Effect of agriculture on surface water quantity and quality in Gilgel Gibe watershed, southwestern Ethiopia.

Monitoring water quality and quantity is crucial to be sure that water resources are sustainably used. However, there is no monitoring system of water quantity and quality in southwestern Ethiopia, despite expansion of agricultural activities demanding water resources. The objective of this study was to investigate the effect of agriculture on water quantity and quality with special emphasis on irrigation in southwestern Ethiopia. Data of water quantity was collected from four rivers and four irrigation canals during dry season of 2023. Physico-chemical water quality data was collected from 35 sites. Water quantity was calculated by estimating the water discharge of the rivers and irrigation canals. Weighted arithmetic water quality index was calculated to assess the status of the studied rivers. Principal component analysis was used to identify the relation of the sites with water quality parameters. This study revealed that the average amount of abstracted water for irrigation from the four studied rivers was 22,399 m3/day during the studied period, and the average percentage of abstracted water was 17%. Sites downstream of the irrigation site were characterized by poor water quality compared with the upstream sites. Sites surrounded by agricultural land use were correlated with chemical oxygen demand, electric conductivity, nitrate, orthophosphate, water temperature, and pH, whereas all sites surrounded by forest were positively correlated with dissolved oxygen. This study indicates that agricultural activities have a negative impact on surface water quality and quantity if not managed properly. Hence, we recommend sustainable use of water resources for the planned irrigation expansion.

Seasonal Variations in Household Water Use, Microbiological Water Quality, and Challenges to the Provision of Adequate Drinking Water: A Case of Peri-urban and Informal Settlements of Hosanna Town, Southern Ethiopia.

Several studies have been conducted on household water use and microbial water quality globally. However, studies that considered seasonal variability of household water use and microbial water quality were limited. Therefore, this study investigated the seasonal variability of household water use, microbiological water quality, and challenges to the provision of adequate water in the peri-urban and informal settlements of Hosanna town, Southern Ethiopia. A longitudinal study was conducted on 288 households. The data was gathered using a pretested structured questionnaire, laboratory-analysis, interviews, storage-container inventories, focus group discussions, key-informant interviews, and an observational checklist. The data was analyzed using stepwise-multiple linear regression, bivariate and multivariable logistic regression, thematic-analysis, t-tests, and non-parametric-tests. Households were visited for 7 consecutive days during the dry and rainy seasons to account for changes in daily and seasonal variation of water use. 440 stored water and 12 source samples were analyzed for E. coli presence during dry and rainy seasons. The prevalence of stored water contamination with E. coli was 43.2% and 34.5% during the dry and rainy seasons, respectively. The per capita water consumption was 19.4 and 20.3 l during the dry and rainy seasons, respectively. Piped water on-premises, small family size, volume, and number of water storage containers were significant predictors of per capita water consumption in both seasons. Piped water off-premises, storing water for more than 3 days, uncovered, and wide-mouthed water storage containers were significantly associated with the presence of E. coli in water in both seasons. Seasonal variability of household water use and microbiological water quality was statistically significant, which is a significant public health concern and needs intervention to enhance water quantity and quality to mitigate the risk of waterborne diseases. Findings also suggest seasonal monitoring of the safety of drinking water to ensure that the water is safe and healthy.

Effect of a chimney-fitted improved stove on pregnancy outcomes in Northwest Ethiopia: a randomized controlled trial.

BACKGROUND: Exposure to household air pollution during pregnancy has been linked to adverse pregnancy outcomes. Improved stove was implemented in Ethiopia to reduce this exposure and related health problems. However, the effects of improved stove interventions on pregnancy outcomes remains uncertain. METHOD: Individually randomized stove replacement trial was conducted among 422 households in six low-income rural kebeles of Northwestern Ethiopia. Pregnant women without known health conditions were recruited at ≤ 24 weeks gestation and randomized to an intervention or control group with a 1:1 ratio. A baseline survey was collected and a balance test was done. Two-sided independent samples t-test for continuous outcomes and chi-square for categorical variables were used to compare the effect of the intervention between the groups. Mean differences with 95% CIs were calculated and a p-value of < 0.05 was considered statistically significant. RESULT: In this study, the mean birth weight was 3065 g (SD = 453) among the intervention group and not statistically different from 2995 g (SD = 541) of control group. After adjusting for covariates, infants born from intervention group weighed 55 g more [95% CI: - 43 to 170) than infants born from the control group, but the difference was not statistically significant (P = 0.274). The respective percentages for low birth weight were 8% and 10.3% for intervention and control groups respectively (P = 0.346). However, the average gestational age at delivery was higher among improved stove users (38 weeks (SD = 8.2) compared to control groups 36.5 weeks (SD = 9.6) with statistically significant difference at 0.91 weeks (95% CI: 0.52 to 1.30 weeks, p < 0.001). The corresponding difference in risk ratio for preterm birth is 0.94 (95% CI:0.92 to 0.97; p < 0.001). The percentages for maternal complications, stillbirth, and miscarriage in the intervention group were not statistically different from the control group. CONCLUSIONS: While the increase in average birth weight among babies born to mothers using improved stoves was not statistically significant, babies had a longer gestational age on average, offering valuable health benefits. However, the study didn't find a significant impact on other pregnancy outcomes like stillbirth, miscarriage, or maternal complications. TRIAL REGISTRATION: The study was registered at the Pan African Clinical Trial Registry website under the code PACTR202111534227089, ( https://pactr.samrc.ac.za/ (Identifier). The first trial registration date was (11/11/2021).

