Evaluation of a Digital Microscope for Malaria
MalariaLight microscopy, which is based on century-old technology, remains a key indicator in drug efficacy testing performed in the context of clinical trials for monitoring existing antimalarial drugs or in the context of regulatory clinical trials for registration of new drugs. It is one of the main diagnostic methods for malaria diagnosis in general, as in an ideal setting it can provide low-cost accurate diagnosis, determine the density of parasites in the blood, and accurately differentiate between different malaria parasite species, characteristics vital to the implementation of global plans for drug efficacy monitoring. Malaria rapid tests (RDTs), while useful for rapid diagnosis and case management, do not provide information on the parasite density nor the species differentiation necessary for research and drug efficacy assessment. Microscopy therefore retains key advantages over a number of newer technologies, but its reliability is severely impeded by dependence on high technical competence of the human operators as well as availability of high quality equipment and reagents. Recent studies have demonstrated frequent poor specificity and sensitivity associated with manual microscopy diagnostics in operational conditions. These drawbacks constitute a major limiting factor to effective monitoring and preservation of vital anti-malarial medicines. Advances in digital microscopy performance and affordability have now opened the door to potentially significant improvements in the performance of malaria microscopy, overcoming serious deficiencies in current drug efficacy assessment, and more broadly in malaria diagnosis and management. Global Good (GG)/Intellectual Ventures Laboratory (IVL) sponsored by the Global Good Fund, has developed a microscope prototype consisting of low cost components to scan and capture images from Giemsa-stained thick blood films on slides. The captured images are analyzed with custom image analysis software developed at GG/IVL, using algorithms that are designed for automatic malaria diagnosis, without user input. Versions of a prototype of the device were first tested in field settings in Thailand in 2014-2015 at clinics operated by the Shoklo Malaria Research Unit (SMRU) and then again in 2016-2017. When compared to expert microscopy at SMRU, the performance of the device with respect to diagnostic sensitivity (87.8%), species identification (85.6% species correctly identified) and parasite density estimation (44% of estimates within +/-25% of reference microscopy result) corresponded to WHO Competence Level 2. The device and the accompanying image analysis algorithms have since been further developed and a new, third version of the prototype is now available for testing in diverse settings with varying malaria prevalence and user expertise.
Field Efficacy Of Insecticide Treated Uniforms And Skin Repellents for Malaria Prevention
MalariaPurpose While there is strong evidence that permethrin treated clothing prevents insect bites there is insufficient evidence from trials to demonstrate a reduction in infections. The evidence that topical insect repellants prevent malaria is more robust, but studies in civilian suffer from poor compliance. It is not known if there is an added benefit from combining the two. The effectiveness of permethrin-treated uniforms with and without DEET lotion are compared in a 2x2 design in Mgambo Jeshi la Kujenga Taifa (JKT) military camp in Tanga region. The four arms are: 1) combined intervention group receiving permethrin treated uniform (PTU) and 30% DEET (diethyl toluamide) liposome formula; 2) permethrin intervention group receiving PTU and placebo lotion; 3) DEET intervention group receiving untreated army combat uniform (ACU) and 30% DEET liposome formula; 4) placebo group receiving untreated ACU and placebo lotion. Both participants and investigators will be blinded to treatment allocation. The outcome measure is the incidence of Plasmodium falciparum malaria infection measured by Polymerase Chain Reaction every month by active case detection.
Evaluation of Seasonal Malaria Chemoprevention in Kita
MalariaAnemiaSeasonal malaria chemoprevention (SMC) is a new strategy recommended by World Health Organization in 2012 for areas of highly seasonal transmission such as the Sahel. Although randomized controlled trials have shown SMC to be highly effective, evidence and experience from routine implementation of SMC has been lacking. For these reasons, we conducted a comprehensive evaluation of the coverage, adherence, and impact of SMC on malaria infection and disease and anemia when delivered through routine programs using existing community health workers in the Kayes region in Mali. Our evaluation used a pre-post design with cross-sectional surveys and abstraction of routine health information system data in an intervention district (Kita) where SMC was implemented through the health system, and a comparison district (Bafoulabe) where SMC was not implemented.
