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Item Water security in South Africa: perceptions on public expectations and municipal obligations, governance and water re-use(Creative Commons Attribution Licence, 2016-07-03) Sershen, S.; Rodda, N.; Stenström, Thor-Axel; Schmidt, S.; Dent, M.; Bux, Faizal; Hanke, N.; Buckley, C. A.; Fennemore, C.South Africa is a water-scarce country with increasing pressure on its water resources. Urgent interventions are needed to protect water security within this rapidly developing country. This paper reports on an interdisciplinary Water Security Colloquium, convened by the South African Young Academy of Science in 2014. A selected group of water professionals from academia, civil society and local government was brought together to discuss water security under three focus themes: ‘public expectations and municipal obligations’, ‘water security and governance: challenges and advances’, and ‘water re-use: health and infrastructural considerations’. Participant perceptions were generated using a focus group methodology, combined with participatory data collection methods. Under each theme, inputs were categorised as ‘challenges’, ‘gaps in knowledge’, and ‘solutions/recommendations’ and these inputs were thereafter ranked in order of importance via a ‘voting’ process. Major challenges perceived included a lack of both skills and political will in government, a need to restore citizen trust in government intention and capability to deliver water-related services, and a failure to up-scale existing water re-use technology. Participants identified understanding of the process and implications of the Green and Blue Drop Programmes, knowledge transfer to the public, and the role of educators as major knowledge gaps. The top suggestions proposed included creating public awareness around and buy-in to initiatives to improve water security, accessible and user-friendly conversion of research results to implementation, and ensuring an active role for educators in creating awareness around water security. In view of the concerns identified, participants suggested as potential solutions: improving government and public understanding around water issues, incentivising water re-use and conservation, introducing rising block tariffs and improving human capacity development in the water sector. Developing the ecological infrastructure that protects both quantity and quality of water and building strong partnerships among all stakeholders were also recognised as key.Item Antibiogram of environmental isolates of Acinetobacter calcoaceticus from Nkonkobe Municipality, South Africa(PSP, 2016) Stenström, Thor-Axel; Okoh, Anthony I.; Adegoke, Anthony AyodejiThe antibiogram of Acinetobacter isolates from freshwater and soil samples in Alice and Fort Beaufort towns in Nkonkobe Municipality, South Africa were assessed for their extended beta-lactamase (ESBL) spectrum. Eighty-six Acinetobacter isolates were obtained from the 50 samples of soil and 50 samples of water (25 in each location) analysed. The resistance of the Acinetobacter isolates ranged between 30-100% against penicillin G, ceftriazone, nitrofurantoin, erythromycin and augmentin, while 9% showed intermediate response to minocycline, and 10% were resistant to oxytetracycline. Both Tet B and Tet 39 were detected in 66.7 % of the tetracycline resistant Acinetobacter isolates and in 44.4 % of the intermediately tetracycline resistant Acinetobacter isolates. An observation of 9.3% phenotypic expression of ESBLs was made while 3.5% were carrying the blaCTX-M-1 gene; all of which were susceptible to the fluoroquinolone. The multiple antibiotic resistance (MAR) index of > 0.2 indicates that the isolates emerged from high-risk sources, in line with conventional standards. Commensal Acinetobacter spp in the environment have proven to be one of reservoirs for antibiotic resistance genes.Item Exploring the potential reservoirs of non specific TEM beta lactamase (blaTEM) gene in the Indo-Gangetic region : a risk assessment approach to predict health hazards(Elsevier, 2016) Singh, Gulshan; Vajpayee, Poornima; Rani, Neetika; Amoah, Isaac Dennis; Stenström, Thor-Axel; Shanker, RishiThe emergence of antimicrobial resistant bacteria is an important public health and environ-mental contamination issue. Antimicrobials of -lactam group accounts for approximately two thirds, by weight, of all antimicrobials administered to humans due to high clinical efficacy and low toxicity. This study explores -lactam resistance determinant gene (blaTEM) as emerging con-taminant in Indo-Gangetic region using qPCR in molecular beacon format. Quantitative Microbial Risk Assessment (QMRA) approach was adopted to predict risk to human health associated with consumption/exposure of surface water, potable water and street foods