The effect of chimney fitted improved stove on kitchen fine particulate matter (PM2.5) concentrations in rural Ethiopia: Evidence from a randomized controlled trial.

BACKGROUND: Millions of Ethiopian people cook with biomass fuels using traditional stoves, releasing harmful pollutants and contributing to a significant public health crisis. Improved stoves offer a potential escape route, but their effectiveness needs close scrutiny. This study delves into the impact of chimney-fitted stoves on kitchen PM2.5 concentrations in rural Ethiopian households. METHOD: We conducted a randomized controlled trial with 86 households equally divided (1:1 ratio) between intervention and control groups. The 24-h average kitchen PM2.5 concentrations was measured using Particle and Temperature Sensor (PATS+) at baseline and after intervention. All relevant sociodemographic and cooking related characteristics were collected at baseline and dynamic characteristics were updated during air monitoring visits. Three distinct statistical models, including independent sample t-tests, paired sample t-tests and one-way analysis of variance were used to analyze the data using Statistical Package for the Social Sciences (SPSS) software for Windows (v 24.0). RESULT: At baseline, the average 24-h kitchen PM2.5 concentrations were 482 µg/m3 (95% CI: 408, 557) for the control and 405 µg/m3 (95% CI: 318, 492) for the intervention groups. Despite remaining elevated at 449 µg/m3 (95% CI: 401, 496) in the control group, PM2.5 concentrations reduced to 104 µg/m3 (95% CI: 90,118) in the intervention group, indicating a statistically significant difference (t = 6.97, p < 0.001). All three statistical analyses delivered remarkably consistent results, estimating a PM2.5 reductions of 74% with the before-and-after approach, 76% when comparing groups, and 74% for difference in difference analysis. Beyond the overall reduction, homes with primary school completed women, larger kitchens, smaller family size, and those specifically baking Injera (the traditional energy-intensive staple food), witnessed even greater drops in PM2.5 levels. CONCLUSION: Pregnant women in our study encountered dangerously high PM2.5 exposures in their kitchens. While the intervention achieved a significant PM2.5 reductions, unfortunately remained above the WHO's safe limit, highlighting the need for further interventions.

Analysis of Achyranthes aspera leaf extract and acute toxicity study on fingerlings of Nile tilapia, Oreochromis niloticus.

Schistosomiasis is a debilitating chronic disease with great socioeconomic and public health impact affecting the poor rural populations who lack access to sanitation, and safe water supply. The high cost of synthetic molluscicides, their toxicity to non-target organisms, and their persistence in the environment have forced the research of plant-derived molluscicides. Although plant molluscicides are cheap, biodegradable, ecofriendly and less toxic to higher animals, unregulated applications could affect non-target organisms. Therefore, ecotoxicological studies are essential to assess the toxicity of these substances to economically and ecologically significant fish species and to establish safe dosage level. This study is intended to investigate the acute toxicity of a molluscicidal plant Achyranthes aspera to Nile tilapia fingerlings, Oreochromis niloticus (O. niloticus) (n = 7) were exposed to serial dilutions of A. aspera leaf aqueous extract using maceration method for 96 h in triplicate setup. Phytoconstituents were identified by GC-MS. Mortality data were analyzed by probit regression to determine lethal concentrations. The NOAEC was ascertained through hypothesis testing based on survival data. The respective piscicidal LC1 and LC10 values were 897.43 and 1063.87 mg/L while the LC50 is 1310.74 mg/L. In addition, the NOAEC was 1100 mg/L (p > 0.05). This piscicidal toxicity is much lower than its molluscicidal potency may be due to the presence of rotenones and triterpenoides which are commonly found in piscicidal natural products. The GC-MS analysis revealed 12 phytoconstituents including a monoterpene. This study indicates that A. aspera has low toxicity to Nile tilapia could be due to monoterpenes are nontoxic. The findings of this study demonstrate that, at this dose, the plant is safe to the test fish. Thus it can be effective, eco-friendly and sustainable alternative for the development of molluscicides for snail control.

