Journal Gates Open Research-
Gates Open Research; doi:10.12688/gatesopenres
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13049.1
Abstract:On-site sanitation facilities contribute to the majority of toilet facilities in developing countries as full waterborne sanitation is not feasible or affordable. The characteristics of faecal sludge vary greatly between different locations and types of onsite sanitation facilities and at the same time their understanding is crucial for improvement of the existing faecal sludge management services. The Pollution Research Group (PRG), within the School of Chemical Engineering in the University of Kwa-Zulu Natal have been focussing on the analysis of faecal sludge from different on-site sanitation, such as urine diversion and dehydration toilets, wet and dry ventilated improved pit latrines at household and community levels and unimproved pit latrines. This study was undertaken between 2012 and 2014 and focussed on the characteristics of faecal sludge obtained from different on-site sanitation facilities in the Durban metro area in South Africa. Sampling methods were developed and applied for different depth levels of the pits for each on-site sanitation facility. The analysis followed the PRG standard operation procedures for properties such as: moisture content, total solids, ash content, pH, chemical oxygen demand, density, nutrient contents and thermal properties.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13078.1
Abstract:The World Health Organization is currently developing 2030 goals for neglected tropical diseases (NTDs). In these, yaws has been targeted for eradication by 2030, with 50% of member states certified free of yaws transmission by 2023. Here we summarise the yaws modelling literature and discuss the proposed goal and strategy. The current Morges strategy involves rounds of Total Community Treatment (TCT), in which all members of the community are treated, and Total Targeted Treatment (TTT), treating active cases and their contacts. However, modelling and empirical work suggest that latent infections are often not found in the same household as active cases, reducing the utility of household-based contact tracing for a TTT strategy. Economic modelling has also discovered uncertainty in the cost of eradication, requiring further data to give greater information. We also note the need for improved active surveillance in previously endemic countries, in order to plan future intervention efforts and ensure global eradication.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.12963.2
Abstract:Background: Neonatal infection is the third largest cause of death in children under five worldwide. Nutritional immunity is the process by which the host innate immune system limits nutrient availability to invading organisms. Iron is an essential micronutrient for both microbial pathogens and their mammalian hosts. Changes in iron availability and distribution have significant effects on pathogen virulence and on the immune response to infection. Our previously published data shows that, during the first 24 hours of life, full-term neonates have reduced overall serum iron. Transferrin saturation decreases rapidly from 45% in cord blood to ~20% by six hours post-delivery. Methods: To study neonatal nutritional immunity and its role in neonatal susceptibility to infection, we will conduct an observational study on 300 full-term normal birth weight (FTB+NBW), 50 preterm normal birth weight (PTB+NBW), 50 preterm low birth weight (PTB+LBW) and 50 full-term low birth weight (FTB+LBW), vaginally-delivered neonates born at Kanifing General Hospital, The Gambia. We will characterize and quantify iron-related nutritional immunity during the early neonatal period and use ex vivo sentinel bacterial growth assays to assess how differences in serum iron affect bacterial growth. Blood samples will be collected from the umbilical cord (arterial and venous) and at serial time points from the neonates over the first week of life. Discussion: Currently, little is known about nutritional immunity in neonates. In this study, we will increase understanding of how nutritional immunity may protect neonates from infection during the first critical days of life by limiting the pathogenicity and virulence of neonatal sepsis causing organisms by reducing the availability of iron. Additionally, we will investigate the hypothesis that this protective mechanism may not be activated in preterm and low birth weight neonates, potentially putting these babies at an enhanced risk of neonatal infection. Trial registration: clinicaltrials.gov (NCT03353051) 27/11/2017
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.12970.1
