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Wind power plays a critical role in supporting Ethiopia's electricity generation, particularly during dry seasons when hydropower availability diminishes. This contribution becomes even more crucial for sustaining industrial growth. However, accurately estimating wind energy remains challenging due to its random and highly variable nature. Deep learning models for time series prediction have been employed to address this issue, and this study evaluates the effectiveness of long short-term memory (LSTM) and gated recurrent unit (GRU) models in predicting wind speed at Adama Wind Farm II in Ethiopia. Model performance was assessed using R2, RMSE, and MAE. GRU significantly outperformed LSTM across all metrics and forecasting horizons. For daily forecasting, GRU achieved an R2 of 0.9727, exceeding LSTM's 0.9062 by 7.34 %, with corresponding RMSE values of 0.0005 and 0.0018, respectively. Similarly, GRU surpassed LSTM's performance for weekly and monthly forecasting. In weekly forecasting, GRU achieved an R2 of 0.9969 compared to LSTM's 0.9930, with RMSE values of 0.0001 for both models. For monthly forecasting, GRU achieved an R2 of 0.9330 compared to LSTM's 0.9303, with corresponding RMSE values of 0.0019 for both models. MAE values also followed the same pattern, with GRU consistently demonstrating lower values than LSTM across all forecasting horizons. These findings advance renewable energy and wind power forecasting research, highlighting the adaptability and versatility of LSTM and GRU models for capturing wind behavior. Decision-makers can use these findings to optimize wind power production, enhance grid operation efficiency, and promote sustainable and cost-effective wind energy. LSTM and GRU models have emerged as powerful tools for precise wind speed and wind power forecasting, which are essential for modern wind energy planning systems. They lay the foundation for a more environmentally friendly and sustainable energy future.

In this paper, the effect of magnon scattering, light–matter coupling strength, temperature, and applied dc field H0 on magnon dispersion, density of magnons, magnetization, and thermodynamic properties of 2D-Sc/GaAs DMS material is studied. The Green function formalism is used to find the magnon dispersion and density in single-mode excitation employing the quantum field theory. Our findings indicate that ferromagnetic phase change is obtained within a limited low-temperature range based on the product Ω0T5/2, which remains below unity and varies with the amount of magnon scattering factor Ω0. It was presumed that the density of localized magnetic impurities can be controlled by taking into account the numerical stability with the number of holes required for mediation, and therefore, a scandium (Sc) dopant and its kind, which have a double functionality of creating holes and adding magnetic impurities from their 3d suborbital, are the best choice to replace those with higher spin magnetic moments. We also observe that the magnetic curves broaden as the temperature further rises and decrease with the enhancement of the magnon scattering factor, perhaps, due to quenching of fermionic spins ceasing the interband excitation. However, in the absence of this factor, the magnetization decreases linearly with the increase in the temperature, breaking the Bloch T3/2 low, perhaps, introducing anomalous condition to such 2D materials. The light–matter coupling strength and the dc field H0 are alleged to be responsible for the formation of the energy gap and variation of magnon dispersion. This work suggests that there is a point above which the temperature TC may not rise with the increase in the impurity concentration x due to magnon scattering, distressing the entire thermodynamic property.

In this paper, the effects of hole doping on the magnon specific heat, average number of magnons, magnetization, and Curie temperature (Tc) of the diluted magnetic semiconductor (DMS) (Ga, Mn)As are theoretically studied using Green function formalism and employing a model system Hamiltonian consisting of magnons, holes, and interactions between magnons and holes. The specific heat capacity of magnons and the number of magnons are found to decrease in the presence of holes and hole–magnon interaction strength, whereas magnetization and Curie temperature (Tc) increase. Our study also reveals that at a constant finite temperature, an increased number of holes lead to a significant increase in magnetization. However, at T = 0, the ground state magnetization value does not exhibit any change with increased free holes and hole–magnon interaction strength. The increased magnetization resulting from doping with holes or electron excitations in this study may present an opportunity to utilize the system under consideration for spintronics purposes at room temperature.