Kitchen fine particulate matter (PM2.5) concentrations from biomass fuel use in rural households of Northwest Ethiopia.

Background: Combustion of solid biomass fuels using traditional stoves which is the daily routine for 3 billion people emits various air pollutants including fine particulate matter which is one of the widely recognized risk factors for various cardiorespiratory and other health problems. But, there is only limited evidences of kitchen PM2.5 concentrations in rural Ethiopia. Objective: This study is aimed to estimate the 24-h average kitchen area concentrations of PM2.5 and to identify associated factors in rural households of northwest Ethiopia. Method: The average kitchen area PM2.5 concentrations were measured using a low-cost light-scattering Particle and Temperature Sensor Plus (PATS+) for a 24-h sampling period. Data from the PATS+ was downloaded in electronic form for further analysis. Other characteristics were collected using face-to-face interviews. Independent sample t-test and one-way analysis of variance were used to test differences in PM2.5 concentrations between and among various characteristics, respectively. Result: Mixed fuels were the most common cooking biomass fuel. The 24-h average kitchen PM2.5 concentrations was estimated to be 405 µg/m3, ranging from 52 to 965 µg/m3. The average concentrations were 639 vs. 336 µg/m3 (p < 0.001) in the thatched and corrugated iron sheet roof kitchens, respectively. The average concentration was also higher among mixed fuel users at 493 vs. 347 µg/m3 (p = 0.042) compared with firewood users and 493 vs. 233 µg/m3 (p = 0.007) as compared with crop residue fuel users. Statistically significant differences were also observed across starter fuel types 613 vs. 343 µg/m3 (p = 0.016) for kerosene vs. dried leaves and Injera baking events 523 vs. 343 µg/m3 (p < 0.001) for baked vs. not baked events. Conclusion: The average kitchen PM2.5 concentrations in the study area exceeded the world health organization indoor air quality guideline value of 15 µg/m3 which can put pregnant women at greater risk and contribute to poor pregnancy outcomes. Thatched roof kitchen, mixed cooking fuel, kerosene fire starter, and Injera baking events were positively associated with high-level average kitchen PM2.5. concentration. Simple cost-effective interventions like the use of chimney-fitted improved stoves and sensitizing women about factors that aggravate kitchen PM2.5 concentrations could reduce kitchen PM 2.5 levels in the future.

Access to Drinking Water, Sanitation, and Hand Hygiene Facilities in the Peri-Urban and Informal Settlements of Hosanna Town, Southern Ethiopia.

Access to water, sanitation, and hygiene (WASH) facilities and practices have been extensively studied in urban and rural areas. However, there is a paucity of information on the coverage of water, sanitation, and hygiene facilities in the peri-urban and informal settlement areas, which could potentially exacerbate the spread of water, sanitation, and hygiene-related diseases. Therefore, this study was designed to examine access to drinking water, sanitation, and hand hygiene facilities and their determinant factors in the peri-urban and informal settlements of Hosanna town. A community-based cross-sectional study involving 292 households was conducted in 3 kebeles of Hosanna town. The primary data was collected using a pretested structured questionnaire and an observational checklist. Bivariate and multivariable logistic regressions were used to analyze the data. All the households (100%) had access to piped water on and off-premises, but the reliability of the water sources was a big challenge. Findings revealed that only 35.1% and 16.8% of the households had basic sanitation and basic handwashing facilities, respectively. Households with a middle income were identified as a determinant factor for the presence of piped water on premises (AOR = 2.23; 95% CI = 1.24-4.00), improved sanitation (AOR = 2.17; 95% CI = 1.17-4.03) and handwashing facilities (AOR = 4.36; 95% CI = 1.98-9.62). Piped water on premises was also another strong predictor of the availability of improved sanitation (AOR = 3.34; 95% CI = 1.99-5.62) and handwashing facilities (AOR = 8.18; 95% CI = 4.08-16.42). The majority of the studied households living in the selected peri-urban and informal settlements had access to unreliable drinking water sources. The study also revealed that households had poor access to basic sanitation and basic handwashing facilities. Hence, the findings call for solid government interventions to improve the reliability of the drinking water sources, basic sanitation coverage, and availability of basic handwashing facilities.

