Ricardo J Soares Magalhaes | The University of Queensland, Australia (original) (raw)
Papers by Ricardo J Soares Magalhaes
PLOS Neglected Tropical Diseases, 2015
In order to increase the efficient allocation of soil-transmitted helminth (STH) disease control ... more In order to increase the efficient allocation of soil-transmitted helminth (STH) disease control resources in the Philippines, we aimed to describe for the first time the spatial variation in the prevalence of A. lumbricoides, T. trichiura and hookworm across the country, quantify the association between the physical environment and spatial variation of STH infection and develop predictive risk maps for each infection. Data on STH infection from 35,573 individuals across the country were geolocated at the barangay level and included in the analysis. The analysis was stratified geographically in two major regions: 1) Luzon and the Visayas and 2) Mindanao. Bayesian geostatistical models of STH prevalence were developed, including age and sex of individuals and environmental variables (rainfall, land surface temperature and distance to inland water bodies) as predictors, and diagnostic uncertainty was incorporated. The role of environmental variables was different between regions of the Philippines. This analysis revealed that while A. lumbricoides and T. trichiura infections were widespread and highly endemic, hookworm infections were more circumscribed to smaller foci in the Visayas and Mindanao. This analysis revealed significant spatial variation in STH infection prevalence within provinces of the Philippines. This suggests that a spatially targeted approach to STH interventions, including mass drug administration, is warranted. When financially possible, additional STH surveys should be prioritized to high-risk areas identified by our study in Luzon.
Advances in Parasitology, 2011
Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable map... more Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes.
Plos Medicine, 2011
Background: Childhood anaemia is considered a severe public health problem in most countries of s... more Background: Childhood anaemia is considered a severe public health problem in most countries of sub-Saharan Africa. We investigated the geographical distribution of prevalence of anaemia and mean haemoglobin concentration (Hb) in children aged 1-4 y (preschool children) in West Africa. The aim was to estimate the geographical risk profile of anaemia accounting for malnutrition, malaria, and helminth infections, the risk of anaemia attributable to these factors, and the number of anaemia cases in preschool children for 2011.
PloS one, 2013
Rabies is a significant public health problem in China in that it records the second highest case... more Rabies is a significant public health problem in China in that it records the second highest case incidence globally. Surveillance data on canine rabies in China is lacking and human rabies notifications can be a useful indicator of areas where animal and human rabies control could be integrated. Previous spatial epidemiological studies lacked adequate spatial resolution to inform targeted rabies control decisions. We aimed to describe the spatiotemporal distribution of human rabies and model its geographical spread to provide an evidence base to inform future integrated rabies control strategies in China. We geo-referenced a total of 17,760 human rabies cases of China from 2005 to 2011. In our spatial analyses we used Gaussian kernel density analysis, average nearest neighbor distance, Spatial Temporal Density-Based Spatial Clustering of Applications with Noise and developed a model of rabies spatiotemporal spread. Human rabies cases increased from 2005 to 2007 and decreased during...
Advances in Parasitology, 2011
Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable map... more Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes.
Preventive Veterinary Medicine, 2011
Over the past two decades, the poultry sector in China went through a phase of tremendous growth ... more Over the past two decades, the poultry sector in China went through a phase of tremendous growth as well as rapid intensification and concentration. Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 was first detected in 1996 in Guangdong province, South China and started spreading throughout Asia in early 2004. Since then, control of the disease in China has relied heavily on wide-scale preventive vaccination combined with movement control, quarantine and stamping out. This strategy has been successful in drastically reducing the number of outbreaks during the past 5 years. However, HPAIV H5N1 is still circulating and is regularly isolated in traditional live bird markets (LBMs) where viral infection can persist, which represent a public health hazard for people visiting them. The use of social network analysis in combination with epidemiological surveillance in South China has identified areas where the success of current strategies for HPAI control in the poultry production sector may benefit from better knowledge of poultry trading patterns and the LBM network configuration as well as their capacity for maintaining HPAIV H5N1 infection. We produced a set of LBM network maps and estimated the associated risk of HPAIV H5N1 within LBMs and along poultry market chains, providing new insights into how live poultry trade and infection are intertwined. More specifically, our study provides evidence that several biosecurity factors such as daily cage cleaning, daily cage disinfection or manure processing contribute to a reduction in HPAIV H5N1 presence in LBMs. Of significant importance is that the results of our study also show the association between social network indicators and the presence of HPAIV H5N1 in specific network configurations such as the one represented by the counties of origin of the birds traded in LBMs. This new information could be used to develop more targeted and effective control interventions.
