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| Factors | Details | References |
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| Marsh, wetland, coastal area, swamp, etc. as the possible source of malaria infection | In the African countries, anopheline larvae were abundantly found in the swamps; and topographic wetness (of wetlands) was strongly associated with the spatial distribution of malaria infection cases. The control of wetlands is important for malaria elimination. | [34, 40, 56–62] |
| In the late Bronze to early Iron Age Europe, the occupation of the coastal marshes paved the way for the spreading of malaria. Mosquito larvae were able to grow up in stagnant pools and ditches of North Sea or Anglo-Saxon England coast marshes. In European history, the coastal marshes were generally hyperendemic for malaria during 16th to 18th century. |
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| Expansion of irrigation facilities | In Ancient Egypt and Rome, Fayum area became the granary by repeated projects of large-scale land reclamation and construction of canal system. Anopheles vector breeding was directly or indirectly linked to the presence of extensive irrigation system. Fayum was seriously exposed to the hazards of malaria by increasing contact between human beings and mosquitos that were bred in the newly developed irrigation system. | [2, 60] |
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| Reclamation of wetland for agriculture | The linkage of land reclamation and malaria infection was proven in East Africa. For instance, the elimination of papyrus from the wetlands during land reclamation promotes the breeding of mosquitos and malaria infection. Drainage ditches in newly claimed agricultural land were also the most common breeding site for mosquitos. In brief, the land reclamation was to foster mosquito reproduction by reduced vegetation cover and the elevation of the temperature at breeding site. | [2, 60, 124, 125] |
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| Intensified crop cultivation or economic specialization in agriculture | Epidemiological study showed that malaria transmission and intensified crops are highly related. The incidence of malaria is about ten times higher in cereals-cultivation area than in areas with less cereals. Intensity of crop cultivation is highly associated with exacerbated human risk of malaria. Specialization in agriculture initially influences on forest loss, and further induces malaria infection (by reducing the biodiversity due to a replacement of huge variety of vegetation with nonnative crops). | [2, 64, 124–127] |
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| Rice cultivation | The rice paddies provide abundant breeding opportunities for malaria mosquitos. It also becomes a challenging site for vector control. Improper drainage from rice paddies caused Anopheline mosquitos to breed. Mosquito control agents are difficult to be applied to rice paddies. Rice cultivation has a deep-rooted relationship with malaria transmission. | [124, 128–133] |
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| Deforestation | The pupation rate of Anopheles mosquito was the highest in the samples collected from deforested areas. Land cover pattern is a key factor that influences the habitat for malaria mosquitos. Relationship between deforestation caused by a small-scale farming and Anopheles mosquito breeding was evidently proven in Amazon region. | [60, 64, 65, 134–144] |
| In a structural equation model across 67 (developing) nations, positive association was observed between deforestation rates and malaria prevalence. In Sub-Saharan countries, living in the land without trees led to the increased risk of malaria infection. The relationship between land cover and the reproduction of malaria vector mosquitos was also shown in Western Kenyan Highlands. |
| Epidemiological aspects of ecosystem change (deforestation) and mosquito habitat proliferation (increased levels of larvae, mosquito populations, and actual malaria rates) have been studied extensively. Significant relationship was observed between the percentage of forest cover loss and higher infection prevalence of malaria. |
| Deforestation impacts malaria prevalence by multiple mechanisms: increase in the sunlight amount, warming temperature ideal for the pupation of malaria vector larvae, standing water after clearing terrain, the land becoming flatter and more likely to store water, which is typically less acidic and more conductive to Anopheles larvae development. |
| When the forest is replaced by new croplands, the plants still provide the bushy cover for mosquito proliferation, making the malaria infection prevalence higher. |
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| High population density | In developing countries, rural population growth and needs to increase food production induce the forest loss, further influencing malaria infection. Using the timbers for building and fuel wood is also one of the key causes of deforestation. Growing rural population also tend to live closer to the natural habitats of mosquitos, further experiencing risk of malaria infection. | [40, 64, 145–147] |
| In medieval city of Groningen, 10 percent of the urban population died while the surrounding countryside showed a death rate of 5 percent. |
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