Depth profile of reservoir water quality in the Southwest of Ethiopia.

The objective of this research was to investigate the variation of water quality parameters at different depths of the Gilgel Gibe I reservoir in Oromia Jimma zone during wet seasons. Five stations within the reservoir were selected, and water quality parameters were determined at four different depths (surface, 5 m, 10 m, and 15 m). Water quality parameters were analyzed on-site using a HACH, HQ40d portable multi-meter, and turbidity was measured using Wag tech turbidity meter and in the laboratory using the standard method. Comparison of water quality parameters among depths were conducted using one-way ANOVA and Tukey's pairwise comparisons with 5% significance level. The probable contributing source of the investigated physicochemical water quality parameters at different depth was identified using Principal components analysis. The results show that depth wise except for total suspended solids (TSS), total dissolved solids (TDS), total phosphorus (TP) and soluble reactive phosphorus (SRP) the rest showed statistically significant difference at p < 0.05 level. Negative correlations were found between depth and dissolved oxygen (DO), water temperature, pH, nitrate (N03-) and chlorophyll a (Chl.a) while positive correlations were found between electrical conductivity (EC), biochemical oxygen demand (BOD5), turbidity and N03-. The study revealed that the release of nutrients associated with increased concentration of BOD5 at the bottom depth caused low concentration of dissolved oxygen due to oxygen consumption. This was further aggravated through the decomposition of organic matter, indicating organic pollution resulting from runoff from the catchment. The presence of dense masses of blue-green algae in the pelagic zone of Gilgel Gibe I reservoir suggested the presence of ample nutrients for its blooming and significant reduction of water quality, indicating possible eutrophic conditions. Therefore, catchment management is required to protect aquatic life and the reservoir function as a whole from reservoir water quality degradation.

Environmental exposures and adverse pregnancy outcomes in Ethiopia: A systematic review and meta-analysis.

BACKGROUND: Maternal exposures to environmental hazards during pregnancy are key determinants of birth outcomes that affect health, cognitive and economic status later in life. In Ethiopia, various epidemiological evidences have suggested associations between environmental exposures such as household air pollution, cigarette smoking, and pesticide exposure and pregnancy outcomes such as low birth weight, preterm birth, and birth defects. OBJECTIVE: This review aimed at generating summarized evidence on the association between maternal exposure to environmental factors (household air pollution, cigarette smoking, and pesticide) and pregnancy outcomes (birth weight, preterm birth, and birth defects) in Ethiopia. METHOD: A systematic literature search was performed using PubMed, Google Scholar, and the Cochrane Library databases. All observational study designs were eligible for inclusion in the review. Quality assessment was conducted using the Newcastle-Ottawa Scale (NOS) quality assessment tools adopted for case-control and cross-sectional studies. The random-effects model was applied in computing the pooled estimates and their corresponding 95% confidence interval (CI). Funnel and Doi plots were used for detecting the potential publication bias. All statistical analyses were performed using comprehensive meta-analysis (CMA 2.0) and MetaXL version 5.3 software. RESULT: The pooled estimates revealed that prenatal biomass fuel use increased the risk of giving a low birth weight baby by twofold (OR = 2.10, 95% CI: 1.33-3.31), and has no separate kitchen increases the risk of having low birth weight baby nearly by two and half times (OR = 2.48, 95% CI: 1.25-4.92). Overall, using biomass fuel as the main energy source for cooking and /or having no separate kitchen from the main house is 2.37 times more likely to give low birth weight babies (OR = 2.37, 95% CI: 1.58-3.53). Active cigarette smoker women were 4 times (OR = 4.11, 95% CI: 2.82-5.89) more prone to have low birth weight babies than nonsmokers; and passive smoker women were 2.6 times (OR = 2.63, 95% CI: 1.09-6.35) more risked to give low birth weight babies. It was also estimated that active cigarette smoker women were nearly 4 times (OR = 3.90, 95% CI: 2.36-6.45) more likely to give preterm birth babies. Pesticide exposure during pregnancy also increases the risk of the birth defect 4 times (OR = 4.44, 95% CI: 2.61-7.57) compared with non-exposed pregnant women. CONCLUSION: Household air pollution from biomass fuel use, active and passive cigarette smoking, and pesticide exposures are significantly associated environmental risk factors for low birth weight, preterm birth, and birth defects in Ethiopia. Therefore, Pregnant and lactating women should be aware of these environmental hazards during pregnancy. Promoting clean energy and improved and efficient stoves at the household level will help to reduce household air pollution-related adverse health effects. TRIAL REGISTRATION: PROSPERO 2022: CRD42022337140.

