GEOMED 2013 – From spatial analysis to public health practice
Publication date: July 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 10 Author(s): Ravi Maheswaran , Mark Strong (Source: Spatial and Spatio-temporal Epidemiology)
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Neighborhood geographic disparities in heart attack and stroke mortality: Comparison of global and local modeling approaches
This study investigated neighborhood geographic disparities in myocardial infarction (MI) and stroke mortality risks in middle Tennessee and identified determinants of observed disparities. Descriptive and spatial analyses were performed on MI and stroke mortality data covering the time period 1999–2007. Besag, York and Molliè (BYM) model was used to investigate spatial patterns. Global (BYM) and local models [Poisson Geographically Weighted Generalized Linear Models (GWGLM)] were used to investigate determinants of the identified spatial patterns. Significant (p <0.05) differences in mortality risks by...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Estimation of district-level under-5 mortality in Zambia using birth history data, 1980–2010
In this study we consider different methods for analyzing birth history data in combination with various small area models. We construct a simulation environment to assess the performance of different combinations of birth history methods and small area models in terms of bias, efficiency, and coverage. We find that performance is highly dependent on the birth history method applied and how temporal trends are accounted for. We estimated trends in district-level under-5 mortality in Zambia from 1980 to 2010 using the best-performing model. We find that under-5 mortality is highly variable within Zambia: there was a 1.8-fol...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

A multivariate CAR model for mismatched lattices
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Aaron T. Porter , Jacob J. Oleson In this paper, we develop a multivariate Gaussian conditional autoregressive model for use on mismatched lattices. Most current multivariate CAR models are designed for each multivariate outcome to utilize the same lattice structure. In many applications, a change of basis will allow different lattices to be utilized, but this is not always the case, because a change of basis is not always desirable or even possible. Our multivariate CAR model allows each outcome to have a different neigh...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Supervised learning and prediction of spatial epidemics
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Gyanendra Pokharel , Rob Deardon Parameter estimation for mechanistic models of infectious disease can be computationally intensive. Nsoesie et al. (2011) introduced an approach for inference on infectious disease data based on the idea of supervised learning. Their method involves simulating epidemics from various infectious disease models, and using classifiers built from the epidemic curve data to predict which model were most likely to have generated observed epidemic curves. They showed that the classification approa...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Spatio-temporal epidemiology of highly pathogenic avian influenza (subtype H5N1) in poultry in eastern India
This study aimed to identify disease clusters and risk factors of HPAI H5N1 in these states, for targeted surveillance and disease control. A spatial scan statistic identified two significant disease clusters in West Bengal and Assam, occurring during January and November–December 2008, respectively. Key risk factors were identified at sub-district level using bootstrapped logistic regression and boosted regression trees model. With both methods, HPAI H5N1 outbreaks in backyard poultry were associated with accessibility in terms of time taken to access a city with >50,000 persons, human population density and ...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

The use of sampling weights in Bayesian hierarchical models for small area estimation
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Cici Chen , Jon Wakefield , Thomas Lumely Hierarchical modeling has been used extensively for small area estimation. However, design weights that are required to reflect complex surveys are rarely considered in these models. We develop computationally efficient, Bayesian spatial smoothing models that acknowledge the design weights. Computation is carried out using the integrated nested Laplace approximation, which is fast. An extensive simulation study is presented that considers the effects of non-response and non-random...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Geographic access to healthy and unhealthy food sources for children in neighbourhoods and from elementary schools in a mid-sized Canadian city
We examined location-related accessibility to healthy and unhealthy food sources for school going children in Saskatoon, Saskatchewan. We compared proximity to food sources from school sites and from small clusters of homes (i.e., dissemination blocks) as a proxy for home location. We found that (1) unhealthy food sources are more prevalent near schools in lower income than higher income neighbourhoods; (2) unhealthy compared to healthy food sources are more accessible from schools as well as from places of residence; and (3) while some characteristics of neighbourhood low socio-economic status are associated with less acc...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Spatial prevalence and associations among respiratory diseases in Maine
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Christopher Farah , H. Dean Hosgood III , Janet M. Hock Chronic respiratory diseases rank among the leading global disease burdens. Maine’s respiratory disease prevalence exceeds the US average, despite limited urbanization/industrialization. To provide insight into potential etiologic factors among this unique, rural population, we analyzed the spatial distributions of, and potential associations among asthma, COPD, pneumonia, and URI adult outpatient data (n =47,099) from all outpatient transactions (n =5,052,900)...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Modeling sheep pox disease from the 1994–1998 epidemic in Evros Prefecture, Greece
We present data from sheep pox epidemics which occurred between 1994 and 1998. The data include weekly records of infected farms as well as a number of covariates. We implement Bayesian stochastic regression models which, in addition to various explanatory variables like seasonal and environmental/meteorological factors, also contain serial correlation structure based on variants of the Ornstein–Uhlenbeck process. We take a predictive view in model selection by utilizing deviance-based measures. The results indicate that seasonality and the number of infected farms are important predictors for sheep pox incidence. (S...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