PLoS ONE, 2012
Background: The number of outbreaks of highly pathogenic avian influenza virus of the H5N1 subtyp... more Background: The number of outbreaks of highly pathogenic avian influenza virus of the H5N1 subtype (HPAIV H5N1) over the past 5 years has been drastically reduced in China but sporadic infections in poultry and humans are still occurring. In this study, we aimed to investigate seasonal patterns in the association between the movement of live poultry originating from southern China and HPAIV H5N1 infection history in humans and poultry in China.
Bulletin of the World Health Organization, 2011
Vietnam and Thailand in late 2003, causing severe mortality in affected flocks. Given that the vi... more Vietnam and Thailand in late 2003, causing severe mortality in affected flocks. Given that the virus has crossed the species barrier between poultry and humans and caused human fatalities, national governments and international agencies are intensively studying measures to control the spread of the disease. Among these strategic options would be 'restructuring' the poultry industry in ways that could threaten the livelihoods of smallholder backyard producers.
Food and Agriculture …, 2007
Because of human and livestock population growth, changes in livestock production, the emergence ... more Because of human and livestock population growth, changes in livestock production, the emergence of worldwide agro-food networks, and significant changes in personal mobility, human populations increasingly share a global commons of disease risk, among themselves and with domestic and wild animal species. To elucidate the linkage between livestock production and global public health, this paper draws upon recent experiences provided by different influenza A virus (IAV) incursions into domestic livestock populations, the most notable one being the ongoing HPAI H5N1 epidemic that originated in Asia, which now also affects Africa and which has led to outbreaks in the Near East and in Europe.
Scientific reports, 2015
Following rapid, global clonal dominance of hypervirulent ribotypes, Clostridium difficile now co... more Following rapid, global clonal dominance of hypervirulent ribotypes, Clostridium difficile now constitutes the primary infectious cause of nosocomial diarrhoea. Evidence indicates at least three possible mechanisms of hypervirulence that facilitates the successful invasion of these atypical strains: 1) increased infectiousness relative to endemic strains; 2) increased symptomatic disease rate relative to endemic strains; and 3) an ability to outcompete endemic strains in the host's gut. Stochastic simulations of an infection transmission model demonstrate clear differences between the invasion potentials of C. difficile strains utilising the alternative hypervirulence mechanisms, and provide new evidence that favours certain mechanisms (1 and 2) more than others (3). Additionally, simulations illustrate that direct competition between strains (inside the host's gut) is not a prerequisite for the sudden switching that has been observed in prevailing ribotypes; previously domi...
PLoS Neglected Tropical Diseases
Background Mapping the distribution of schistosomiasis is essential to determine where control pr... more Background Mapping the distribution of schistosomiasis is essential to determine where control programs should operate, but because it is impractical to assess infection prevalence in every potentially endemic community, model-based geostatistics (MBG) is increasingly being used to predict prevalence and determine intervention strategies. Methodology/Principal Findings To assess the accuracy of MBG predictions for Schistosoma haematobium infection in Ghana, school surveys were evaluated at 79 sites to yield empiric prevalence values that could be compared with values derived from recently published MBG predictions. Based on these findings schools were categorized according to WHO guidelines so that practical implications of any differences could be determined. Using the mean predicted values alone, 21 of the 25 empirically determined ‘high-risk’ schools requiring yearly praziquantel would have been undertreated and almost 20% of the remaining schools would have been treated despite ...