Bacterial hazard identification and exposure assessment of raw milk consumption in Jimma zone, South West Ethiopia.

BACKGROUND: Raw milk may contain pathogenic microorganism that can sometimes fatally affect the health of consumers. However, risks related to raw milk consumption in Southwest Ethiopia are not well studied. The aim of this study was to evaluate the presence of five target pathogenic bacteria including Escherichia coli O157:H7, Salmonella enterica Typhimurium, Staphylococcus aureus, Listeria monocytogenes, and Campylobacter jejuni in raw milk and to assess exposure associated with the consumption of raw milk. METHOD: A cross-sectional study was carried out between November 2019 and June 2020 to in Jimma zone, Southwest Ethiopia. Laboratory analysis was conducted on milk samples collected from Seven Woreda towns, including, Agaro, Yebu, Sekoru, Serbo, Shebe, Seka, Sheki and Jimma town administration. Semi-structured interview questions were administered to collect data on the amount and frequency of consumption. Descriptive statistics were used to summarize laboratory results and questionnaire survey data. RESULT: Among 150 total raw milk samples, about 61.3% were found contaminated by one or more types of pathogens along the dairy value chain. The highest and the least bacterial counts recorded were 4.88 log10cfu/ml and 3.45 log10cfu/ml from E. coli and L. monocytogenes respectively. The mean concentrations of pathogens demonstrated significant statistical difference (p < 0.05) using 95% confidence interval where the prevalence percentage of isolates increased as the milk was transported from farms to the retail outlets. Except for C. jejuni; all other pathogens were detected in the range of unsatisfactory level of milk microbiological quality along the chain. The estimated mean annual risk of acquiring intoxication of E. coli across retailer outlets is 100% whereas salmonellosis, S. aureus intoxication, and listeriosis are 84%, 65% and 63% respectively. CONCLUSION: The study highlights the significant health risks associated with the consumption of raw milk due to its unacceptable microbiological quality. The traditional production and consumption patterns of raw milk are the primary reasons for the high annual probability of infection. Therefore, regular monitoring and implementation of hazard identification and critical control point principles are necessary from raw milk production to retail points to ensure the safety of consumers.

Prevalence of Human and Animal Fasciolosis in Butajira and Gilgel Gibe Health Demographic Surveillance System Sites in Ethiopia.

Fasciolosis is regarded as a major challenge to livestock productivity worldwide, but the burden of disease in humans has only started to receive some attention in the past three decades. The aim of this study was to determine the prevalence of human and animal fasciolosis and its determinant factors in the Gilgel Gibe and Butajira Health and Demographic Surveillance System (HDSS) sites in Ethiopia. A study was undertaken among 389 households across the two sites. Face-to-face interviews were conducted to investigate the knowledge, attitudes and practices of households with regard to fasciolosis. Stools from 377 children aged 7-15 years, and 775 animals (cattle, goats and sheep) were analyzed using a proprietary Fasciola hepatica (F. hepatica) coproantigen ELISA kit. The prevalence of fasciolosis in children was 0.5% and 1% in Butajira and Gilgel Gibe HDSS sites, respectively. The overall prevalence of animal fasciolosis was 29%, 29.2%, and 6% among cattle, sheep, and goats, respectively. More than half of the respondents from Gilgel Gibe (59%, n = 115) did not know that humans can be infected with F. hepatica. The majority of respondents in Gilgel Gibe (n = 124, 64%) and Butajira (n = 95, 50%) did not know the transmission route for fasciolosis. Grazing animals were 7 times more likely to be infected with fasciolosis than animals in cut-and-carry production systems (adjusted odds ratio [AOR] = 7.2; 95% confidence interval [CI]: 3.91-13.17). The findings indicated a lack of knowledge amongst local populations about fasciolosis. Thus, there is a need for public health awareness campaigns about fasciolosis in the study areas.

Effects of Land-Use and Environmental Factors on Snail Distribution and Trematode Infection in Ethiopia.

Freshwater snails are intermediate hosts for several snail-borne diseases affecting humans and animals. Understanding the distribution of snail intermediate hosts and their infection status is very important to plan and implement effective disease prevention and control interventions. In this study, we determined the abundance, distribution, and trematode infection status of freshwater snails in two agro-ecological zones of Ethiopia. We sampled snails from 13 observation sites and examined them for trematode infections using a natural cercarial shedding method. A redundancy analysis (RDA) was used to examine the relationship between snail abundance and environmental variables. Overall, a total of 615 snails belonging to three species were identified. Lymnea natalensis and Bulinus globosus were the dominant snail species, representing 41% and 40% of the total collection, respectively. About one-third of the total snail population (33%) shed cercariae. The cercariae species recorded were Xiphidiocercaria, Brevifurcate apharyngeate distome (BAD), Echinostome, and Fasciola. Snail species were found in high abundance in aquatic habitats located in the agricultural landscape. Therefore, land-use planning and protection of aquatic habitats from uncontrolled human activities and pollution can be considered as important strategies to prevent and control the spread of snail-borne diseases in the region.

