Prevalence and Epidemiological Characteristics of Asymptomatic Malaria Based on Ultrasensitive Diagnostics: A Cross-sectional Study.

BACKGROUND: As the global public-health objectives for malaria evolve from malaria control towards malaria elimination, there is increasing interest in the significance of asymptomatic infections and the optimal diagnostic test to identify them. METHOD: We conducted a cross-sectional study of asymptomatic individuals (N = 562) to determine the epidemiological characteristics associated with asymptomatic malaria. Participants were tested by rapid diagnostic tests (CareStart, Standard Diagnostics [SD] Bioline, and Alere ultrasensitive RDT [uRDT]), loop-mediated isothermal amplification (LAMP), and quantitative reverse transcription polymerase chain reaction (qRT-PCR) to determine malaria positivity. Hemoglobin values were recorded, and anemia was defined as a binary variable, according to World Health Organization guidelines. RESULTS: Compared to reference qRT-PCR, LAMP had the highest sensitivity (92.6%, 95% confidence interval [CI] 86.4-96.5), followed by uRDT Alere Malaria (33.9%, 95% CI 25.5-43.1), CareStart Malaria (14.1%, 95% CI 8.4-21.5), microscopy (5.0%, 95% CI 1.8-10.5), and SD Bioline (5.0%, 95% CI 1.8-10.5). For Plasmodium falciparum specimens only, the sensitivity for uRDT Alere Malaria was 50.0% (95% CI 38.8-61.3) and SD Bioline was 7.3% (95% CI 2.7-15.3). Based on multivariate regression analysis with qRT-PCR as the gold standard, for every 3.2% increase in the prevalence of asymptomatic malaria, hemoglobin decreased by 1 gram per deciliter (prevalence ratio 0.968, 95% CI 0.940-0.997; P = .032). Deletions (4.8%) in hrp2 were noted. CONCLUSIONS: While uRDT Alere Malaria has superior sensitivity to rapid diagnostic tests and microscopy in detecting asymptomatic malaria, LAMP is superior still. Ultrasensitive diagnostics provide the accurate prevalence estimates of asymptomatic malaria required for elimination.

Linking water quality monitoring and climate-resilient water safety planning in two urban drinking water utilities in Ethiopia.

Unsafe drinking water is a recognized health threat in Ethiopia, and climate change, rapid population growth, urbanization and agricultural practices put intense pressure on availability and quality of water. Climate change-related health problems due to floods and waterborne diseases are increasing. With increasing insight into impacts of climate change and urbanization on water availability and quality and of required adaptations, a shift towards climate-resilient water safety planning was introduced into an Ethiopian strategy and guidance document to guarantee safe drinking water. Climate-resilient water safety planning was implemented in the urban water supplies of Addis Ababa and Adama, providing drinking water to 5 million and 500,000 people, respectively. Based on the risks identified with climate-resilient water safety planning, water quality monitoring can be optimized by prioritizing parameters and events which pose a higher risk for contaminating the drinking water. Water quality monitoring was improved at both drinking water utilities and at the Public Health Institute to provide relevant data used as input for climate-resilient water safety planning. By continuously linking water quality monitoring and climate-resilient water safety planning, utilization of information was optimized, and both approaches benefit from linking these activities.

Including aspects of climate change into water safety planning: Literature review of global experience and case studies from Ethiopian urban supplies.

In recent years, the water safety plan approach has been extended towards climate-resilient water safety planning. This happened in response to increasing insight into impacts of climate on drinking-water and required adaptation to anticipated climate change. Literature was reviewed for published guidance and case examples, documenting how to consider climate in water safety planning to support future uptake. Climate-resilient water safety plans were piloted within a project in the water supplies of Addis Ababa and Adama, Ethiopia. Case examples have been published in four of six WHO regions with a focus on urban supplies. Integration of climate aspects focused mostly on the steps of establishing the team, system description, hazard analysis and risk assessment, improvement planning and development of management procedures. While the traditional framework focuses on drinking-water quality, considering climate change augments aspects of water quantity. Therefore, other factors affecting water quantity such as population development and demand of other sectors need to be considered as well. Local climate information and tools should be employed as a significant success factor for future uptake. Such information should be incorporated as it becomes available, and may - depending on the setting - be incrementally integrated into existing water safety plans or used to develop new ones.