Inadequate improved water supply and sanitation, particularly in refugee camps contribute to the spread of infectious diseases. The study objective was to assess determinants of microbiological quality of drinking water in refugee camps and host communities in Gambella Region, Ethiopia. A cross-sectional study was conducted from September to December 2016 based on structured questionnaire-based interviews and testing household water using the portable Potatest+ water quality testing kit. Data were analyzed and P values <0.05 with 95% confidence interval (CI) were considered statistically significant. Results showed there were significant differences in fecal coliform count (P value = 0.009) and free residual chlorine concentration (P value = 0.01) between the source and stored water samples. Surface water source, water shortages in the previous month, and unavailability of free residual chlorine and caregivers without formal education were the main determinants of microbiological...
Adequate hand washing with soap at five recommended times is particularly important in urban slum... more Adequate hand washing with soap at five recommended times is particularly important in urban slums in developing countries, but which of the recommended times are the most important in the prevention of diarrhea among children under five years of age living in these areas remains unclear. To address this gap, a community-based cross-sectional study was undertaken in the slums of Addis Ababa, Ethiopia between September and November 2014. Data were collected using a pre-tested structured questionnaire and an observational checklist. Multivariable logistic regression with 95% confidence interval (CI) was used for data analysis. Only 4.4% of the households had hand washing facilities within or near a latrine with soap and water access. The average prevalence of hand washing with soap at the five recommended times was 19.8%. One quarter (24.8%) of caregivers washed their hands with soap before feeding a child, 23.8% before preparing food, and 17.1% after defecation. The most important re...
The problem of intermittent piped water supplies that exists in low- and middle-income countries ... more The problem of intermittent piped water supplies that exists in low- and middle-income countries is particularly severe in the slums of sub-Saharan Africa. However, little is known about whether there is deterioration of the microbiological quality of the intermittent piped water supply at a household level and whether it is a factor in reducing or increasing the occurrence of acute diarrhea among under-five children in slums of Addis Ababa. This study aimed to determine the association of intermittent piped water supplies and point-of-use (POU) contamination of household stored water by Escherichia coli (E. coli) with acute diarrhea among under-five children in slums of Addis Ababa. A community-based matched case-control study was conducted from November to December, 2014. Cases were defined as under-five children with acute diarrhea during the two weeks before the survey. Controls were matched by age and neighborhood with cases by individual matching. Data were collected using a p...
ABSTRACT In order to study the effect of leachate recirculation on the quality of leachate and as... more ABSTRACT In order to study the effect of leachate recirculation on the quality of leachate and as an in-situ ammonia–nitrogen removal mechanism, two polyvinyl chloride pipes compacted with a similar raw material composition and working with 4 mL/min and 8 mL/min leachate recirculation flow rate were continuously operated for nine consecutive weeks. In this laboratory scale study, wastewater quality indicator parameters including TS, BOD5, and two selected heavy metals Pb and Cu were used. To this end, the raw material characterization data indicates that all the materials compacted in the reactor were suitable for recirculation of leachate. We found 84.32% BOD5, 82.24% TS, 88.97% COD, 79.2% NH4+–N and 94% Cu removal efficiency that was operated at 4 mL/min in R1 and 66.45% BOD5, 75% COD, 62.98% TS, 67.47% NH4+–N and 79.32% Cu achieved removal efficiency at 8 mL/min in R2. The overall study indicates that leachate recirculation can serve as an in-situ treatment of leachate, even for ammonia nitrogen removal and old landfill leachate, if the working conditions are maintained in appropriate manner.
Waste Management & Research: The Journal for a Sustainable Circular Economy, 2014
In many developing countries, the inadequacy of data regarding the quantity and composition of he... more In many developing countries, the inadequacy of data regarding the quantity and composition of healthcare waste is one of the major reasons for improper healthcare waste management. We investigated the generation rate and composition of healthcare wastes in six public and three private hospitals. We conducted healthcare waste composition and characterization measurements for seven consecutive days in the selected hospitals following the protocol described by the World Health Organization (WHO). The results revealed that the total generation rate of healthcare wastes of hospitals ranged from 0.25 to 2.77 kg/bed/day with a median value of 1.67 kg/bed/day for inpatients to 0.21–0.65 in kg/patient/day with a median value of 0.31 kg/patient/day for outpatients. The waste generation rate in private hospitals (median 3.9 kg/bed/day) was significantly greater (Kruskal–Wallis test, P < 0.05) than in government hospitals (median 1.5 kg/bed/day). The median values of percent hazardous waste...
