System and market failures: the unavailability of magnesium sulphate for the treatment of eclampsia and pre-eclampsia in Mozambique and Zimbabwe.

Low cost and effective drugs, such as magnesium sulphate, need to be included in initiatives to improve access to essential medicines in Afric

School Flexible Learning Spaces, Student Movement Behavior and Educational Outcomes among Adolescents: A Mixed-Methods Systematic Review

BACKGROUND: To achieve sustainability, we must consider scalable improvements in student movement behavior in the classroom setting, educational priorities. Flexible learning spaces that employ student‐centered pedagogy and contain a range of furniture and layout options, implemented to improve educational outcomes, may enable unintended health benefits. In this review, we summarize the evidence on the effects of flexible learning spaces on adolescent student movement behaviors and educational outcomes. METHODS: We searched 5 databases, retrieving 5 quantitative and one qualitative article meeting the review criteria. RESULTS: Students in flexible learning spaces spent less time sitting, and more time standing and moving. Students were also more engaged, on‐task, and collaborated and interacted more. Academic results for English, Mathematics and Humanities for those in flexible learning spaces were higher than peers in traditional classrooms. CONCLUSION: Evidence from the reviewed studies suggests that there may be beneficial outcomes across some movement behaviors as well as learning outcomes in classrooms that employ student‐centered pedagogy and use a built environment that facilitates autonomy and choice around where and how to learn. These learning environments present an opportunity for an interdisciplinary approach to address sedentary behavior in classrooms

Meningococcal Meningitis and Coal Mining in Provincial England: Geographical Perspectives on a Major Epidemic, 1929–33

This article presents the first systematic study of the spatial transmission of the 1929–33 epidemic of meningococcal meningitis and its association with local coal mining communities in three adjacent high incidence counties of England; Nottinghamshire, Derbyshire, and the West Riding of Yorkshire. Drawing on a robust method of spatial epidemiological analysis (swash‐backwash model), we demonstrate a gradient response with local levels of employment in coal mining for each of three key parameters of the epidemic wave: spatial velocity of transmission; duration of infectivity; and spatial reach. Partial least squares regression analysis identifies the relatively young and fertile demographic of local mining communities as the principal determinant of the resulting epidemic burden. Other sociodemographic parameters, including established risk factors for invasive meningococcal disease (low social class, high residential density, and overcrowding) are found to play little, or no, role in the spatial distribution of the disease. Our findings have importance for understanding the historic links between the coal mining industry and epidemic meningococcal meningitis, and point to possible present‐day opportunities for intervention through the designation of coal mining communities as defined risk groups for meningococcal vaccines

Meningococcal Meningitis and Coal Mining in Provincial England: Geographical Perspectives on a Major Epidemic, 1929–33

This article presents the first systematic study of the spatial transmission of the 1929–33 epidemic of meningococcal meningitis and its association with local coal mining communities in three adjacent high incidence counties of England; Nottinghamshire, Derbyshire, and the West Riding of Yorkshire. Drawing on a robust method of spatial epidemiological analysis (swash‐backwash model), we demonstrate a gradient response with local levels of employment in coal mining for each of three key parameters of the epidemic wave: spatial velocity of transmission; duration of infectivity; and spatial reach. Partial least squares regression analysis identifies the relatively young and fertile demographic of local mining communities as the principal determinant of the resulting epidemic burden. Other sociodemographic parameters, including established risk factors for invasive meningococcal disease (low social class, high residential density, and overcrowding) are found to play little, or no, role in the spatial distribution of the disease. Our findings have importance for understanding the historic links between the coal mining industry and epidemic meningococcal meningitis, and point to possible present‐day opportunities for intervention through the designation of coal mining communities as defined risk groups for meningococcal vaccines

Testing for Network and Spatial Autocorrelation

Testing for dependence has been a well-established component of spatial statistical analyses for decades. In particular, several popular test statistics have desirable properties for testing for the presence of spatial autocorrelation in continuous variables. In this paper we propose two contributions to the literature on tests for autocorrelation. First, we propose a new test for autocorrelation in categorical variables. While some methods currently exist for assessing spatial autocorrelation in categorical variables, the most popular method is unwieldy, somewhat ad hoc, and fails to provide grounds for a single omnibus test. Second, we discuss the importance of testing for autocorrelation in data sampled from the nodes of a network, motivated by social network applications. We demonstrate that our proposed statistic for categorical variables can both be used in the spatial and network setting

The dynamics of measles in sub-Saharan Africa.

Although vaccination has almost eliminated measles in parts of the world, the disease remains a major killer in some high birth rate countries of the Sahel. On the basis of measles dynamics for industrialized countries, high birth rate regions should experience regular annual epidemics. Here, however, we show that measles epidemics in Niger are highly episodic, particularly in the capital Niamey. Models demonstrate that this variability arises from powerful seasonality in transmission-generating high amplitude epidemics-within the chaotic domain of deterministic dynamics. In practice, this leads to frequent stochastic fadeouts, interspersed with irregular, large epidemics. A metapopulation model illustrates how increased vaccine coverage, but still below the local elimination threshold, could lead to increasingly variable major outbreaks in highly seasonally forced contexts. Such erratic dynamics emphasize the importance both of control strategies that address build-up of susceptible individuals and efforts to mitigate the impact of large outbreaks when they occur