Monitoring of Perfusion in Sepsis and Malaria
Severe SepsisMalariaSepsis and severe malaria together contribute to an estimated 13 million deaths annually, a great burden of which is in low-income countries. Optimal fluid management is critical yet remains one of the most challenging clinical care elements as volume overload precipitates pulmonary edema and volume restriction may exacerbate acute kidney injury. These complications of sepsis and severe malaria significantly increase mortality, particularly in resource-limited settings lacking mechanical ventilation and renal replacement therapy. Point-of-care ultrasound and passive leg raise testing are two easily implementable, safe and non-invasive clinical bedside fluid assessment tools that could be applied towards developing a fluid management algorithm in low resource settings. Similarly, simple tissue perfusion measures can facilitate understanding of precise indications or contraindication to fluid and vasopressor therapy. However, the performance of these tools has yet to be confirmed in these settings. Accurate assessment of pulmonary tolerance and fluid responsive patients could aid to tailor vasopressor and fluid therapy to the patient condition and disease phase, thus preventing or detecting iatrogenic pulmonary edema and other pulmonary complications. As there is currently limited evidence supporting fluid management recommendations for severe malaria and sepsis in low-resource settings, the potential application of these management tools could optimize supportive therapy and improve outcomes in these populations. The main activity proposed is a prospective, observational study of patients with sepsis and severe malaria to describe the relationship between fluid therapy and vasopressor therapy against measures of tissue perfusion and pulmonary congestion in adult patients with severe malaria or severe sepsis. In addition, the study will assess the performance of simple bedside clinical tools assessing fluid responsiveness, pulmonary congestion and peripheral tissue perfusion. The data from this observational study will facilitate the preparation of a follow-up study to test a clinical algorithm to guide individualized fluid and vasopressor administration.
Prevalence Survey of Antimalarial Drug Resistance Markers
MalariaStudy is cross-sectional and observational with one-time dried-blood spot sample collection from persons with laboratory-confirmed uncomplicated Plasmodium falciparum malaria (mixed or monoinfection). Samples will be analysed for the presence of molecular markers of resistance to ACT partner drugs (gene amplifications and/or other mutations in pfmdr1, gene amplifications of pfpm2, and additional mutations which may be identified during the course of the trial) in the first instance. Testing to detect additional markers of antimalarial drug resistance will also be performed where feasible. Prevalence of mutations will be summarized and mapped to provide intelligence on antimalarial drug resistance in the region of interest.
Cohort Event Monitoring in Sub Saharan Africa
MalariaThis cohort event monitoring will document real-life safety experiences following the intake of Injectable AS. Specifically, the study will record common adverse events that are associated with the use of Inj. AS and associating factors such as age and gender that make some of these events more likely. The sample size of 3000 patients will enable the documentation of causally-related events that occur at frequencies of 1 in 1000 or more. Since quinine, the previous gold standard for treating severe malaria may still be used by facilities in addition to artesunate and artemether, the study will concurrently monitor the safety of these products though focus of the study is the capture of adverse events following exposure to Inj. AS. The concurrent monitoring of both quinine and artemether will also enable treatment practices in the study areas to be documented.
Evaluation of a New Malaria Control Strategy Amongst Gold Miners Working Illegally in French Guiana...
MalariaPublic HealthIllegal gold miners in French Guiana, a French overseas territory ('département') located in Amazonia, often carry malaria parasites (up to 46.8%). While the Guiana Shield Region aims at malaria elimination, the high prevalence of Plasmodiumin this hard-to-reach population in conjunction with frequent incorrect use of artemisinin-based anti-malarials could favor the emergence of resistant parasites. Due to geographical and regulatory issues in French Guiana, usual malaria control strategies cannot be implemented in this particular context.Therefore, new strategies targeting this specific population in the forest are required. Numerous discussions among health institutions and scientific partners from French Guiana, Brazil and Suriname have led to an innovative project based on the distribution of kits for self-diagnosis and self-treatment of Plasmodium infections. The kit-distribution will be implemented at "resting sites", which are areas across the border of French Guiana regularly frequented by gold miners. The main objective is to increase the appropriate use and complete malaria treatment after a positive malaria diagnosis with a rapid test, which will be evaluated with before-and-after cross-sectional studies. Monitoring indicators will be collected from health mediators at the time of kit distribution and during subsequent visits, and from illegal gold miners themselves, through a smartphone application. The project funding is multisource, including Ministries of Health of the three countries, WHO/PAHO, and the European Union.
Feasibility, Acceptability and Costs of a Multiple First-lines Artemisinin-based Combination Therapies...
