@phdthesis{Ngom2010, author = {Roland Ngom}, title = {Spatial and Statistical Prediction of Urban Malaria in Yaound{\´e}: A Social and Environmental Modelling Approach for Health Promotion}, url = {https://nbn-resolving.org/urn:nbn:de:bsz:he76-opus-75212}, year = {2010}, abstract = {Most of the existing predictive malaria risks models use very broad spatial scales. They are usually built for continental or national outlines. These models do not account for the complexity of socio-economic variables intervening in the malaria transmission process. Most of them are driven by weather data. However, it is difficult to make antimalarial interventions at a continental or national level and to act on climate variables alone. Consequently, the suitability of these models for real malaria prevention strategies is not high. Moreover, the existing informational-based prevention strategies are not suitable, since they are usually limited to the occasional usage of large public mass media to transfer bits of information. This study proposes new paths in malaria modelling and prevention. It is dedicated to the building of a thematically extended model integrating both environmental and social variables. The proposed prevention strategy is based on an educational philosophy integrating the actual malaria modelling results. The study starts with the implementation of a methodology dedicated to data creation and data analysis. The protocol of data creation is based on an urban malaria paradigm. It encompasses the epidemiological, environmental, and social components of malaria risk. The epidemiological component is elaborated through retrospective, self-reported, malaria febrile and clinical episodes of individuals at the household level. In addition to climate data, key ecological variables are created from remote sensing sources with a very high spatial resolution. New social indexes and coefficients measuring economic status, crowding conditions and prevention capacity of the population are created. A morphospatial structure of Yaound{\´e}, which assumes the presence of distinct population aggregates, representing similar socio-economic profiles, is established using an object-oriented classification of QuickBird images. A spatial based index of urbanity (IU), quantitatively marking the difference between “urban” and “rural” patterns, is also built. A knowledge-base expressing the social, ecological and malarial significance of both population aggregates and index of urbanity is established and used in a Fuzzy Logic simulation approach to predict urban malaria in Yaound{\´e}. The yearly malaria prevalence based on individuals in households in Yaound{\´e} is 9\% while the malaria prevalence based on households as an entity is 27\%. Malaria prevalence is higher during the small rainy season. It is much more marked in peri-urban areas during this season, while people in central areas are more exposed during the big rainy season. A statistical multinomial model identified socio-economic and socio-ecologic variables, notably those related to the physical condition of houses, as being highly associated with frequent episodes of malaria in households. Variables related to prevention capacity perform very well in predicting the absence of malaria in households. Among the ecological variables, only elevation and the distance to urban agriculture (UA) areas are associated with malaria. The statistically (from multinomial models), overall-predicted household prevalence of malaria is lower than the observed one. The morphospatial structure of the city shows a clear distinction between very dense, centralized and “urbanized” population aggregates (PA) and very isolated, mostly peri-urban, “rural” population aggregates. The morphological model suggests that the intensity and sustainability of the malaria transmission are both dependant on demographical gradients. The less urbanized population aggregates, although being in proximity of urban agriculture areas, are demographically not suitable for a sustainable malaria transmission. The most urbanized population aggregates are too dense and too far from urban agriculture areas. This does not favour local malaria transmission. This rigid ecological pattern is somewhat biased by the identified social patterns. The densest population aggregates mostly host very poor people. This allows a part of this population to be at a high risk of malaria through localized urban farming activities. The other parts of dense population aggregates are located in centrally situated planned zones. They have better socio-economic and socio-ecologic conditions which significantly reduces their vulnerability to malaria. Population aggregates with suitable demographic conditions (not too dense or too isolated), in addition to a higher environmental and social vulnerability, are the most exposed. Although the Fuzzy Logic simulation procedure produces a predicted prevalence which is lower than that of the overall multinomial model, it also identifies these intermediate population aggregates as being the most exposed. Results of interviews show that, in general, the knowledge and perception of people of basic key factors associated with malaria transmission is bad. Moreover, this knowledge follows a social stratification with the richest people having the best background. An association between knowledge and prevention behaviour is also established. In order to use the model for malaria prevention, three educational game-based tools have been created. The tools are designed for different target audiences with regard to required support and cognitive capacities. A follow-up method based on a pre- and post-test, before- and after-, play sessions is used to measure the information transfer capacity of each game to players who had various social profiles. Until now, official antimalarial campaigns in Cameroon used other media such as posters, television, and paper journals. Games had been not used at all before. From the point of view of players, the proposed games are highly attractive. Among them, the computer-based one, mixing visual and audio cognitive aspects in the information transfer, shows a good information transfer capacity. Furthermore, the degree of progress in the acquisition of malaria relevant information is highly dependent on the frequency of play.}, language = {en} }