This article investigates the dynamics of spin waves in two sublattice antiferromagnetic (AFM) system spins’ interaction and magnon dispersion relation. The analysis is done starting with a standard model that includes a uniaxial magnetic anisotropy field. Quantum field theory is employed in formulating the problem, and double-time temperature-dependent Green function technique is used to obtain magnon dispersion, whereby random phase approximation is considered to decouple and diagonalize the higher order terms. At low temperatures and long wavelength approximation, dispersion of uniaxial symmetric AFM crystal lattice of metallic fluoride materials, such as MnF2, FeF2, and RbMnF3, is analyzed for illustration. Our findings indicate that as the anisotropic field increases, the magnon dispersion vs wave vector k gradually varies, attempts linearity from being curved, and attains a sinusoidal structure when extended further in the first Brillouin zone. Perhaps, these results are useful to understand the feature of magnon dispersion of stable similar AFM materials for practical application.

Geothermal energy can be used to produce electricity, heat or cool buildings, and other industrial uses. It is a clean and sustainable energy source. It has generated a lot of interest recently because of its several advantages, including its less negative effects on the environment, continuous power generation, low greenhouse gas emissions, and universal accessibility. All of these contribute to geothermal energy becoming a crucial component of the world's environmentally friendly energy production. Ethiopia has access to a wide variety of renewable energy sources, including a sizable geothermal energy potential with the capacity to produce over 10,000 megawatts of electricity. The Great Rift Valley runs 1,000 km from the Red Sea-Gulf of Aden junction in the northwest to the Turkana Depression in the south, provides access to the Rift Valley's enormous geothermal energy to the nation. Only 7.3 MW of electricity are currently produced from geothermal resources in Ethiopia. Even though the usage of this resource is still in its infancy, Ethiopia has a considerable potential for it. The expansion of geothermal energy in the country is being driven by the need to diversify hydropower into other renewable energy sources, as well as an imbalance in energy demand and supply in the country. However, there are few thorough analyses of geothermal energy's potential, challenges, and technological advances. This review article provides a detailed evaluation of Ethiopia's geothermal energy potential, challenges, and future prospects. The most recent data was gathered from published papers and various types of literature. The study recommends making considerable use of nation's geothermal energy potential as alternative energy technology with minimal impact on both the environment and the socioeconomic system. The study not only revealed the country's geothermal energy potential, but also the challenges and potential solutions to the issue of expanding this energy system. Furthermore, the most effective ways for producing and utilizing geothermal energy sources were looked into, along with some perspectives based on the difficulties associated with the efficient use of geothermal energy in Ethiopia. Although this study primarily provides information about Ethiopia's geothermal energy, in our opinion it could also be helpful to other countries within the East African region.

Due to an increase in fuel demand and efforts to lessen greenhouse gas (GHG) emissions, countries around the globe are searching for different clean energy sources such as biodiesel. Biodiesel is a renewable energy source that appears to be an ideal solution to meet global energy needs, including in Ethiopia. Ethiopia imports liquid fuels to meet its demands, although there are initiatives to extend the nation's energy supply through the use of biofuels. However, comprehensive assessments of biodiesel's potential, challenges, and production technologies are lacking. This review aimed to explore the technological advancement, opportunities, challenges, and prospects of using biodiesel in Ethiopia. The latest data from governmental reports and several articles published in reputable journals were used as sources. Transesterification, which involves the reaction of oil/fat with alcohol in the presence of a catalyst, is a standard procedure for producing biodiesel. The high biodegradability, minimal toxicity, and almost zero emissions are unique characteristics of biodiesel. Therefore, biodiesel can substitute fossil fuels in numerous applications, including transportation and internal combustion engines, without requiring major retrofits, and appears to improve the rural economic potential and environmental protection. The results of many studies have shown that the combustion features and the engine power output of biodiesel were comparable to that of fossil fuel diesel. Alternative energy sources like biodiesel should be employed to meet the growing demand mainly in the transportation sector. Ethiopia has a huge biodiesel potential due to the existence of many biofuel crops. Imports of petroleum-based fuel will be reduced if all players in the energy sector collaborate to promote the production of biodiesel from a variety of sustainable feedstocks. This can be accomplished by adopting existing biodiesel technologies, developing biodiesel regulations/policies, funding biodiesel research initiatives, etc. Overall, biodiesel could be a way better solution to supplant diesel for Ethiopia's varied demands. We believe that the findings presented in this article will highlight Ethiopia's current and future prospects for biodiesel deployment.