The rubber plantation environment and Lassa fever epidemics in Liberia, 2008–2012: A spatial regression
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Babasola O. Olugasa , John B. Dogba , Bamidele Ogunro , Eugene A. Odigie , Jomah Nykoi , Johnson F. Ojo , Olalekan Taiwo , Abraham Kamara , Charles K. Mulbah , Ayotunde J. Fasunla As Lassa fever continues to be a public health challenge in West Africa, it is critical to produce good maps of its risk pattern for use in active surveillance and control intervention. We identified eight spatial features related to the rubber plantation environment and used them as explanatory variables for Lassa fever (LF) outbreaks on the Un...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Optimal vaccination strategies against vector-borne diseases
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Kaare Græsbøll , Claes Enøe , René Bødker , Lasse Engbo Christiansen Using a process oriented semi-agent based model, we simulated the spread of Bluetongue virus by Culicoides, biting midges, between cattle in Denmark. We evaluated the minimum vaccination cover and minimum cost for eight different preventive vaccination strategies in Denmark. The simulation model replicates both a passive and active flight of midges between cattle distributed on pastures and cattle farms in Denmark. A sea...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Spatial and statistical methodologies to determine the distribution of dengue in Brazilian municipalities and relate incidence with the Health Vulnerability Index
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): Misael Enrique Oviedo Pastrana , Rachel Lage Brito , Rafael Romero Nicolino , Camila Stefanie Fonseca de Oliveira , João Paulo Amaral Haddad Dengue fever is among the most important emerging infectious diseases in the world, and in recent years it has been a source of public concern for the public health control systems of many tropical and subtropical countries. Thus, the purpose of this study was to apply spatial and statistical methodologies to analyze the geographic distribution of dengue and to relate its inci...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Spatio-temporal modeling of the African swine fever epidemic in the Russian Federation, 2007–2012
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): F.I. Korennoy , V.M. Gulenkin , J.B. Malone , C.N. Mores , S.A. Dudnikov , M.A. Stevenson In 2007 African swine fever (ASF) entered Georgia and in the same year the disease entered the Russian Federation. From 2007 to 2012 ASF spread throughout the southern region of the Russian Federation. At the same time several cases of ASF were detected in the central and northern regions of the Russian Federation, forming a northern cluster of outbreaks in 2011. This northern cluster is of concern because of its proximity to mainlan...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Using exceedance probabilities to detect anomalies in routinely recorded animal health data, with particular reference to foot-and-mouth disease in Viet Nam
Publication date: October 2014 Source:Spatial and Spatio-temporal Epidemiology, Volume 11 Author(s): K.K. Richards , M.L. Hazelton , M.A. Stevenson , C.Y. Lockhart , J. Pinto , L. Nguyen The widespread availability of computer hardware and software for recording and storing disease event information means that, in theory, we have the necessary information to carry out detailed analyses of factors influencing the spatial distribution of disease in animal populations. However, the reliability of such analyses depends on data quality, with anomalous records having the potential to introduce significant bias and lead to inap...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

Landscape risk factors for Lyme disease in the eastern broadleaf forest province of the Hudson River valley and the effect of explanatory data classification resolution
This study assessed how landcover classification affects associations between landscape characteristics and Lyme disease rate. Landscape variables were derived from the National Land Cover Database (NLCD), including native classes (e.g., deciduous forest, developed low intensity) and aggregate classes (e.g., forest, developed). Percent of each landcover type, median income, and centroid coordinates were calculated by census tract. Regression results from individual and aggregate variable models were compared with the dispersion parameter-based R 2 ( R α 2 ) and AIC. The maximum R α 2 was 0.82 and 0.83...
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research

The association between the density of retail tobacco outlets, individual smoking status, neighbourhood socioeconomic status and school locations in New South Wales, Australia
Conclusion Policymakers could consider exploring a range of strategies that target tobacco outlets in proximity to schools, in more disadvantaged neighbourhoods and in areas of existing high tobacco outlet density. (Source: Spatial and Spatio-temporal Epidemiology)
Source: Spatial and Spatio-temporal Epidemiology - November 20, 2014 Category: Epidemiology Source Type: research