Background Ethiopia plans to increase its electricity power supply by five-fold over the next fiv... more Background Ethiopia plans to increase its electricity power supply by five-fold over the next five years to fulfill the needs of its people and support the economic growth based on large hydropower dams. Building large dams for hydropower generation may increase the transmission of malaria since they transform ecosystems and create new vector breeding habitats. The aim of this study was to assess the effects of Gilgel-Gibe hydroelectric dam in Ethiopia on malaria transmission and changing levels of prevalence in children. Methods A cross-sectional, community-based study was carried out between October and December 2005 in Jimma Zone, south-western Ethiopia, among children under 10 years of age living in three 'at-risk' villages (within 3 km from dam) and three 'control' villages (5 to 8 km from dam). The man-made Gilgel-Gibe dam is operating since 2004. Households with children less than 10 years of age were selected and children from the selected households were sam...
Streams and rivers cover a larger proportion of the Earth’s surface but are highly affected by hu... more Streams and rivers cover a larger proportion of the Earth’s surface but are highly affected by human pressures. Conversely, bioassessment methods are in their infancy in developing countries such as Ethiopia. In this study, we compared 2- and 3-min macroinvertebrate kick samples at multiple locations for both riffle habitat (RH) and multihabitat (MH) approaches. The performance of each method was evaluated statistically using benthic macroinvertebrate metrics and diversity indices. Results of the Kruskal–Wallis analysis in this study showed no significant differences among methods tested in minimally impacted streams in Ethiopia and generally performed equally irrespective of the methods employed except for total abundances and Ephemeroptera abundances. Furthermore, multivariate analysis of the relative abundances of macroinvertebrate communities using analysis of similarity (ANOSIM), RELATE, non-metric multidimensional scaling (MDS), and classification strength-sampling method comparability (CS-SMC) indicated a high similarity in the macroinvertebrate communities recorded among all methods employed in this study area. However, the index of multivariate dispersion (IMD) test showed variations in relative abundances of macroinvertebrate communities among the methods. In summary, if the focus is not on rare taxa and the required information is not dependent on additional evidence provided by the use of lower taxonomic levels of identification (genus and species), the results of the present study support the use of the shorter 2-min RH kick sampling method for the bioassessment of wadeable rivers and streams in Ethiopia.
Journal of Water, Sanitation and Hygiene for Development, 2019
Inadequate improved water supply and sanitation, particularly in refugee camps contribute to the ... more Inadequate improved water supply and sanitation, particularly in refugee camps contribute to the spread of infectious diseases. The study objective was to assess determinants of microbiological quality of drinking water in refugee camps and host communities in Gambella Region, Ethiopia. A cross-sectional study was conducted from September to December 2016 based on structured questionnaire-based interviews and testing household water using the portable Potatest+ water quality testing kit. Data were analyzed and P values <0.05 with 95% confidence interval (CI) were considered statistically significant. Results showed there were significant differences in fecal coliform count (P value = 0.009) and free residual chlorine concentration (P value = 0.01) between the source and stored water samples. Surface water source, water shortages in the previous month, and unavailability of free residual chlorine and caregivers without formal education were the main determinants of microbiological...
Adequate hand washing with soap at five recommended times is particularly important in urban slum... more Adequate hand washing with soap at five recommended times is particularly important in urban slums in developing countries, but which of the recommended times are the most important in the prevention of diarrhea among children under five years of age living in these areas remains unclear. To address this gap, a community-based cross-sectional study was undertaken in the slums of Addis Ababa, Ethiopia between September and November 2014. Data were collected using a pre-tested structured questionnaire and an observational checklist. Multivariable logistic regression with 95% confidence interval (CI) was used for data analysis. Only 4.4% of the households had hand washing facilities within or near a latrine with soap and water access. The average prevalence of hand washing with soap at the five recommended times was 19.8%. One quarter (24.8%) of caregivers washed their hands with soap before feeding a child, 23.8% before preparing food, and 17.1% after defecation. The most important re...