contaminated with bac-teria having blaTEM gene. It was observed that surface water and sediments of the river Ganga and Gomti showed high numbers of blaTEM gene copies and varied significantly (p < 0.05) among the sampling locations. The potable water collected from drinking water facility and clinical set-tings exhibit significant number of blaTEM gene copies (13 ± 0.44–10200 ± 316 gene copies/100 mL).Item A cluster-randomized controlled trial to reduce Diarrheal disease and dengue entomological risk factors in rural primary schools in Colombia(National Centre for Biotechnology Information, 2016-11-07) Overgaard, Hans J.; Alexander, Neal; Matiz, María Inés; Jaramillo, Juan Felipe; Olano, Victor Alberto; Vargas, Sandra Lucía; Sarmiento, Diana; Lenhart, Audrey; Stenström, Thor-AxelBackground As many neglected tropical diseases are co-endemic and have common risk factors, inte-grated control can efficiently reduce disease burden and relieve resource-strained public health budgets. Diarrheal diseases and dengue fever are major global health problems sharing common risk factors in water storage containers. Where provision of clean water is inadequate, water storage is crucial. Fecal contamination of stored water is a common source of diarrheal illness, but stored water also provides breeding sites for dengue vector mosquitoes. Integrating improved water management and educational strategies for both diseases in the school environment can potentially improve the health situation for students and the larger community. The objective of this trial was to investigate whether interven-tions targeting diarrhea and dengue risk factors would significantly reduce absence due to diarrheal disease and dengue entomological risk factors in schools. Methodology/Principal Findings A factorial cluster randomized controlled trial was carried out in 34 rural primary schools (1,301 pupils) in La Mesa and Anapoima municipalities, Cundinamarca, Colombia. Schools were randomized to one of four study arms: diarrhea interventions (DIA), dengue interven-tions (DEN), combined diarrhea and dengue interventions (DIADEN), and control (CON). Interventions had no apparent effect on pupil school absence due to diarrheal disease (p = 0.45) or on adult female Aedes aegypti density (p = 0.32) (primary outcomes). However, the dengue interventions reduced the Breteau Index on average by 78% (p = 0.029), with Breteau indices of 10.8 and 6.2 in the DEN and DIADEN arms, respectively compared to 37.5 and 46.9 in the DIA and CON arms, respectively. The diarrhea interventions improved water quality as assessed by the amount of Escherichia coli colony forming units (CFU); the ratio of Williams mean E. coli CFU being 0.22, or 78% reduction (p = 0.008). Conclusions/Significance Integrated control of dengue and diarrhea has never been conducted before. This trial pres-ents an example for application of control strategies that may affect both diseases and the first study to apply such an approach in school settings. The interventions were well received and highly appreciated by students and teachers. An apparent absence of effect in primary outcome indicators could be the result of pupils being exposed to risk factors out-side the school area and mosquitoes flying in from nearby uncontrolled breeding sites. Inte-grated interventions targeting these diseases in a school context remain promising because of the reduced mosquito breeding and improved water quality, as well as educa-tional benefits. However, to improve outcomes in future integrated approaches, simulta-neous interventions in communities, in addition to schools, should be considered; using appropriate combinations of site-specific, effective, acceptable, and affordable interventions.Item Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia(Instituto Oswaldo Cruz, Ministério da Saúde, 2016-04) Pérez-Castro, Rosalía; Castellanos, Jaime E.; Olano, Victor Alberto; Matiz, María Inés; Jaramillo, Juan Felipe; Vargas, Sandra Lucía; Sarmiento, Diana; Stenström, Thor-Axel; Overgaard, Hans J.The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The in-formation about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus res-ervoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.Item Quantification of pathogen inactivation efficacy by free chlorine disinfection of drinking water for QMRA(IWA Publishing, 2015-09-13) Petterson, S.R.; Stenström, Thor-AxelTo support the implementation of quantitative microbial risk assessment (QMRA) for managing infectious risks associated with drinking water systems, a simple modeling approach for quantifying Log10 reduction across a free chlorine disinfection contactor was developed. The study was undertaken in three stages: firstly, review of the laboratory studies published in the literature; secondly, development of a conceptual