Integrated Methods for Household Greywater Treatment: Modified Biofiltration and Phytoremediation.

Most countries around the world have experienced water scarcity in recent decades as fresh water consumption has increased. However, untreated wastewater is routinely discharged into the environment, particularly in developing countries, where it causes widespread environmental and public health problems. The majority of wastewater treatment method publications are heavily focused on high-income country applications and, in most cases, cannot be transferred to low and middle-income countries. An experimental study was conducted to evaluate the performance efficiency of pilot-scale physicochemical and biological treatment methods for the treatment of household greywater in Jimma, Ethiopia. During the experiment, grab samples of greywater were taken from the combined treatment system's influent and effluent every 7 days for 5 weeks and analyzed within 24-48 hours. Temperature, DO, EC, turbidity, TDS, and pH were measured on-site, while BOD, COD, TSS, TP, TN PO4 -3-P, NO3-N, NH4-N, Cl-, and FC were determined in the laboratory. During the five-week pilot-scale combined treatment system monitoring period, the combined experimental and control system's mean percentage reduction efficiencies were as follows: turbidity (97.2%, 92%), TSS (99.2%, 97.2%), BOD5 (94%, 57.4%), COD (91.6%, 54.7%), chloride (61%, 35%), TN (68.24, 42.7%), TP (71.6%, 38.7%), and FC (90%, 71.1%), respectively. Similarly, the combined experimental and control systems reduced PO4 -3-P (12.5 ± 3 mg/L), NO3-N (4.5 ± 3 mg/L), and NH4-N (10.19 ± 2.6 mg/L) to PO4 -3-P (3.5 ± 2.6 mg/L, 7.5 ± 1.6 mg/L), NO3-N (0.8 ± 0.5, 3.6 ± 2.3 mg/L), and NH4-N (7 ± 2.9 mg/L, 15.9 ± 3.9 mg/L), respectively. From the biofiltration and horizontal subsurface flow constructed wetland combined systems, the experimental combined technology emerged as the best performing greywater treatment system, exhibiting remarkably higher pollutant removal efficiencies. In conclusion, the combined biofiltration and horizontal subsurface flow constructed wetland treatment system can be the technology of choice in low-income countries, particularly those with tropical climates.

Habitat preference of blackflies in Omo Gibe river basin (southwest Ethiopia): Implications for onchocerciasis elimination and control.

Ecological control of blackflies (Simulium damnosum) can be an alternative or additional tool to enhance onchocerciasis elimination efforts. However, limited research is conducted on the ecology of blackflies in Ethiopia. In this study, we determined the habitat preference of blackfly larvae and their relationship with aquatic macroinvertebrate predators in the Omo Gibe river basin of southwest Ethiopia. Environmental and biological data were collected from 150 sampling sites during both dry and wet seasons in 2019. Generalized Linear Models (GLMs) were used to identify factors affecting the occurrence and abundance of S. damnosum larvae. Canonical Correspondence Analysis (CCA) was used to investigate the relationship between environmental and biological variables and the abundance of S. damnosum larvae. The findings of this study indicated the abundance of S. damnosum larvae increased with increasing turbidity, alkalinity and altitude, but decreased with increasing concentrations of five-day Biological Oxygen Demand (BOD5), orthophosphate and magnesium ion. Both the presence and abundance of S. damnosum larvae decreased with the increasing abundance of stonefly larvae (Perlidae). Simulium damnosum larvae were found less likely in the presence of mayfly larvae (Baetidae) and were less abundant where Chironomidae are abundant. In conclusion, the findings of this study showed that the habitat preference of S. damnosum larvae is determined by environmental factors and that the presence and abundance of the larvae are affected by macroinvertebrate predators. It is essential to establish buffer zones as a part of watershed management to retain pollutants and prevent them from entering directly into water courses to improve water quality and the assemblages of macroinvertebrate predators and enhance biocontrol of blackflies.

Refining benthic macroinvertebrate kick sampling protocol for wadeable rivers and streams in Ethiopia.

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.

