The emergence and spread of insecticide resistance in the major African malaria vectors Anopheles gambiae (s.s.) and An. arabiensis may compromise the current vector control interventions and threatens the global malaria control and elimination efforts. Insecticide resistance was monitored in several study sites in Ethiopia from 2013 to 2015 using papers impregnated with discriminating concentrations of DDT, deltamethrin, bendiocarb, propoxur, malathion, fenitrothion and pirimiphos-methyl, following the WHO insecticide susceptibility test procedure. Mosquitoes sampled from different localities for WHO bioassay were morphologically identified as An. gambiae (s.l.) using standard taxonomic keys. Samples were identified to species using species-specific polymerase chain reaction (PCR) and screened for the presence of target site mutations L1014F, L1014S and N1575Y in the voltage gated sodium channel (VGSC) gene and G119S in the acethylcholinesterase (AChE) gene using allele-specific PCR. Biochemical assays were performed to assess elevated levels of acetylcholinesterases, carboxylcholinesterases, glutathione-S-transferases (GSTs) and cytochrome P450s monooxygenases in wild populations of An. arabiensis, compared to the fully susceptible Sekoru An. arabiensis laboratory strain. Populations of An. arabiensis were resistant to DDT and deltamethrin but were susceptible to fenitrothion in all the study sites. Reduced susceptibility to malathion, pirimiphos-methyl, propoxur and bendiocarb was observed in some of the study sites. Knockdown resistance (kdr L1014F) was detected in all mosquito populations with allele frequency ranging from 42 to 91%. Elevated levels of glutathione-S-transferases (GSTs) were detected in some of the mosquito populations. However, no elevated levels of monooxygenases and esterases were detected in any of the populations assessed. Anopheles arabiensis populations from all surveyed sites in Ethiopia exhibited resistance against DDT and pyrethroids. Moreover, some mosquito populations exhibited resistance to propoxur and possible resistance to bendiocarb. Target site mutation kdr L1014F was detected in all mosquito populations while elevated levels of glutathione-S-transferases (GSTs) was detected in some mosquito populations. The reduced susceptibility of An. arabiensis to propoxur and bendiocarb, which are currently used for indoor residual spraying (IRS) in Ethiopia, calls for continuous resistance monitoring, in order to plan and implement evidence based insecticide resistance management.

Population resettlement has been considered among factors that may increase risk of malaria transmission. This study reports, the impact of resettlement on malaria incidence and entomological indices among communities resettled in suburbs of Jimma town, southwestern Ethiopia. A cohort of 604 study participants (302 resettlers and 302 non-resettlers) was monthly followed-up from September to November 2013 using active case detection. Moreover, longitudinal entomological study was conducted from June to November 2013. Anopheline mosquitoes were collected using CDC light traps and pyrethrum spray catches. Sporozoite ELISA was performed to determine Plasmodium infection rates. Overall, 112 malaria cases were recorded during the three-month follow-up, of which 74.1% of the cases were from resettlement villages. Plasmodium falciparum incidence from resettlement and non-resettlement villages was 52.5 and 14.5/1,000 person-months at risk, respectively. Resettlement villages were three times at higher risk of Plasmodium infection (OR = 2.8, 95% CI: 1.22-6.48). Anopheles gambiae s.l. was the predominant (86.6%) of all the collected anopheline mosquito species. Plasmodium sporozoite rate in the resettlement and non-resettlement villages was 2.1 and 0.72%, respectively. Plasmodium falciparum entomological inoculation rate (EIR) for An. gambiae s.l. in the resettlement and non-resettlement villages was 13.1 and 0 infective bites/person/night, respectively. Both sporozoite rate and EIR were significantly higher in the resettlement villages (p < 0.05). Resettled communities were at higher risk of malaria infection as compared to non-resettled communities. Special attention should be given to malaria control interventions during resettlement programmes.

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.