Australian Journal of Rural Health, 2011
Complementary and alternative medicine (CAM) use is high in rural health and an agenda for resear... more Complementary and alternative medicine (CAM) use is high in rural health and an agenda for research in the geography of CAM has been outlined. Unfortunately, no studies to date have mapped the geographic distribution of CAM practitioners in rural areas. For the first time we investigate CAM practitioner distributions across a large district/region in rural Australia. A CAM infrastructure audit of practitioners was performed in rural Divisions of General Practice in New South Wales, Australia. CAM providers form a significant part of the health care system in rural New South Wales with substantial representation across all degrees of rurality and in both under-serviced and well-serviced areas. CAM practitioners outnumbered GPs in four NSW Divisions of General Practice and in no Division numbered less than half of the total number of GPs. Given the challenges of access to and recruitment and retention of conventional health care providers in rural settings and the significant presence of CAM practitioners, it is possible to consider such practitioners as an untapped resource in rural health care delivery. Assuming appropriate regulatory and quality standards are in place this resource should attract careful attention as part of future rural health policy and planning. The significant presence and high prevalence of use of CAM practitioners should also serve as an impetus to reform CAM service delivery in Australia.
Malaria Journal, 2012
Background: Identifying and targeting hyper-endemic communities within meso-endemic areas constit... more Background: Identifying and targeting hyper-endemic communities within meso-endemic areas constitutes an important challenge in malaria control in endemic countries such like Angola. Recent national and global predictive maps of malaria allow the identification and quantification of the population at risk of malaria infection in Angola, but their small-scale accuracy is surrounded by large uncertainties. To observe the need to develop higher resolution malaria endemicity maps a predictive risk map of malaria infection for the municipality of Dande (a malaria endemic area in Northern Angola) was developed and compared to existing national and global maps, the role of individual, household and environmental risk factors for malaria endemicity was quantified and the spatial variation in the number of children at-risk of malaria was estimated. Methods: Bayesian geostatistical models were developed to predict small-scale spatial variation using data collected during a parasitological survey conducted from May to August 2010. Maps of the posterior distributions of predicted prevalence were constructed in a geographical information system. Results: Malaria infection was significantly associated with maternal malaria awareness, households with canvas roofing, distance to health care centre and distance to rivers. The predictive map showed remarkable spatial heterogeneity in malaria risk across the Dande municipality in contrast to previous national and global spatial risk models; large high-risk areas of malaria infection (prevalence >50%) were found in the northern and most eastern areas of the municipality, in line with the observed prevalence.
Background and Objective: In Nepal, gastrointestinal helminthiases are endemic in indigenous peop... more Background and Objective: In Nepal, gastrointestinal helminthiases are endemic in indigenous people living in low laying areas of the country. However, little is known regarding the role of different socio-economic indicators on helminth infections in these communities. The main aim of this study is to identify the relationship between socio-economic factors and helminth infection in an indigenous community in Nepal.
PLoS ONE, 2012
Background: Malaria, schistosomiasis and geohelminth infection are linked to maternal and child m... more Background: Malaria, schistosomiasis and geohelminth infection are linked to maternal and child morbidity and mortality in sub-Saharan Africa. Knowing the prevalence levels of these infections is vital to guide governments towards the implementation of successful and cost-effective disease control initiatives.
EcoHealth, 2014
A recent study in Western Australia identified area level associations between soil salinisation ... more A recent study in Western Australia identified area level associations between soil salinisation and hospital admissions for depression. Our study assessed the quantitative relationship between mental health measures at the individual level and location specific environmental measurements on salinity, as well as two other indicators of environmental degradation and change: land surface temperature and normalised difference vegetation index, a proxy for rainfall. Location-specific environmental measurements were linked to individual mental health scores of women in three age cohorts from the Australian Longitudinal Study on Women's Health using a geographic information system. Bayesian geostatistical linear regression models were developed to assess associations between environmental exposures and mental health scores of women. In contrast to previous studies using area level measures, our study found no associations between individual level measurements of mental health scores for women in south-west Western Australia and salinity, LST or NDVI.
