Hugo Saba

Spatio-temporal correlation networks of dengue in the state of Bahia

BackgroundDengue is a public health problem that presents complexity in its dissemination. The physical means of spreading and the dynamics of the spread between municipalities need to be analyzed to guide effective public policies to combat this problem.MethodsThis study uses timing varying graph methods (TVG) to construct a correlation network between occurrences of reported cases of dengue between cities in the state of Bahia-Brazil. The topological network indices of all cities were correlated with dengue incidence using Spearman correlation. A randomization test was used to estimate the significance value of the correlation.ResultsThe correlation network presented a complex behavior with a heavy-tail distribution of the network edges weight. The randomization test exhibit a significant correlation (Pxa0<xa00.0001) between the degree of each municipality in the network and the incidence of dengue in each municipality.ConclusionsThe hypothesis of the existence of a correlation between the occurrences of reported cases of dengue between different municipalities in the state of Bahia was validated. The significant correlation between the node degree and incidence, indicates that municipalities with high incidence are also responsible for the spread of the disease in the state. The method proposed suggests a new tool in epidemiological control strategy.

Relevance of transportation to correlations among criticality, physical means of propagation, and distribution of dengue fever cases in the state of Bahia

Dengue infection is a public health problem with a complex distribution. The physical means of propagation and the dynamics of diffusion of the disease between municipalities need to be analysed to direct efficient public policies to prevent dengue infection. The present study presents correlations of occurrences of reported cases of dengue infection among municipalities, self-organized criticality (SOC), and transportation between areas, identifying the municipalities that play an important role in the diffusion of dengue across the state of Bahia, Brazil. The significant correlation found between the correlation network and the SOC demonstrates that the pattern of intramunicipal diffusion of dengue is coupled to the pattern of synchronisation between the municipalities. Transportation emerges as influential in the dynamics of diffusion of epidemics by acting on the aforementioned variables.

Self-affinity in the dengue fever time series

Dengue is a complex public health problem that is common in tropical and subtropical regions. This disease has risen substantially in the last three decades, and the physical symptoms depict the self-affine behavior of the occurrences of reported dengue cases in Bahia, Brazil. This study uses detrended fluctuation analysis (DFA) to verify the scale behavior in a time series of dengue cases and to evaluate the long-range correlations that are characterized by the power law α exponent for different cities in Bahia, Brazil. The scaling exponent (α) presents different long-range correlations, i.e. uncorrelated, anti-persistent, persistent and diffusive behaviors. The long-range correlations highlight the complex behavior of the time series of this disease. The findings show that there are two distinct types of scale behavior. In the first behavior, the time series presents a persistent α exponent for a one-month period. For large periods, the time series signal approaches subdiffusive behavior. The hypothesis of the long-range correlations in the time series of the occurrences of reported dengue cases was validated. The observed self-affinity is useful as a forecasting tool for future periods through extrapolation of the α exponent behavior. This complex system has a higher predictability in a relatively short time (approximately one month), and it suggests a new tool in epidemiological control strategies. However, predictions for large periods using DFA are hidden by the subdiffusive behavior.

E-Flow: A solution of Workflow for integration of the management of processes with the documentation of quality using XML

The extracted information of the workflow are similar to information about the quality document. The redundancy on this information brings necessity of a environment that integrates the quality management system with the workflow system. The project objectives are the specification and implementation of the e-flow, it contemplates the integration proposal previously. For that, will be proposed a metalanguage, represented by XML, that approaches the basic attributes referring the documentation of the quality ISO 9000.

Nonlocal dispersal of dengue in the state of Bahia

Abstract Dengue is an arbovirus that has spread throughout different, especially tropical and subtropical, regions of the world. This disease affects humans through mosquito bites. The occurrence of dengue epidemics has increased alarmingly over the last three decades. To detect a pattern regarding the dispersal process of dengue, this research presents a computational model based on three pillars: complex networks, time-varying graphing (TVG), and time-series synchronisation. To establish the synchronisation networks, the Motif-Synchronisation method with TVG was applied to a time series analysis of georeferenced dengue incidence data from the municipalities of Bahia from 2001 to 2016. After applying the model presented in this work, the dispersal behaviour patterns of these epidemics were found amongst the municipalities within Bahia, when synchronised, in epidemic moments. The results indicate that the incidence of dengue is not directly related to the distance between municipalities; rather, a time relation exists regarding the development of the vector and its capacity to transmit disease. The purpose of this model is to contribute to public disease interventions by providing early information.