approach to apply the laboratory studies to full-scale conditions; and finally implementation of the calculations for a hypothetical case study system. The developed model explicitly accounted for variability in residence time and pathogen specific chlorine sensitivity. Survival functions were constructed for a range of pathogens relying on the upper bound of the reported data transformed to a common metric. The application of the model within a hypothetical case study demonstrated the importance of accounting for variable residence time in QMRA. While the overall Log10 reduction may appear high, small parcels of water with short residence time can compromise the overall performance of the barrier. While theoretically simple, the approach presented is of great value for undertaking an initial assessment of a full-scale disinfection contactor based on limited site-specific information.Item Schools as potential risk sites for Vector-Borne disease transmission: mosquito vectors in rural schools in two municipalities in Colombia(The American Mosquito Control Association, Inc., 2015) Olano, Victor Alberto; Matiz, María Inés; Lenhart, Audrey; Cabezas, Laura; Vargas, Sandra Lucía; Jaramillo, Juan Felipe; Sarmiento, Diana; Alexander, Neil; Stenström, Thor-Axel; Overgaard, Hans J.Dengue and other vector-borne diseases are of great public health importance in Colombia. Vector surveillance and control activities are often focused at the household level. Little is known about the importance of nonhousehold sites, including schools, in maintaining vector-borne disease transmission. The objectives of this paper were to determine the mosquito species composition in rural schools in 2 municipalities in Colombia and to assess the potential risk of vector-borne disease transmission in school settings. Entomological surveys were carried out in rural schools during the dry and rainy seasons of 2011. A total of 12 mosquito species were found: Aedes aegypti, Anopheles pseudopunctipennis, Culex coronator, Cx. quinquefasciatus, and Limatus durhamii in both immature and adult forms; Ae. fluviatilis, Cx. nigripalpus, Cx. corniger, and Psorophora ferox in immature forms only; and Ae. angustivittatus, Haemagogus equinus, and Trichoprosopon lampropus in adult forms only. The most common mosquito species was Cx. quinquefasciatus. Classrooms contained the greatest abundance of adult female Ae. aegypti and Cx. quinquefasciatus. The most common Ae. aegypti breeding sites were containers classified as “others” (e.g., cans), followed by containers used for water storage. A high level of Ae. aegypti infestation was found during the wet season. Our results suggest that rural schools are potentially important foci for the transmission of dengue and other mosquito-borne diseases. We propose that public health programs should be implemented in rural schools to prevent vector-borne diseases.Item Strategies for building resilience to hazards in water, sanitation and hygiene (WASH) systems: The role of public private partnerships(Elsevier, 2014-07-15) Johannessen, Ase; Rosemarin, Arno; Thomalla, Frank; Gerger Swartling, Åsa; Stenström, Thor-Axel; Vulturius, GregorThe aim of this paper is to enhance understanding of how the resilience of water, sanitation and hygiene (WASH) systems to hazards can be improved. In turn, this aims to inform different strategies for public and private partnerships (PPPs). In a new approach, to acknowledge the multi levelled nature of resilience; risk at the relevant levels are taken into account, (regional/river basin, urban area, and individual). For these levels, we first describe the different components of risk, vulnerability and resilience of the WASH system that influence people's exposure to hazards. We illustrate these components using examples from case studies in the literature. Using a social learning lens - a crucial ingredient of resilience - we examine opportunities for reducing risks through improving public–private engagement. These are presented as strategies which could guide invest-ment decisions: As pressures from climate change and development add up, businesses must become aware of the risks involved in operating and investing without considering ecosystem health, both in terms of the services they provide for mitigating floods and droughts, as well as in terms of the development approaches that define how ecosystems are managed (e.g. “making space” for, rather than controlling water). There is a need to develop an institutional culture that strives towards greener and more resilient urban environments with the help of various quality assurance methods. Partnerships must reach the poorer customer base, encourage informal small entrepreneurs, and boost financial mechanisms (e.g. micro-insurance, micro-finance) to support the most vulner-able in society.