Spread pattern of the first dengue epidemic in the city of Salvador, Brazil

<p>Abstract</p> <p>Background</p> <p>The explosive epidemics of dengue that have been occurring in various countries have stimulated investigation into new approaches to improve understanding of the problem and to develop new strategies for controlling the disease. The objective of this study was to evaluate the characteristics of diffusion of the first dengue epidemic that occurred in the city of Salvador in 1995.</p> <p>Methods</p> <p>The epidemiological charts and records of notified cases of dengue in Salvador in 1995 constituted the source of data. The cases of the disease were georeferenced according to census areas (spatial units) and epidemiological weeks (temporal unit). Kernel density estimation was used to identify the pattern of spatial diffusion using the R-Project computer software program.</p> <p>Results</p> <p>Of the 2,006 census areas in the city, 1,400 (70%) registered cases of dengue in 1995 and the spatial distribution of these records revealed that by the end of 1995 practically the entire city had been affected by the virus, with the largest concentration of cases occurring in the western region, composed of census areas with a high population density and predominantly horizontal residences compared to the eastern region of the city, where there is a predominance of vertical residential buildings.</p> <p>Conclusion</p> <p>The pattern found in this study shows the characteristics of the classic process of spreading by contagion that is common to most infectious diseases. It was possible to identify the epicenter of the epidemic from which centrifugal waves of the disease emanated. Our results suggest that, if a more agile control instrument existed that would be capable of rapidly reducing the vector population within a few days or of raising the group immunity of the population by means of a vaccine, it would theoretically be possible to adopt control actions around the epicenter of the epidemic and consequently reduce the incidence of the disease in the city. This finding emphasizes the need for further research to improve the technology available for the prevention of this disease.</p

The mortality rates and the space-time patterns of John Snow’s cholera epidemic map

Background Snow’s work on the Broad Street map is widely known as a pioneering example of spatial epidemiology. It lacks, however, two significant attributes required in contemporary analyses of disease incidence: population at risk and the progression of the epidemic over time. Despite this has been repeatedly suggested in the literature, no systematic investigation of these two aspects was previously carried out. Using a series of historical documents, this study constructs own data to revisit Snow’s study to examine the mortality rate at each street location and the space-time pattern of the cholera outbreak. Methods This study brings together records from a series of historical documents, and prepares own data on the estimated number of residents at each house location as well as the space-time data of the victims, and these are processed in GIS to facilitate the spatial-temporal analysis. Mortality rates and the space-time pattern in the victims’ records are explored using Kernel Density Estimation and network-based Scan Statistic, a recently developed method that detects significant concentrations of records such as the date and place of victims with respect to their distance from others along the street network. The results are visualised in a map form using a GIS platform. Results Data on mortality rates and space-time distribution of the victims were collected from various sources and were successfully merged and digitised, thus allowing the production of new map outputs and new interpretation of the 1854 cholera outbreak in London, covering more cases than Snow’s original report and also adding new insights into their space-time distribution. They confirmed that areas in the immediate vicinity of the Broad Street pump indeed suffered from excessively high mortality rates, which has been suspected for the past 160 years but remained unconfirmed. No distinctive pattern was found in the space-time distribution of victims’ locations. Conclusions The high mortality rates identified around the Broad Street pump are consistent with Snow’s theory about cholera being transmitted through contaminated water. The absence of a clear space-time pattern also indicates the water-bourne, rather than the then popular belief of air bourne, nature of cholera. The GIS data constructed in this study has an academic value and would cater for further research on Snow’s map

Suspected Motor Problems and Low Preference for Active Play in Childhood Are Associated with Physical Inactivity and Low Fitness in Adolescence

Background - This prospective longitudinal study investigates whether suspected motor problems and low preference for active play in childhood are associated with physical inactivity and low cardiorespiratory fitness in adolescence. Methodology/Principal Findings - The study sample consisted of the Northern Finland Birth Cohort 1986 (NFBC 1986) composed of 5,767 children whose parents responded to a postal inquiry concerning their children's motor skills at age 8 years and who themselves reported their physical activity at age 16 years. Cardiorespiratory fitness was measured with a cycle ergometer test at age 16 years. Odds ratios (OR) and their 95% confidence intervals (95% CI) for the level of physical activity and fitness were obtained from multinomial logistic regression and adjusted for socio-economic position and body mass index. Low preference for active play in childhood was associated with physical inactivity (boys: OR 3.31, 95% CI 2.42–4.53; girls: OR 1.79, 95% CI 1.36–2.36) and low cardiorespiratory fitness (boys: OR 1.87, 95% CI 1.27–2.74; girls: OR 1.52, 95% CI 1.09–2.11) in adolescence. Suspected gross (OR 2.16, 95% CI 1.33–3.49) and fine (OR 1.88, 95% CI 1.35–2.60) motor problems were associated with physical inactivity among boys. Children with suspected motor problems and low preference for active play tended to have an even higher risk of physical inactivity in adolescence. Conclusions/Significance - Low preference for active play in childhood was associated with physical inactivity and low cardiorespiratory fitness in adolescence. Furthermore, children with suspected motor problems and low preference for active play tended to have an even higher risk of physical inactivity in adolescence. Identification of children who do not prefer active play and who have motor problems may allow targeted interventions to support their motor learning and participation in active play and thereby promote their physical activity and fitness in later life.peerReviewe