PLOS Neglected Tropical Diseases, 2015
In order to increase the efficient allocation of soil-transmitted helminth (STH) disease control ... more In order to increase the efficient allocation of soil-transmitted helminth (STH) disease control resources in the Philippines, we aimed to describe for the first time the spatial variation in the prevalence of A. lumbricoides, T. trichiura and hookworm across the country, quantify the association between the physical environment and spatial variation of STH infection and develop predictive risk maps for each infection. Data on STH infection from 35,573 individuals across the country were geolocated at the barangay level and included in the analysis. The analysis was stratified geographically in two major regions: 1) Luzon and the Visayas and 2) Mindanao. Bayesian geostatistical models of STH prevalence were developed, including age and sex of individuals and environmental variables (rainfall, land surface temperature and distance to inland water bodies) as predictors, and diagnostic uncertainty was incorporated. The role of environmental variables was different between regions of the Philippines. This analysis revealed that while A. lumbricoides and T. trichiura infections were widespread and highly endemic, hookworm infections were more circumscribed to smaller foci in the Visayas and Mindanao. This analysis revealed significant spatial variation in STH infection prevalence within provinces of the Philippines. This suggests that a spatially targeted approach to STH interventions, including mass drug administration, is warranted. When financially possible, additional STH surveys should be prioritized to high-risk areas identified by our study in Luzon.
Advances in Parasitology, 2011
Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable map... more Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes.
Plos Medicine, 2011
Background: Childhood anaemia is considered a severe public health problem in most countries of s... more Background: Childhood anaemia is considered a severe public health problem in most countries of sub-Saharan Africa. We investigated the geographical distribution of prevalence of anaemia and mean haemoglobin concentration (Hb) in children aged 1-4 y (preschool children) in West Africa. The aim was to estimate the geographical risk profile of anaemia accounting for malnutrition, malaria, and helminth infections, the risk of anaemia attributable to these factors, and the number of anaemia cases in preschool children for 2011.
PloS one, 2013
Rabies is a significant public health problem in China in that it records the second highest case... more Rabies is a significant public health problem in China in that it records the second highest case incidence globally. Surveillance data on canine rabies in China is lacking and human rabies notifications can be a useful indicator of areas where animal and human rabies control could be integrated. Previous spatial epidemiological studies lacked adequate spatial resolution to inform targeted rabies control decisions. We aimed to describe the spatiotemporal distribution of human rabies and model its geographical spread to provide an evidence base to inform future integrated rabies control strategies in China. We geo-referenced a total of 17,760 human rabies cases of China from 2005 to 2011. In our spatial analyses we used Gaussian kernel density analysis, average nearest neighbor distance, Spatial Temporal Density-Based Spatial Clustering of Applications with Noise and developed a model of rabies spatiotemporal spread. Human rabies cases increased from 2005 to 2007 and decreased during...
Advances in Parasitology, 2011
Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable map... more Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes.
Preventive Veterinary Medicine, 2011
Over the past two decades, the poultry sector in China went through a phase of tremendous growth ... more Over the past two decades, the poultry sector in China went through a phase of tremendous growth as well as rapid intensification and concentration. Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 was first detected in 1996 in Guangdong province, South China and started spreading throughout Asia in early 2004. Since then, control of the disease in China has relied heavily on wide-scale preventive vaccination combined with movement control, quarantine and stamping out. This strategy has been successful in drastically reducing the number of outbreaks during the past 5 years. However, HPAIV H5N1 is still circulating and is regularly isolated in traditional live bird markets (LBMs) where viral infection can persist, which represent a public health hazard for people visiting them. The use of social network analysis in combination with epidemiological surveillance in South China has identified areas where the success of current strategies for HPAI control in the poultry production sector may benefit from better knowledge of poultry trading patterns and the LBM network configuration as well as their capacity for maintaining HPAIV H5N1 infection. We produced a set of LBM network maps and estimated the associated risk of HPAIV H5N1 within LBMs and along poultry market chains, providing new insights into how live poultry trade and infection are intertwined. More specifically, our study provides evidence that several biosecurity factors such as daily cage cleaning, daily cage disinfection or manure processing contribute to a reduction in HPAIV H5N1 presence in LBMs. Of significant importance is that the results of our study also show the association between social network indicators and the presence of HPAIV H5N1 in specific network configurations such as the one represented by the counties of origin of the birds traded in LBMs. This new information could be used to develop more targeted and effective control interventions.