Occurrence, Risk Factors, and Antimicrobial Susceptibility Test of Thermophilic Campylobacter Species of Bovine Carcass at Municipal Abattoir and Butcher Shops of Jimma Town, Southwest Ethiopia.

BACKGROUND: Although Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) cause acute diarrheal diseases in people all over the world, they are most commonly seen in other mammalian species and are a seemingly healthy carrier condition. Humans in Ethiopia, on the other hand, are largely unaware of the existence of Campylobacter in food animals as potential sources of infection. OBJECTIVE: To determine the occurrence, risk factors, and antimicrobial susceptibility pattern of thermophilic Campylobacter species in bovine raw meat from the abattoir and butcher shops. METHODS: Swab samples were collected from 177 cattle carcasses (from abattoir 93 and butcher shops 84) and cultured using standard methods. An antimicrobial susceptibility test was performed using the disk diffusion method towards eleven antimicrobial agents. RESULTS: The overall prevalence of thermophilic Campylobacter species was 14 (7.9%). From these, 11 (78.6%) were identified to be C. jejuni and 3 (21.4%) were C. coli. Lack of handwashing before meat processing and after visiting the toilet, meat contact with floors, walls, or soiling during preparation, and lack of training were the most important factors independently associated with (p<0.05) the prevalence of Campylobacter species contamination. The highest level of antimicrobial resistance of the Campylobacter isolates was recorded to ampicillin (10µg) (100%), followed by amoxicillin (30µg) (78.6%) and sulphamethoxazole-trimethoprim (57.1%) while the least resisted antimicrobials were streptomycin (25µg), erythromycin (15µg), oxytetracycline (30µg) (each 28.6%), kanamycin (30µg) 14.3%, chloramphenicol (30µg) and gentamycin (10µg) (each 7.1%). CONCLUSION: Despite the low prevalence of thermophilic Campylobacter in the current investigation, it may pose a significant public health threat. As a result, it is vital to give retailers and customers extensive education, training, and knowledge about the correct handling and cooking of animal-derived goods. Furthermore, antimicrobials should be used with caution in both veterinary and human treatment regimens as well as a wider examination of antimicrobial resistance patterns for the use of well-targeted antimicrobials.

Mesocosm Experiments to Quantify Predation of Mosquito Larvae by Aquatic Predators to Determine Potential of Ecological Control of Malaria Vectors in Ethiopia.

Malaria parasites are transmitted to humans by infectious female Anopheles mosquitoes. Chemical-insecticide-based mosquito control has been successful in reducing the burden of malaria. However, the emergence of insecticide resistance in malaria vectors and concerns about the effect of the chemicals on the environment, human health, and non-target organisms present a need for new or alternative vector control intervention tools. Biocontrol methods using aquatic invertebrate predators have emerged as a potential alternative and additional tool to control mosquito populations. Ecological control specifically makes use of species insights for improving the physical habitat conditions of competitors and predators of vectors. A first step towards this is to gain knowledge on the predation potential of several typically present macroinvertebrates. Hence, this study aimed at (1) examining the influence of the predation of hemipterans on the number of emerging adult mosquitoes and (2) detecting Anopheles mosquito DNA in the gut of those predators. The prey and predators were collected from a range of water bodies located in the Gilgel Gibe watershed, southwest Ethiopia. A semi-field study was carried out using mesocosms which were constructed using plastic containers mimicking the natural aquatic habitat of immature Anopheles mosquitoes. Adult mosquitoes that emerged from the mesocosms were collected using a mechanical aspirator. At the end of the experiment, predators were withdrawn from the mesocosms and identified to genus level. Polymerase Chain Reaction (PCR) was employed to identify sibling species of Anopheles gambiae s.l. and to detect Anopheles mosquito DNA in the gut of the predators. Data were analysed using R software. Giant water bugs (belostomatids) were the most aggressive predators of Anopheles larvae, followed by backswimmers (notonectids) and water boatmen (corixids). All female Anopheles gambiae s.l. emerged from the mesocosms were identified as Anopheles arabiensis. Anopheles arabiensis DNA was detected in the gut content of hemipteran specimens analysed from the three families. The number of the adult mosquitoes emerging from the mesocosms was affected by the presence of predators. The findings of this study provide evidence of the potential use of aquatic macroinvertebrate predators as biocontrol agents against immature Anopheles mosquitoes and their potential to be considered as a component of integrated vector management for insecticide resistance and the combined restoration of aquatic ecosystems via smart ecological engineering.

Effect of Microbial Quality of Washing Water on Hand Hygiene Status of Food Handlers in Jimma Town: Implication for Food Hygiene and Safety.