Ternary boron-carbon-nitride compounds are the hardest, chemically stable, and most applicable semiconductors in optoelectronic devices. We investigate the quasi-particle and excitonic properties of type II o-BC2N using many-body perturbation theory (MBPT). The state-of-the-art GW and BSE methods were used to determine the accurate band gap and excited-state characteristics of this material. We simulate the convergence test and structural optimization in DFT, which is the starting point for the GW calculation. We also compute the convergence test of the parameters in GW and BSE. As a result, the bandgap of our system is found to be 2.31 eV and 1.95 eV using the GW approximation and DFT-PBE, respectively. Since the valence and conduction band edges are located at different Brillouin zones, we decide that o-BC2N is an indirect bandgap semiconductor. In addition, by applying the scissor operator, we corrected the quasi-particle bandgap, which shows almost the same result as the GW approximation. Furthermore, using the BSE algorithm, we calculate the optical bandgap of type II o-BC2N to be 4.0 eV with the excitonic effect and 4.4 eV without the excitonic effect. The highest peaks of the imaginary dielectric function with the excitonic effect shift to a lower energy level at 11 eV than without the excitonic effect at 13.5 eV. The electron charge distribution is computed by fixing the hole position. Finally, we suggest that type II o-BC2N is promising for the application of optoelectronic semiconductors.

To provide rural communities with low-cost electricity, innovative off-grid renewable energy producing techniques have emerged. The International Energy Agency estimates that around 45% of Ethiopia’s total population have access to electricity. Nearly 85% of Ethiopia’s urban population has access to public electricity, but this figure is only 29% for the rural population. This study examines the feasibility of using combined photovoltaic (PV)/diesel/battery systems to power a remote rural school in southern Ethiopia. The performance of various hybrid systems was assessed using techno-economic and environmental analyses, and the optimal solution was chosen using the Hybrid Optimization Model for Electric Renewable (HOMER) analytic tool. The evaluation criteria include net present cost (NPC), cost of energy (COE) and emissions. The results indicate that PV/DG/battery hybrid energy system (HES) with a 7.5 kW PV, 7.3 kW DG, 6.60 kW converter, and 11 units of batteries (case I) is the most feasible, optimized, cost-effective and environmentally friendly system among the systems considered. This system has a Net Present Cost (NPC) of $32,019 and a Cost of Energy (COE) of $0.254/kWh, as computed using current equipment values. The optimized system is also environmentally benign, emitting 793 kg of carbon dioxide per year, about 91% less than the PV/diesel combination (worst case IV). Furthermore, sensitivity analysis was performed to examine the impacts of altering factors such as solar radiation, fuel price, and battery minimum state of charge (SOCmin) on system cost and performance. We believe that the information given in this paper will shed light on the current state and future prospects for renewable energy deployment in Ethiopia, and also show that, if policymakers create the necessary investment environment, such projects can be a viable alternative to rural electrification.

Solar energy is one of the renewable energy sources that can be used to solve Ethiopia’s current energy problems. However, global solar radiation data for the country are either not available at all levels or recorded for only a few years at some locations. In this study, monthly mean daily global solar radiation (H) over the horizontal surface at 15 sites in Ethiopia was calculated using sunshine hour-based models, such as the Angstrom-Prescott model (AP), the Louche model (LO), and the Glover-McCulloch Estimation Model (GM). For the performance of the proposed model, statistical error analysis and geospatial results were performed to ensure the validity of the model used. The validation results show that the H estimates from all stations agree well with the measured data from all models. Therefore, the proposed model can be used to predict global solar radiance. However, among the other models, the GM model performed the best H estimates for all sites, with an average r of 0.9574, an average RMSE of 0.6017, an average MPE of 0.00335, and an average MBE of −0.7555, respectively. Therefore, the GM model is suitable for estimating global insolation for the entire country. The highest measured solar radiation value (from NASA) was recorded in February (6.89 kWh/m2/day). Likewise, the highest estimated global solar irradiance in February was observed using the three empirical models, with values of 7.55, 7.12, and 7.47 kWh/m2/day for the AP, LO, and GM models, respectively. The lowest measured and calculated radiation values were recorded in July due to the country’s highest cloud cover and rainy season. The results also show that the estimated H in Ethiopia ranges from 3.45 6.89 kWh/m2/day (July) to 7.47 6.89 kWh/m2/day (February) based on the GM model calculations, with an annual average of 5.83 kWh/m2/day (average across all sites). This study can be utilized in the design, analysis and performance evaluation of solar energy potential, which is gaining significant attention from the Ethiopian government in the advocacy of a green economy and reducing greenhouse gas emissions as one of its political agendas to meet the Sustainable Development Goal (SDG).

