Malaria risk cartography in the municipality of Maxixe: Case of the Chambone Neighborhood

This article focuses on the assessment of malaria risk spatialization, based on data from residential areas by type of breeding sites in the Chambone neighborhood (Maxixe, Mozambique). For the operationalization of the objectives, we opted, in addition to the bibliographic review, for a quali-quantitative approach, for accompanied observations and surveys. The results reveal that the areas at high risk of malaria in Chambone are the extreme northeast, center-eastern, southern and inland southwest-central. These high-risk areas, according to the reclassification given by kernel density, are of higher concentration of breeding sites and dwellings. Given the diversity in the spatial distribution pattern of risk and the factors with conditioning factors, taking into account the type of planning for all areas of the Chambone neighborhood, it was feasible to develop plans adjusted to local interests to modify the current spatial pattern of malaria risk distribution.


INTRODUCTION
Malaria is an infectious, febrile, acute or chronic, systemic, non-contagious disease caused by parasites of the genus Plasmodium and transmitted by the bite of the Anopheles mosquito (Ávila, 1996;Garcia et al, 2009;Nweti, 2010). In Mozambican territory, this parasite is responsible for about 90% of malaria cases and can be transmitted to men and women of all ages. According to Roll Back Malaria (RBM, 2008(RBM, , 2014 and WHO (2014)  Source: WHO (2014) In Mozambique, malaria affects communities in poor rural and urban areas more by the lack of information and precautionary measures, with high transmission rates and difficulties in accessing basic health services, thus leading to the death of about 3.9% of the infant Malaria risk cartography in the municipality of Maxixe: Case of the Chambone Neighborhood www.nucleodoconhecimento.com.br population and 6.2% of the adult population (WHO, 2004). Mozambique is considered a territory at risk of malaria, due to its geographical location: in a tropical region where malaria is an endemic disease resulting from the favoring of the climate in its transmission in the soon to almost every year, reaching its maximum peak after the rainy season (December to April).
This issue is reflected in the intensity of transmission that varies from year to year and from region to region, depending on temperature, precipitation and altitude. However, some dry areas of the national territory are considered to be little prone to the epidemic and there was, in 2008, the hope that by 2011 the malaria vaccine would be available to save lives (MISAU, 2008  The surveys were extracted from a universe of about 2,500 households. To validate the characteristics of the place, maps, graphs, tables and other secondary data related to malaria risk were elaborated. Therefore, the stages of carrying out the activities of this research, illustrated in the flowchart (figure 32345) are presented in a syntheti [3]c wa y:     Source: Author (2017) Continuing, (iv) refers to the way in which housing is built, which can contribute significantly to the spread of the malaria-causing mosquito, due to the lack of windows and walls in some  The analysis of spatial information requires a particularity depending on the typology of the data to be presented, and these can be points (location of the breeding sites) and the areas with counting (number of dwellings). The representation by a housing surface, classified from the density levels that alternate according to color and tonality, was interpreted as follows: red means very high density; orange indicates high density; yellow refers to average density; the green with lighter tint concerns the low density and the green with darker tint denotes a very low density. The surface generated in relation to the population presents values from 0 to more than 2500 inhabitants per square kilometer (hab/km²), as shown in Figure 6. The northern-central-southern end of the eastern part of the Chambone district, has a higher concentration of dwellings, which means very high and high population density and ranges from 1000 to more than 2500 inhabitants/km². This very high and high population density is due to the fact that it is an urban area, where the headquarters of the municipality of Maxixe is located, which has a higher population concentration when compared to other areas.
Further into the interior of the neighborhood, specifically in the extreme southwest in relation to the most urbanized area, we find a small cluster that constitutes an area of high and medium density, with variations from 500 to 2500 inhabitants/km².  (04) breeding sites of densities, distributed by 332 georeferenced points and defined by proximity/neighborhood ranging from 0 to more than 100 breeding sites, with the following attribution: red means very high density; orange indicates high density; green with lighter tint implies medium density and green with darker tint refers to low density. Analyzing the map of the spatial distribution pattern of the density of breeding sites, it is perceived that these are distributed in almost the entire Chambone neighborhood, and the areas of very high density (more than 100) and high density (50 to 100) of breeding sites are at the northern-central extreme. To analyze the density situation of breeding sites per km² in the study area, we started to   There was a need for the reclassification of the dwellings using the kernel density map of the proximity of dwellings, presenting densities levels (1 to 5), and level five, represented by the red color, indicates the greatest proximity between the dwellings in the Chambone neighborhood ( figure 9). This proximity or neighborhood of housing shows a greater concentration of the population in these areas, an essential indicator that requires attention in the process of analyzing the risk of malaria. The concern with spatial analysis for the present study served as a tool to georeference the risk areas of the Chambone neighborhood and to identify the factors associated with the spatial pattern of malaria risk.
It is in this order of ideas that the exact location of risk areas, distance between breeding sites or outbreaks of malaria and housing was sought. The evidence of the location of concentrations of a greater number of breeding sites in or near housing areas is fundamental to the analysis at the neighborhood level, which allows the identification of priority areas for intervention by local authorities. This information is classified through other data aggregates, because, in the observations, references are always found to identify and qualify the study area. A set of spatial information on epidemiological risk may include not only observations of health events, but also information about the place where they were collected (BARATA, 1997), that is, in addition to the physical environment, their complex interactions with social, cultural and economic aspects of the place can be taken. This result illustrates that these areas have a higher concentration of breeding sites and dwellings, thus establishing high-risk areas, according to the reclassification given by kernel density. To provide more subsidies to the spatial distribution of malaria risk in the Chambone neighborhood, we opted for the use of an image chart to illustrate the high-risk areas concentrated in the extreme northeast, central-eastern, southwest and southern ( Figure 11). This is some evidence of the socio-environmental reality of the study area. In the extreme northeast is a pond covered with vegetation of reed, grass and shrubs. This lagoon has continuity along the eastern coast, consisting of a vegetation of mangrove and small shrubs, interspersed by stagnant waters, dumpsters, tires used as vegetation, among others.   In Mozambique, malaria is endemic throughout the territory and most of the population lives in areas at high risk of malaria infection due to factors that contribute to endemicity, namely: climatic and environmental conditions, favorable temperatures, precipitation pattern, places conducive to vector propagation, the socioeconomic situation of most of the population related to poverty , inappropriate housing and inaccessible means of prevention (PNCM, 2007). The assessment of the risk of malaria in the Chambone neighborhood was first characterized by socio-environmental characterization and obtaining breeding sites or outbreaks of malaria, and then the identification of risk areas was made. Linked to this was the production of malaria risk spatialization maps in the Chambone neighborhood. These were some of the questions that permeated this study.
This generation of cartographic products to illustrate the spatialization of malaria risk serves as a fundamental tool for competent local authorities, managers and community health agents, allowing the definition of mitigation and control actions in areas considered to be at high risk of malaria.