BACKGROUND: In most cases, people pay more attention to the microbial quality of drinking water than the quality of water they used to wash hands. This may lead to the occurrence of various foodborne illnesses through the introduction of pathogenic microbes during preparation and serving of food. OBJECTIVE: To determine the effect of microbial quality of washing water on the hand hygiene status of food handlers in Jimma town. METHODS: Laboratory-based cross-sectional study design was used. A total of 150 food handlers were selected randomly for hand hygiene examination, and 150 water samples were collected aseptically from water storage tanks, food handlers used to wash their hands. The samples were subjected for microbiological analysis using standardized protocol. Descriptive statistics and Pearson correlation coefficient were used to summarize the data and to determine the effect of microbial quality of water on hand hygiene of food handlers, respectively. RESULTS: Among 150 food handlers included in the study, 104 (69.0%) of them were males and 64 (43.0%) of them aged between 35 and 50 years. On the other hand, 64 (42.7%) of the study participants had not attended formal education. About three-fourth of them used stored water to wash their hands, and almost similar proportion of them were waiters. The mean coliform bacteria of water and hand rinsate samples were 4.2 ± 0.8 and 4.1 ± 0.8 log CFU/mL, respectively. CONCLUSION: The study revealed that the microbial quality of water used to wash hands significantly affects the hand hygiene status of the food handlers. Hence, improving the microbial quality of washing water is important to improve the hand hygiene status of food handlers and consequently to prevent the occurrence of food-borne illness in the town.

Microbial quality of raw cow milk and its predictors along the dairy value chain in Southwest Ethiopia.

Raw milk may contain pathogenic microorganism that can seriously affect the health of consumers. In Southwest Ethiopia, raw cow milk is consumed more than the processed products, but its microbiological quality and its predictors are not studied well. The aim of this study was to determine the microbial quality of raw cow milk and its predictors along the dairy value chain in Southwest Ethiopia. A total of 150 milk and 300 environmental samples were collected randomly from dairy farms, milk distribution centers, and retailer outlets for microbiological analysis using standard protocols. One milk handler from each milk production or distribution stage was also interviewed to assess the knowledge, attitude, and practices regarding milk handling. Descriptive statistics and multiple linear regression models were used to summarize the data and to identify predictors of milk microbial quality, respectively. As the milk transported from dairy farm to milk retailer outlet, the mean total bacterial count has increased from 5.0 ±â€¯0.3 to 7.2 ±â€¯0.1 log CFU/ml respectively. The mean coliform count of the milk sample was 4.4 ±â€¯0.4 log CFU/ml at the dairy farm and 7.0 ±â€¯0.2 log CFU/ml at milk selling points, indicating the deterioration of milk quality along the dairy value chain. All of the analyzed water samples were positive for fecal coliform bacteria. The highest coliform bacteria were reported from milk storage equipment found at milk retailer outlet with the count of 4.8 ±â€¯0.5 log CFU/ml. Educational status and attitude of milk handlers and the quality of water used to wash milk equipment and hands of milk handlers were the major factors affecting the microbial quality of raw cow milk. The findings of this study revealed that the microbial quality of raw milk in the study area was poor. Hence, improving the attitude and educational status of milk handlers, and the quality of water is an important step to enhance milk quality and consequently to prevent milk borne diseases.

Bio-Control of Anopheles Mosquito Larvae Using Invertebrate Predators to Support Human Health Programs in Ethiopia.

Mosquitoes have been a nuisance and health threat to humans for centuries due to their ability to transmit different infectious diseases. Biological control methods have emerged as an alternative or complementary approach to contain vector populations in light of the current spread of insecticide resistance in mosquitoes. Thus, this study aimed to evaluate the predation efficacy of selected potential predators against Anopheles mosquito larvae. Potential invertebrate predators and Anopheles larvae were collected from natural habitats, mainly (temporary) wetlands and ponds in southwest Ethiopia and experiments were conducted under laboratory conditions. Optimal predation conditions with respect to larval instar, water volume and number of predators were determined for each of the seven studied predators. Data analyses were carried out using the Poisson regression model using one way ANOVA at the 5% significant level. The backswimmer (Notonectidae) was the most aggressive predator on Anopheles mosquito larvae with a daily mean predation of 71.5 larvae (95% CI: [65.04;78.59]). Our study shows that larval instar, water volume and number of predators have a significant effect on each predator, except for dragonflies (Libellulidae), with regard to the preference of the larval instar. A selection of mosquito predators has the potential to control Anopheles mosquito larvae, suggesting that they can be used as complementary approach in an integrated malaria vector control strategy.