The superconductivity of Rhenium Beryllium in two band model is theoretically studied using a standard model Hamiltonian which contains the Bardeen, Cooper and Schriefer, BCS type pairing interaction. Green function formalism was employed to obtain expression for superconducting order parameter in the bands, the coupling parameters and the superconducting critical temperature, T _C , for this ReBe _22 material. Our findings indicate, the enhancement of the superconducting critical temperature with the augmentation of the electron-phonon coupling strength in the entire system. The variation of the coupling parameter in the bands is understood as the reason for introducing a temperature gap and rising of the critical temperature suggesting significant upsurge at further scrutiny.

Adinew Zewdu Chernet,1 Kassu Dasta,2 Feleke Belachew,3 Baharu Zewdu,4 Mengistu Melese,5 Musa Mohammed Ali6 1Oromia Public Health Laboratory, Adama, Ethiopia; 2College of Health Science, School of Medical Laboratory Science, Addis Ababa University, Addis Ababa, Ethiopia; 3International Centers for AIDS Care and Treatment Program (ICAP), Addis Ababa, Ethiopia; 4Washington Medical Center, Addis Ababa, Ethiopia; 5Adama Hospital Medical College, Adama, Ethiopia; 6College of Medicine and Health Sciences, School of Medical Laboratory Science, Hawassa University, Hawassa, EthiopiaCorrespondence: Adinew Zewdu Chernet Email adinewz@yahoo.comIntroduction: Healthcare-associated infection (HCAI) is a type of infection that is acquired while receiving healthcare services in a hospital or other healthcare settings. The objective of this study was to determine the incidence of HCAI and associated factors at Adama Hospital Medical College (AHMC), Adama city, Ethiopia.Method: A hospital-based longitudinal study was conducted among 300 participants at AHMC from February to May 2017. The study participants’ clinical characteristics were collected using a structured interview and clinical evaluations. Data were analyzed by descriptive statistics using SPSS software version 20. Various clinical samples collected from participants were processed and bacteria were isolated by using standard microbiological methods recommended by the World Health Organization.Result: The total incidence rate of HCAI was 9.7 [95% CI: 7.1– 12.9] cases per 1000 persons-days. Specific incidence rates were as follows: 8 cases per 1000 person-days [95% CI: 08.74, 20.66] for surgical site infections; 60.2 cases per 1000 device-days [95% CI: 33.47, 100.3] for catheter-associated urinary tract infections; 1.4 cases per 1000 device-days [95% CI: 0.06752, 6.656] for catheter-associated bloodstream infections; 14.1 cases per 1000 device-days [95% CI: 0.7047, 69.46] for ventilator-associated pneumonia; 73.5 cases per 1000 person-days [95% CI: 26.94, 163] for non-surgical skin break infections and 0.6 cases per 1000 person-days [95% CI: 0.02906, 2.864] for antibiotic-associated diarrhea. Most of the infections were caused by Gram-negative bacteria. Renal disease and type 2 diabetes mellitus were significantly associated with HCAI (P< 0.05).Conclusion: HCAI was predominant in this study. The major contributing factors for HCAI at AHMC were renal disease and type 2diabetes mellitus.Keywords: healthcare-associated infection, risk factors, Adama Hospital Medical College, Ethiopia