Abstract:Background: Adolescents 360 (A360) implements the Smart Start (SS) programme through Ethiopia’s Health Extension Programme (HEP). SS is premised on financial planning as an entry point to discuss family planning (FP) with newly married couples and central to its delivery are the health extension workers (HEW). This article evaluates the A360 experience and learning from the process evaluation implemented by Itad to understand contextual barriers and enablers from the perspective of the HEW. Methods: A purposive sampling strategy was employed whereby 27 key stakeholders were identified from Oromia, Addis Ababa and Amhara, based on exposure to the SS programme. Findings from the action research were shared with A360 through a one day sounding workshop. Results: Findings revealed that many local government and communal respondents do not view adolescent pregnancy as a problem, unless out of wedlock, and adolescent pregnancy is closely linked to early marriage. As a result, some providers, including HEWs, acknowledged that married adolescent girls were previously ‘neglected’ by them, while husbands indicated that they had not previously been included in FP counselling. Findings also revealed some challenges with SS implementation as HEWs were ‘deprioritizing’ the intervention and many HEWs had been in situ for several years and were overworked and frustrated. Against this backdrop, A360 was viewed as adding to the HEW workload. While the programme design was focused on adolescent users, there was increasing recognition that HEWs also needed to be at the centre of solution design. Conclusions: Despite challenges associated with the HEP, Ethiopia FP2020 plans to support the ‘next generation’ of HEWs, including a focus on adolescents and youth. To gain deeper insight and put the HEW at the centre of design, A360 will continue to work with the process evaluation to understand contextual barriers and enablers from the perspective of the HEW.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.12895.2
Abstract:This study investigated the phenotypic variation of continuous storage root formation and bulking (CSRFAB) growth patterns underlying the development of sweetpotato genotypes for identification of potential varieties adapted to piecemeal harvesting for small scale farmers. The research was conducted between September 2016 and August 2017 in Uganda. Genotypes from two distinct sweetpotato genepool populations (Population Uganda A and Population Uganda B) comprising 130 genotypes, previously separated using 31 simple sequence repeat (SSR) markers were used. Measurements (4 harvest times with 4 plants each) were repeated on genotypes in a randomized complete block design with 2 replications in 2 locations for 2 seasons. We developed a scoring scale of 1 to 9 and used it to compare growth changes between consecutive harvests. Data analysis was done using residual or restricted maximum likelihood (REML) in GenStat 18th Edition. There were strong linear and quadratic trends over time (P
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13074.1
Abstract:Dog-mediated rabies continues to kill tens of thousands of people every year in low- and middle-income countries despite being an entirely vaccine-preventable disease. WHO and partners have launched a global campaign to reach zero human deaths from dog-mediated rabies by 2030. The primary tools for reaching this target are mass dog vaccination to control and interrupt transmission in domestic dog populations that maintain infection, and appropriate post-exposure prophylaxis (PEP) for rabies-exposed persons to prevent the fatal onset of disease. Models have been developed to assess the feasibility, impact and cost-effectiveness of these measures. From these models, we argue that the 2030 target of zero human rabies deaths is achievable, but will require concerted effort, engagement and investment. A proposed Gavi investment in human rabies vaccines has potential to drive progress towards the 2030 target; however, concomitant investment is needed to scale up mass dog vaccination or this target will be missed. Predicted economic benefits of mass dog vaccination vary according to national PEP provisioning and access to care. Integrated Bite Case Management can enhance surveillance and rationalize PEP use, but needs adapting to and integrating within local health systems and international reporting systems to improve PEP accountability, monitor impacts and support verification of disease freedom. Modelling is required for projecting more realistic and geographically specific timelines for achieving targets, in line with the implementation of interventions. The greatest risk to the ‘Zero by 30’ strategy is the limited long-term cross-sectoral or targeted financing to support countries to deliver and sustain mass dog vaccination.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13070.1
Abstract:Gambiense human African trypanosomiasis (gHAT) is a parasitic, vector-borne neglected tropical disease that has historically affected populations across West and Central Africa and can result in death if untreated. Following from the success of recent intervention programmes against gHAT, the World Health Organization (WHO) has defined a 2030 goal of global elimination of transmission (EOT). The key proposed indicator to measure achievement of the goal is to have zero reported cases. Results of previous mathematical modelling and quantitative analyses are brought together to explore both the implications of the proposed indicator and the feasibility of achieving the WHO goal. Whilst the indicator of zero case reporting is clear and measurable, it is an imperfect proxy for EOT and could arise either before or after EOT is achieved. Lagging reporting of infection and imperfect diagnostic specificity could result in case reporting after EOT, whereas the converse could be true