The problem of intermittent piped water supplies that exists in low- and middle-income countries ... more The problem of intermittent piped water supplies that exists in low- and middle-income countries is particularly severe in the slums of sub-Saharan Africa. However, little is known about whether there is deterioration of the microbiological quality of the intermittent piped water supply at a household level and whether it is a factor in reducing or increasing the occurrence of acute diarrhea among under-five children in slums of Addis Ababa. This study aimed to determine the association of intermittent piped water supplies and point-of-use (POU) contamination of household stored water by Escherichia coli (E. coli) with acute diarrhea among under-five children in slums of Addis Ababa. A community-based matched case-control study was conducted from November to December, 2014. Cases were defined as under-five children with acute diarrhea during the two weeks before the survey. Controls were matched by age and neighborhood with cases by individual matching. Data were collected using a p...
ABSTRACT In order to study the effect of leachate recirculation on the quality of leachate and as... more ABSTRACT In order to study the effect of leachate recirculation on the quality of leachate and as an in-situ ammonia–nitrogen removal mechanism, two polyvinyl chloride pipes compacted with a similar raw material composition and working with 4 mL/min and 8 mL/min leachate recirculation flow rate were continuously operated for nine consecutive weeks. In this laboratory scale study, wastewater quality indicator parameters including TS, BOD5, and two selected heavy metals Pb and Cu were used. To this end, the raw material characterization data indicates that all the materials compacted in the reactor were suitable for recirculation of leachate. We found 84.32% BOD5, 82.24% TS, 88.97% COD, 79.2% NH4+–N and 94% Cu removal efficiency that was operated at 4 mL/min in R1 and 66.45% BOD5, 75% COD, 62.98% TS, 67.47% NH4+–N and 79.32% Cu achieved removal efficiency at 8 mL/min in R2. The overall study indicates that leachate recirculation can serve as an in-situ treatment of leachate, even for ammonia nitrogen removal and old landfill leachate, if the working conditions are maintained in appropriate manner.
Waste Management & Research: The Journal for a Sustainable Circular Economy, 2014
In many developing countries, the inadequacy of data regarding the quantity and composition of he... more In many developing countries, the inadequacy of data regarding the quantity and composition of healthcare waste is one of the major reasons for improper healthcare waste management. We investigated the generation rate and composition of healthcare wastes in six public and three private hospitals. We conducted healthcare waste composition and characterization measurements for seven consecutive days in the selected hospitals following the protocol described by the World Health Organization (WHO). The results revealed that the total generation rate of healthcare wastes of hospitals ranged from 0.25 to 2.77 kg/bed/day with a median value of 1.67 kg/bed/day for inpatients to 0.21–0.65 in kg/patient/day with a median value of 0.31 kg/patient/day for outpatients. The waste generation rate in private hospitals (median 3.9 kg/bed/day) was significantly greater (Kruskal–Wallis test, P < 0.05) than in government hospitals (median 1.5 kg/bed/day). The median values of percent hazardous waste...
Background Ethiopia plans to increase its electricity power supply by five-fold over the next fiv... more Background Ethiopia plans to increase its electricity power supply by five-fold over the next five years to fulfill the needs of its people and support the economic growth based on large hydropower dams. Building large dams for hydropower generation may increase the transmission of malaria since they transform ecosystems and create new vector breeding habitats. The aim of this study was to assess the effects of Gilgel-Gibe hydroelectric dam in Ethiopia on malaria transmission and changing levels of prevalence in children. Methods A cross-sectional, community-based study was carried out between October and December 2005 in Jimma Zone, south-western Ethiopia, among children under 10 years of age living in three 'at-risk' villages (within 3 km from dam) and three 'control' villages (5 to 8 km from dam). The man-made Gilgel-Gibe dam is operating since 2004. Households with children less than 10 years of age were selected and children from the selected households were sam...
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