This article reports the crystal structure, impurity formation energy, electronic property, magnetic property, and dopant configuration site dependence of ferromagnetic temperature Tc of anatase (Ti15FeO32, Ti14Fe2O32, and Ti13Fe3O32) by first-principles calculations based on density functional theory (DFT) with Hubbard onsite correction (DFT+U). The estimated formation energy validated the structural stability of the Fe-doped TiO2 with 2.08% (Ti15FeO32), 4.17% (Ti14Fe2O32), and 6.25% (Ti13Fe3O32) concentrations at the Ti sites. The electronic structure analysis reveals that the bandgap in the doped system changed from a wide bandgap of 3.23 eV (pristine TiO2) to slightly lower bandgaps of 3.13, 3.08, and 3.04 eV with Fe concentrations of 2.08%, 4.17%, and 6.25%, respectively. The calculated partial density of states also show the hybridization of O with 2p- and Fe 3d-orbitals near the conduction band minimum and generate the impurity energy level reducing the bandgap. Furthermore, the estimated Curie temperature (Tc) varied depending on the Fe–Fe interactions, the concentration of the Fe dopants, and doping sites. For instance, Tc is calculated to be 343.57 K for 2.08% Fe at the symmetric point of the crystal while estimated to be 323.84 and 393.297 K for 4.17% at the nearest neighbor and the next-nearest neighbor configurations. Due to the increase of the Fe concentration to 6.25%, the calculated Tc monotonically improved to 342.5 and 513.174 K at the nearest neighbor and the next-nearest neighbor of the Fe-site, respectively. These indicate that all the calculated findings estimate the ferromagnetic transition temperature Tc to above room temperature. Moreover, the system’s total magnetization reveals the augmentation of a number of unpaired electrons as a result of rise in oxygen vacancies and, hence, there could be more holes when the Fe content gets higher, perhaps generating more bound magnetic polarons that favor the critical temperature, Tc.

This article reports polymer solar cell performance evaluated using general-purpose photovoltaic device model (GPVDM) software for various device structures. The essential parameters of the cell such as short circuit current density (JSC), open-circuit voltage (VOC), fill factor (FF), and power conversion efficiency (PCE) are evaluated for these structures. The simulation result shows the performance of the cells could be highly affected by both interfacial and active layers. Among the demonstrated device structures, better performance is observed for device structure ITO/V2O5/PTB7 : PC70BM/TiOx/Al with 10.4 mA/cm2 short circuit current density, 0.89 V open-circuit voltage, 59.5% fill factor, and 6.1% power conversion efficiency. The study is useful for a better understanding of the powerful effect of the materials in the device structure on the performance of the cell and thereby determines the proper device structure and materials for improving the performance of the cell.

This article reports effects of magnon-exciton interaction on magnetic ordering in diluted magnetic semiconductors (DMS). Quantum field theory is employed using the double time temperature dependent Green function technique to obtain dispersion. It is understood that interaction of the two quasi particles take place in the exciton cloud and consequently the spontaneously ordered localized electrons might be partly trapped and subjected to different angular precision resulting in increase ofthe number of magnons. According to our analysis the exciton-magnon coupling phenomena may be the reason for the attenuation of spontaneous magnetization and ferromagnetic transition temperature Tc. Further observations indicate that there is a significant departure of magnetic impurity concentration, xm, vs. Tc relation from the linearity as suggested by electronic calculations and experimental estimations near absolute zero temperature.

The dream of realizing room temperature superconductivity is one of the most challenging problems in condensed matter physics. Currently, materials with dense hydrogen contents at high pressures hold great promise for realizing room temperature superconductivity. In particular, pressurized alkaline earth metal hydrides received particular attention following the recently predicted sodalite-like calcium hydride (CaH _6 ) with predicted Tc about 261 K above a pressure of 150 GPa; and magnesium hydride (MgH _6 ) with predicted Tc about 270 K above 300 GPa. In this paper, we studied magnesium hydride (MgH _4 ) with tetragonal (I4/mmm) type symmetry, and we found that this structure shows the highest ${T}_{c}\cong 313K$ at a pressure of 280 GPa which is higher than that of MgH _6 . Using density-functional perturbation theory (DFPT), the superconducting transition temperature, electron-phonon coupling, Eliashberg spectral function, and the logarithmic average frequency were computed. Our results reveal that, the computed values are reasonably in agreement with previous estimates.