due to underreporting, lack of coverage, and cryptic human and animal reservoirs. At the village-scale, the WHO recommendation of continuing active screening until there are three years of zero cases yields a high probability of local EOT, but extrapolating this result to larger spatial scales is complex. Predictive modelling of gHAT has consistently found that EOT by 2030 is unlikely across key endemic regions if current medical-only strategies are not bolstered by improved coverage, reduced time to detection and/or complementary vector control. Unfortunately, projected costs for strategies expected to meet EOT are high in the short term and strategies that are cost-effective in reducing burden are unlikely to result in EOT by 2030. Future modelling work should aim to provide predictions while taking into account uncertainties in stochastic dynamics and infection reservoirs, as well as assessment of multiple spatial scales, reactive strategies, and measurable proxies of EOT.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13053.1
Abstract:Background: Group antenatal care has demonstrated promise as a service delivery model that may result in improved outcomes compared to standard antenatal care in socio-demographic populations at disparately high risk for poor perinatal outcomes. Intrigued by results from the United States showing lower preterm birth rates among high-risk women who participate in group antenatal care, partners working together as the Preterm Birth Initiative - Rwanda designed a trial to assess the impact of group antenatal care on gestational age at birth. Methods: This study is a pair-matched cluster randomized controlled trial with four arms. Pairs randomized to group or standard care were further matched with other pairs into quadruples, within which one pair was assigned to implement basic obstetric ultrasound at the health center and early pregnancy testing at the community. At facilities randomized to group care, this will follow the opt-out model of service delivery and individual visits will always be available for those who need or prefer them. The primary outcome of interest is mean gestational age at birth among women who presented for antenatal care before 24 completed weeks of pregnancy and attended more than one antenatal care visit. Secondary outcomes of interest include attendance at antenatal and postnatal care, preterm birth rates, satisfaction of mothers and providers, and feasibility. A convenience sample of women will be recruited to participate in a longitudinal survey in which they will report such indicators as self-reported health-related behaviors and depressive symptoms. Providers will be surveyed about satisfaction and stress. Discussion: This is the largest cluster randomized controlled trial of group antenatal and postnatal care ever conducted, and the first in a low- or middle-income country to examine the effect of this model on gestational age at birth. Trial registration: This study is registered on ClinicalTrials.gov as NCT03154177 May 16, 2017.
Gates Open Research, Volume 3; doi:10.12688/gatesopenres.13068.1
Abstract:Taenia solium (TS), responsible for porcine cysticercosis, human taeniasis and (neuro)cysticercosis, was included in the World Health Organization neglected tropical disease (NTD) roadmap published in 2012. Targets set in this roadmap have not been met, but T. solium has been included in the consultation process for the new 2030 goals proposed for priority NTDs. Taenia solium transmission dynamics models can contribute to this process. A recent review has compared existing T. solium transmission models, identifying their similarities and differences in structure, parameterization and modelled intervention approaches. While a formal model comparison to investigate the impact of interventions is yet to be conducted, the models agree on the importance of coverage for intervention effectiveness and on the fact that human- and pig-focused interventions can be optimally combined. One of these models, cystiSim, an individual-based, stochastic model has been used to assess field-applicable interventions, some currently under evaluation in on-going trials in Zambia. The EPICYST, population-based, deterministic model has highlighted, based on simulating a generic sub-Saharan Africa setting, the higher efficacy (measured as the percentage of human cysticercosis cases prevented) of biomedical interventions (human and pig treatment and pig vaccination) compared to improved husbandry, sanitation, and meat inspection. Important questions remain regarding which strategies and combinations thereof provide sustainable solutions for severely resource-constrained endemic settings. Defining realistic timeframes to achieve feasible targets, and establishing suitable measures of effectiveness for these targets that can be quantified with current monitoring and evaluation tools, are current major barriers to identifying validated strategies. Taenia solium transmission models can support setting achievable 2030 goals; however, the refinement of these models is first required. Incorporating socio-economic elements, improved understanding of underlying biological processes, and consideration of spatial dynamics are key knowledge gaps that need addressing to support model development.