PLoS ONE, 2012
Background: The number of outbreaks of highly pathogenic avian influenza virus of the H5N1 subtyp... more Background: The number of outbreaks of highly pathogenic avian influenza virus of the H5N1 subtype (HPAIV H5N1) over the past 5 years has been drastically reduced in China but sporadic infections in poultry and humans are still occurring. In this study, we aimed to investigate seasonal patterns in the association between the movement of live poultry originating from southern China and HPAIV H5N1 infection history in humans and poultry in China.
Bulletin of the World Health Organization, 2011
Vietnam and Thailand in late 2003, causing severe mortality in affected flocks. Given that the vi... more Vietnam and Thailand in late 2003, causing severe mortality in affected flocks. Given that the virus has crossed the species barrier between poultry and humans and caused human fatalities, national governments and international agencies are intensively studying measures to control the spread of the disease. Among these strategic options would be 'restructuring' the poultry industry in ways that could threaten the livelihoods of smallholder backyard producers.
Food and Agriculture …, 2007
Because of human and livestock population growth, changes in livestock production, the emergence ... more Because of human and livestock population growth, changes in livestock production, the emergence of worldwide agro-food networks, and significant changes in personal mobility, human populations increasingly share a global commons of disease risk, among themselves and with domestic and wild animal species. To elucidate the linkage between livestock production and global public health, this paper draws upon recent experiences provided by different influenza A virus (IAV) incursions into domestic livestock populations, the most notable one being the ongoing HPAI H5N1 epidemic that originated in Asia, which now also affects Africa and which has led to outbreaks in the Near East and in Europe.
Scientific reports, 2015
Following rapid, global clonal dominance of hypervirulent ribotypes, Clostridium difficile now co... more Following rapid, global clonal dominance of hypervirulent ribotypes, Clostridium difficile now constitutes the primary infectious cause of nosocomial diarrhoea. Evidence indicates at least three possible mechanisms of hypervirulence that facilitates the successful invasion of these atypical strains: 1) increased infectiousness relative to endemic strains; 2) increased symptomatic disease rate relative to endemic strains; and 3) an ability to outcompete endemic strains in the host's gut. Stochastic simulations of an infection transmission model demonstrate clear differences between the invasion potentials of C. difficile strains utilising the alternative hypervirulence mechanisms, and provide new evidence that favours certain mechanisms (1 and 2) more than others (3). Additionally, simulations illustrate that direct competition between strains (inside the host's gut) is not a prerequisite for the sudden switching that has been observed in prevailing ribotypes; previously domi...
PLoS Neglected Tropical Diseases
Background Mapping the distribution of schistosomiasis is essential to determine where control pr... more Background Mapping the distribution of schistosomiasis is essential to determine where control programs should operate, but because it is impractical to assess infection prevalence in every potentially endemic community, model-based geostatistics (MBG) is increasingly being used to predict prevalence and determine intervention strategies. Methodology/Principal Findings To assess the accuracy of MBG predictions for Schistosoma haematobium infection in Ghana, school surveys were evaluated at 79 sites to yield empiric prevalence values that could be compared with values derived from recently published MBG predictions. Based on these findings schools were categorized according to WHO guidelines so that practical implications of any differences could be determined. Using the mean predicted values alone, 21 of the 25 empirically determined ‘high-risk’ schools requiring yearly praziquantel would have been undertreated and almost 20% of the remaining schools would have been treated despite ...