Using ortho-atomic Hubbard-corrected density functional theory, we present magnetic properties, ferromagnetic transition temperature T _c , Neel temperature T _N , electronic structure, structural formation energy, and crystal structure of anatase (Ti _16− _x Mn _x O _32 for x = 1, 2, 3, 4 and 6). According to the calculated formation energy, an oxygen-rich condition is more structurally stable than a Ti-rich situation. The geometric and lattice parameter optimization result indicates that Mn ^2+ exists in the system. In addition, when Mn is substituted in the system, some of the bonds that connect oxygen with the Mn ion are broken, and the bond lengths show variation; this results in defects, which cause the formation of oxygen vacancies that enhance both ferromagnetic and antiferromagnetic properties of the system. According to the structure of electronic bands and PDOS analysis, 2p and 3d hybridization lead to a decrease in the edge of the CB and an increase in the edge of the VB, narrowing the bandgap from 3.23 eV to 2.21 eV(for 4.17% of Mn), 2.13 eV (for 8.33% of Mn) and 1.69 eV (for 12.5% of Mn). Results also showed that both ferromagnetic and antiferromagnetic properties are energetically favored. Furthermore, the material exhibits antiferromagnetic with predicted T _N to be 804.13 K for a small concentration of Mn dopant (for 4.17% of Mn), which is higher than room temperature. In contrast, the calculated ferromagnetic temperature (T _c ) was increased from 255.42 K (for 8.33% of Mn) to 385.63 K (for 12.5% of Mn), most likely as a cause of bound magnetic polarons (BMPs) production. Result also reveals oxygen vacancy for the relaxed pristine (Ti _16 O _31 ) a non-zero magnetic moment and a total magnetization of 2.00 μ _B which is observed as a result of an ortho-atomic projector. The present findings suggest that TiO _2 could be tailored through doping and oxygen vacancy for versatile spintronic applications, inconsistent with previous experimental results.

Starting with a Kondo lattice model type Hamiltonian, the effects of the magnetic field, electric field, and magnetic anisotropic energy on the magnetic properties of the Fe/GaSb diluted magnetic semiconductor are studied. The analytical technique is employed to analyze magnon dispersion, magnetization, and critical temperature, Tc. The enhancement of the temperature with increasing impurity concentration x and/or with the magnetic field and electric field is established, which is in good agreement with recent experimental observations. It is clearly shown that magnon dispersion and magnetization can be controlled with these fields applied, magnetic anisotropic energy, and impurity concentration alternatively or all together. Due to the inclusion of the magnetic anisotropic energy, we could identify a significant escalation of magnon dispersion/bandgap energy and a slight reduction of magnetization.

This article reports magnetization and specific heat capacity anomalies in one dimensional diluted magnetic semiconductors observed at very low temperatures. Based on quantum field theory double time temperature dependent Green function technique is employed to evaluate magnon dispersion and the time correlation function. It is understood that magnon-photon coupling and magnetic impurity concentration controls both, such that near absolute temperature magnetization is nearly zero and abruptly increase to saturation level with decreasing magnon-photon coupling strength. We also found out dropping of magnetic specific heat capacity as a result of increase in magnetic impurity concentration x, perhaps because of inter-band disorder that would suppress the enhancement of density of spin waves.