MalariaA simultaneous deployment of multiple first line therapies (MFT) for uncomplicated malaria using artemisisin based combination therapies as showed by theoretical models, may extend the useful therapeutic life of the current Artemisinin-based combination thérapies (ACTs) by reducing drug pressure and slowing the spread of resistance without putting life at risk. We therefore hypothesized that a simultaneous deployment of three ACTs targeting three segments of the population is feasible, acceptable and can achieve high coverage rate if potential barriers are well identified, well addressed and the key implementers are well-trained and adequately supported. To test this hypothesis, a quasi-experimental study will be conducted.
Estimating the Malaria Prevention Impact of New Nets: Observational Analyses to Evaluate the Evidence...
MalariaThe use of insecticide-treated bed nets (ITNs) has contributed to the substantial reduction in malaria cases and deaths. This progress is threatened by increasing resistance to commonly used insecticides in important mosquito vector populations. Newly developed, next-generation ITNs that use two insecticides, or an insecticide synergist and an insecticide, are effective at killing resistant mosquitoes, but large-scale uptake of these nets has been slow due to higher costs and lack of enough evidence to support broad policy recommendations. This observational study will occur alongside a pilot distribution of next-generation ITNs in two regions of Mozambique. Over three years, data on the entomological and epidemiological impact of the different ITN types will be collected. Data collection will occur in six districts: two districts receiving the dual-active ingredient ITN Interceptor® G2 (BASF: alphacypermethrin + chlorfenapyr); one district that will receive the dual-active ingredient ITN Royal Guard® (Disease Control Technologies: alphacypermethrin + pyriproxyfen); one district receiving an ITN containing an insecticide plus an insecticide synergist , Olyset®Plus (Sumitomo Chemical: permethrin + piperonyl butoxide); and two districts receiving the standard pyrethroid-only ITNs DuraNet® (Shobikaa Impex Private Limited: alphacypermethrin). Data will be collected on malaria vector bionomics, disease epidemiology, and ITN use in order to help better demonstrate the public health value of next-generation ITNs and to support donors, policymakers, and National Malaria Control Programs in their ITN decision-making and planning processes.
Antenatal Care as a Platform for Malaria Surveillance: Utilizing Community Prevalence Measures From...
MalariaThis study outlines a plan for conducting a routine assessment of malaria infection prevalence and intervention coverage using antenatal care (ANC) attendees. This will be a non-randomized assessment of the potential to use pregnant women attending their first ANC visit as a pragmatic sentinel population to monitor prevalence of malaria and the coverage of malaria control interventions. The use of a questionnaire, to include standard malaria rapid diagnostic testing, will be piloted with consenting women attending their first ANC visit at 21 individual health facilities across three of the New Net Project pilot study districts in western Mozambique: seven facilities each from Changara, Chemba, and Guro Districts. The results of the ANC questionnaires will be analyzed to see how well they correlate to similar malaria prevalence and intervention coverage estimates obtained during the contemporary community-based cross-sectional surveys administered during New Net Project pilot evaluation activities. As part of the New Nets Project, Mozambique is deploying next-generation ITNs through mass campaigns in pre-determined provinces. The present study aims to leverage planned New Nets Project cross-sectional surveys and strengthened routine case surveillance data in three of the study districts (Changara, Guro, and Chemba) to assess (1) whether the malaria infection prevalence data collected during ANC surveillance correlates with the cross-sectional survey estimates of community infection prevalence in children 6 to 59 months and (2) if intervention coverage data (particularly ITN ownership and use) collected from ANC surveillance are valid and representative of the population as a whole. These additional data could catalyze a new model of surveillance for malaria, and greatly simplify evaluation of the impact of new interventions, as ANC surveillance could potentially replace or supplement cross-sectional household surveys and provide more granular and timely data. All pregnant women attending first ANC visit at seven health facilities in each study district will be eligible for enrollment. Potential participants will be approached during their visit by a health facility worker. During group counselling sessions at initial intake, women will be informed of this pilot surveillance activity, and written informed consent will be obtained from each woman individually prior to routine ANC testing. All consenting women attending ANC first visit at a participating health facility will be tested for malaria using an RDT and asked to complete a study questionnaire which will include questions about the participant's net use, and care seeking behavior. It is expected to take 15 minutes to complete. Women who test positive for malaria will be given treatment according to national guidelines. There is no additional benefit to individual participants.