Increasing clean energy access for the rural population of developing countries is a priority to meet the United Nation’s Sustainable Development Goals-Zero hunger and affordable modern/clean energy for all. Similarly, to meet this goal, Ethiopia moved towards the development of renewable energy. However, there is a limited knowledge on the biomass energy potential for biogas technology adoption at the local/district level. Thus, this study aimed at assessing the biomass energy potential for biogas technology adoption and its determinant factors among rural households in Limmu Kossa district, Ethiopia. Data was collected from 411 households from 13–24 June 2021. The quantitative data was analyzed using Statistical software Package for Social Science (SPSS) version 23 and Microsoft Word-Excel. The qualitative data was analyzed using content analysis. The study showed that over 96% of households rely on the traditional use of biomass energy for cooking. Nevertheless, on average, about 1 m³ of biogas energy can be potentially available from livestock dung and human excreta per household per day. However, the huge potential of biomass energy did not contribute to improved energy technologies such as biogas. The adoption of biogas is hampered by the non-functionality of the installed biogas, a lack of awareness, the availability of firewood, and the socio-economic characteristics of the households. Thus, improving the awareness of the community, arranging financial access, and training biogas technicians, especially from the local community, would increase the adoption of the technology. However, meeting the digester water demand with the water collected from the walking distances of 15–20 min can be challenging. Community-based biogas digesters or biogas involving income generation with a water supply around the digester would be a better and more sustainable option for biogas energy adoption and use.

Freshwater ecosystems in rapidly urbanizing regions are increasingly threatened by effluent discharges. Car-wash stations are a significant source of pollution, releasing effluents rich in detergents, oils, and organic matter directly into streams. Despite global evidence demonstrating the effects of car-wash effluent on receiving water bodies, it remains overlooked in Ethiopia. This study assessed the impact of car-wash effluent on water quality and habitat condition of urban streams in Jimma city, Ethiopia. The study was conducted at seven car-wash stations in April 2023. Forty-two water samples were collected from upstream, discharge, and downstream sites during weekdays and weekends and analyzed for different physicochemical quality parameters. Habitat integrity was evaluated using the USEPA rapid bioassessment protocol. Principal component analysis (PCA) was applied to identify water quality variation among stream sites. This study revealed deteriorated water quality at discharge points, with significantly higher mean values for turbidity (483.3 ± 193.5 NTU), total suspended solids (TSS) (561.0 ± 460.9 mg/L), and 5-day biochemical oxygen demand (BOD₅) (333.6 ± 104.5 mg/L) and with lower dissolved oxygen (DO) record (4.7 ± 1.5 mg/L) compared to upstream sites (p < 0.05). Higher BOD₅, orthophosphate, nitrate, and water temperature were recorded during weekends compared to weekdays. PCA results showed that discharge points were associated with elevated turbidity, TSS, BOD₅, and orthophosphate, which are inversely correlated with DO. Habitat scores classified most discharge points as poor and several downstream sites as marginal, suggesting ecological stress consistent with car-wash effluent impacts. These findings indicate a need for targeted monitoring and regulatory attention to uncontrolled car-wash wastewater discharge.

Background In developing countries, poor waste management causes widespread heavy metal and toxic chemical contamination, threatening vulnerable populations. Objective This systematic review of the health risks of waste-related heavy metals and toxic chemicals among vulnerable populations in low- and middle-income (LMICs) countries synthesizes multifaceted exposure pathways, clinical biomarker data, and localized risk thresholds. Methods PubMed, Scopus, ScienceDirect, and ProQuest databases were searched for peer-reviewed studies published in English between 2012 and 2025. Out of the 731 records identified, two independent reviewers extracted data and appraised the quality of 21 eligible studies using Joanna Briggs Institute (JBI) Critical Appraisal Checklist, with initial variances successfully resolved via a formal consensus protocol. Results Primary contaminants identified were Pb, Cd, Cr, As, Hg, and Ni. Exposure pathways included soil and dust ingestion, inhalation of contaminated emissions, dermal absorption, occupational contact. Pediatric cohorts face extreme risks through ingestion and inhalation; mean blood lead reached 60.43 µg/L, breaching the World Health Organization 50 µg/L threshold, and correlated with a Full-Scale IQ decline (β= − 18.42, p < 0.05). Risk modeling showed pediatric non-carcinogenic vulnerabilities exceeded the US EPA Hazard Index baseline of 1.0 (e.g., Mn HI = 1.69), while total carcinogenic risk reached concerning level (10^–5). Occupational biomarkers tracked hair mercury up to 10.8 mg/kg in miners and mean blood cyanide at 400 µg/L. Conclusion Toxic waste exposures drive severe, unequal neurological, renal, hepatic, and carcinogenic burdens across LMICs. Mitigating these risks requires operationalized policies including enforcement of the Basel convention, mandatory provision of N95/P100 respirators and nitrile gloves, annual blood lead screenings, and formalizing labor contracts via Extended Producer Responsibility models.