BackgroundWHO promotes the SAFE strategy for the elimination of trachoma as a public health programme, which promotes surgery for trichiasis (ie, the S component), antibiotics to clear the ocular strains of chlamydia that cause trachoma (the A component), facial cleanliness to prevent transmission of secretions (the F component), and environmental improvements to provide water for washing and sanitation facilities (the E component). However, little evidence is available from randomised trials to support the efficacy of interventions targeting the F and E components of the strategy. We aimed to determine whether an integrated water, sanitation, and hygiene (WASH) intervention prevents the transmission of trachoma.MethodsThe WASH Upgrades for Health in Amhara (WUHA) was a two-arm, parallel-group, cluster-randomised trial in 40 rural communities in Wag Hemra Zone (Amhara Region, Ethiopia) that had been treated with 7 years of annual mass azithromycin distributions. The randomisation unit was the school catchment area. All households within a 1·5 km radius of a potential water point within the catchment area (as determined by the investigators) were eligible for inclusion. Clusters were randomly assigned (at a 1:1 ratio) to receive a WASH intervention either immediately (intervention) or delayed until the conclusion of the trial (control), in the absence of concurrent antibiotic distributions. Given the nature of the intervention, participants and field workers could not be masked, but laboratory personnel were masked to treatment allocation. The WASH intervention consisted of both hygiene infrastructure improvements (namely, construction of a community water point) and hygiene promotion by government, school, and community leaders, which were implemented at the household, school, and community levels. Hygiene promotion focused on two simple messages: to use soap and water to wash your or your child's face, and to always use a latrine for defecation. The primary outcome was the cluster-level prevalence of ocular chlamydia, measured annually using conjunctival swabs in a random sample of children aged 0-5 years from each cluster at 12, 24, and 36 month timepoints. Analyses were done in an intention-to-treat manner. This trial is ongoing and is registered at ClinicalTrials.gov, NCT02754583.FindingsBetween Nov 9, 2015, and March 5, 2019, 40 of 44 clusters assessed for eligibility were enrolled and randomly allocated to the trial groups (20 clusters each, with 7636 people from 1751 households in the intervention group and 9821 people from 2211 households in the control group at baseline). At baseline, ocular chlamydia prevalence among children aged 0-5 years was 11% (95% CI 6 to 16) in the WASH group and 11% (5 to 18) in the control group. At month 36, ocular chlamydia prevalence had increased in both groups, to 32% (24 to 41) in the WASH group and 31% (21 to 41) in the control group (risk difference across three annual monitoring visits, after adjustment for prevalence at baseline: 3·7 percentage points; 95% CI -4·9 to 12·4; p=0·40). No adverse events were reported in either group.InterpretationAn integrated WASH intervention addressing the F and E components of the SAFE strategy did not prevent an increase in prevalence of ocular chlamydia following cessation of antibiotics in an area with hyperendemic trachoma. The impact of WASH in the presence of annual mass azithromycin distributions is currently being studied in a follow-up trial of the 40 study clusters. Continued antibiotic distributions will probably be important in areas with persistent trachoma.FundingNational Institutes of Health-National Eye Institute.TranslationFor the Amharic translation of the abstract see Supplementary Materials section.

BackgroundCurrent guidelines recommend community-wide mass azithromycin for trachoma, but a targeted treatment strategy could reduce the volume of antibiotics required.MethodsIn total, 48 Ethiopian communities were randomized to mass, targeted, or delayed azithromycin distributions. In the targeted arm, only children aged 6 months to 5 years with evidence of ocular chlamydia received azithromycin, distributed thrice over the following year. The primary outcome was ocular chlamydia at months 12 and 24, comparing the targeted and delayed arms (0-5 year-olds, superiority analysis) and the targeted and mass azithromycin arms (8-12 year-olds, noninferiority analysis, 10% noninferiority margin).ResultsAt baseline, the mean prevalence of ocular chlamydia in the 3 arms ranged from 7% to 9% among 0-5 year-olds and from 3% to 9% among 8-12 year-olds. Averaged across months 12-24, the mean prevalence of ocular chlamydia among 0-5 year-olds was 16.7% (95% confidence interval [CI]: 9.0%-24.4%) in the targeted arm and 22.3% (95% CI: 11.1%-33.6%) in the delayed arm (P = .61). The final mean prevalence of ocular chlamydia among 8-12 year-olds was 13.5% (95% CI: 7.9%-19.1%) in the targeted arm and 5.5% (95% CI: 0.3%-10.7%) in the mass treatment arm (adjusted risk difference 8.5 percentage points [pp] higher in the targeted arm, 95% CI: 0.9 pp-16.1 pp higher).ConclusionsAntibiotic treatments targeted to infected preschool children did not result in significantly less ocular chlamydia infections compared with untreated communities and did not meet noninferiority criteria relative to mass azithromycin distributions. Targeted approaches may require treatment of a broader segment of the population in areas with hyperendemic trachoma.

The Trachoma Control Program in Amhara region, Ethiopia, scaled up the surgery, antibiotics, facial cleanliness, and environmental improvement (SAFE) strategy in all districts starting in 2007. Despite these efforts, many districts still require additional years of SAFE. In 2017, four districts were selected for the assessment of antibody responses against Chlamydia trachomatis antigens and C. trachomatis infection to better understand transmission. Districts with differing endemicity were chosen, whereby one had a previous trachomatous inflammation-follicular (TF) prevalence of ≥ 30% (Andabet), one had a prevalence between 10% and 29.9% (Dera), one had a prevalence between 5% and 10% (Woreta town), and one had a previous TF prevalence of < 5% (Alefa) and had not received antibiotic intervention for 2 years. Survey teams assessed trachoma clinical signs and took conjunctival swabs and dried blood spots (DBS) to measure infection and antibody responses. Trachomatous inflammation-follicular prevalence among children aged 1-9 years was 37.0% (95% CI: 31.1-43.3) for Andabet, 14.7% (95% CI: 10.0-20.5) for Dera, and < 5% for Woreta town and Alefa. Chlamydia trachomatis infection was only detected in Andabet (11.3%). Within these districts, 2,195 children provided DBS. The prevalence of antibody responses to the antigen Pgp3 was 36.9% (95% CI: 29.0-45.6%) for Andabet, 11.3% (95% CI: 5.9-20.6%) for Dera, and < 5% for Woreta town and Alefa. Seroconversion rate for Pgp3 in Andabet was 0.094 (95% CI: 0.069-0.128) events per year. In Andabet district, where SAFE implementation has occurred for 11 years, the antibody data support the finding of persistently high levels of trachoma transmission.