Australian Journal of Rural Health, 2011
Complementary and alternative medicine (CAM) use is high in rural health and an agenda for resear... more Complementary and alternative medicine (CAM) use is high in rural health and an agenda for research in the geography of CAM has been outlined. Unfortunately, no studies to date have mapped the geographic distribution of CAM practitioners in rural areas. For the first time we investigate CAM practitioner distributions across a large district/region in rural Australia. A CAM infrastructure audit of practitioners was performed in rural Divisions of General Practice in New South Wales, Australia. CAM providers form a significant part of the health care system in rural New South Wales with substantial representation across all degrees of rurality and in both under-serviced and well-serviced areas. CAM practitioners outnumbered GPs in four NSW Divisions of General Practice and in no Division numbered less than half of the total number of GPs. Given the challenges of access to and recruitment and retention of conventional health care providers in rural settings and the significant presence of CAM practitioners, it is possible to consider such practitioners as an untapped resource in rural health care delivery. Assuming appropriate regulatory and quality standards are in place this resource should attract careful attention as part of future rural health policy and planning. The significant presence and high prevalence of use of CAM practitioners should also serve as an impetus to reform CAM service delivery in Australia.
Malaria Journal, 2012
Background: Identifying and targeting hyper-endemic communities within meso-endemic areas constit... more Background: Identifying and targeting hyper-endemic communities within meso-endemic areas constitutes an important challenge in malaria control in endemic countries such like Angola. Recent national and global predictive maps of malaria allow the identification and quantification of the population at risk of malaria infection in Angola, but their small-scale accuracy is surrounded by large uncertainties. To observe the need to develop higher resolution malaria endemicity maps a predictive risk map of malaria infection for the municipality of Dande (a malaria endemic area in Northern Angola) was developed and compared to existing national and global maps, the role of individual, household and environmental risk factors for malaria endemicity was quantified and the spatial variation in the number of children at-risk of malaria was estimated. Methods: Bayesian geostatistical models were developed to predict small-scale spatial variation using data collected during a parasitological survey conducted from May to August 2010. Maps of the posterior distributions of predicted prevalence were constructed in a geographical information system. Results: Malaria infection was significantly associated with maternal malaria awareness, households with canvas roofing, distance to health care centre and distance to rivers. The predictive map showed remarkable spatial heterogeneity in malaria risk across the Dande municipality in contrast to previous national and global spatial risk models; large high-risk areas of malaria infection (prevalence >50%) were found in the northern and most eastern areas of the municipality, in line with the observed prevalence.
Background and Objective: In Nepal, gastrointestinal helminthiases are endemic in indigenous peop... more Background and Objective: In Nepal, gastrointestinal helminthiases are endemic in indigenous people living in low laying areas of the country. However, little is known regarding the role of different socio-economic indicators on helminth infections in these communities. The main aim of this study is to identify the relationship between socio-economic factors and helminth infection in an indigenous community in Nepal.
PLoS ONE, 2012
Background: Malaria, schistosomiasis and geohelminth infection are linked to maternal and child m... more Background: Malaria, schistosomiasis and geohelminth infection are linked to maternal and child morbidity and mortality in sub-Saharan Africa. Knowing the prevalence levels of these infections is vital to guide governments towards the implementation of successful and cost-effective disease control initiatives.
EcoHealth, 2014
A recent study in Western Australia identified area level associations between soil salinisation ... more A recent study in Western Australia identified area level associations between soil salinisation and hospital admissions for depression. Our study assessed the quantitative relationship between mental health measures at the individual level and location specific environmental measurements on salinity, as well as two other indicators of environmental degradation and change: land surface temperature and normalised difference vegetation index, a proxy for rainfall. Location-specific environmental measurements were linked to individual mental health scores of women in three age cohorts from the Australian Longitudinal Study on Women's Health using a geographic information system. Bayesian geostatistical linear regression models were developed to assess associations between environmental exposures and mental health scores of women. In contrast to previous studies using area level measures, our study found no associations between individual level measurements of mental health scores for women in south-west Western Australia and salinity, LST or NDVI.