The WHO recommends improving access to water as part of a comprehensive strategy for elimination of trachoma as a public health problem; however, this recommendation is not based on evidence from randomized trials. In a region of Ethiopia with hyperendemic trachoma, seven communities were randomized to a hand-dug well (HDW) and seven communities to no intervention to determine the impact of HDWs on the community prevalence of ocular chlamydia infection (primary prespecified outcome). All communities continued to receive government hygiene and sanitation services and outreach. Participants were not masked, given the nature of the intervention, but laboratory personnel were masked to treatment allocation. Hand-dug wells were successfully built in six of the seven communities; five of these wells were still functional at the conclusion of the trial. At the end of the trial, an average of 74% of households reported traveling < 30 minutes to collect water in the HDW arm, compared with 45% in the control arm, and the daily volume of water used for hygiene was similar (e.g., mean of 0.7 L per person in each arm). The pseudo-median prevalence of ocular chlamydia among 0- to 5-year old children at the 24-month visit was 23% in the HDW group and 13% in the control group (P > 0.99). This small cluster-randomized trial provided no evidence to suggest that simply constructing HDWs, in the absence of other hygiene promotion activities, is effective for reducing transmission of ocular chlamydia.

Nucleic acid amplification tests are increasingly used to detect ocular chlamydia infection in trachoma research and programs. To evaluate the reliability of Chlamydia trachomatis detection by the Abbott RealTime CT/NG assay (Abbott Molecular, Inc., Des Plaines, IL) on the m2000 platform, three conjunctival samples were collected from each of 200 children aged 0-9 years in Ethiopia: two from the right eye and one from the left eye. Four aliquots were processed for each child: two from the first right eye sample, one from the second right eye sample, and one from the left eye sample. Sixty-nine swabs were processed in a U.S. laboratory and 131 in an Ethiopian laboratory. Intra-class correlation coefficients (ICCs) were high when comparing two aliquots from the same swab (ICC ranged from 0.96 to 0.99), two separate swabs from the right eye (0.89-0.91), and one right and one left eye swab (0.87-0.89), indicating reliable chlamydial load assessment across different samples and laboratory settings.

BACKGROUND:After approximately 5 years of SAFE (surgery, antibiotics, facial cleanliness, environmental improvement) interventions for trachoma, hyperendemic (trachomatous inflammation-follicular (TF) ≥30%) districts remained in Amhara, Ethiopia. This study's aim was to characterize the epidemiology of Chlamydia trachomatis (Ct) infection and load among pre-school aged children living under the SAFE strategy. METHODS:Conjunctival swabs from a population-based sample of children aged 1-5 years collected between 2011 and 2015 were assayed to provide Ct infection data from 4 endemic zones (comprised of 58 districts). Ct load was determined using a calibration curve. Children were graded for TF and trachomatous inflammation-intense (TI). RESULTS:7,441 children were swabbed in 4 zones. TF and TI prevalence were 39.9% (95% confidence Interval [CI]: 37.5%, 42.4%), and 9.2% (95% CI: 8.1%, 10.3%) respectively. Ct infection prevalence was 6.0% (95% CI: 5.0%, 7.2%). Infection was highest among children aged 2 to 4 years (6.6%-7.0%). Approximately 10% of infection occurred among children aged 1 year. Ct load decreased with age (P = 0.002), with the highest loads observed in children aged 1 year (P = 0.01) vs. aged 5 years. Participants with TF (P = 0.20) and TI (P