Risk factors and housing effect on malaria infection: A case-control study

Background: This study aims to demonstrate the different risk factors between low and high endemicity area and housing effect on malaria infection. Methods: This study is a case-control study with a ratio of 1:2 comparing low (Jambi) and high (Sumba) endemicity areas. Initial screening of malaria was done to assign cases and controls following inclusion criteria. The selected cases and controls were then assessed with a structured questionnaire in relation to risk factors of malaria infection. Additionally, to discover the impact of house type on malaria infection, a total of 72 houses was observed in a series of six weeks (between 28 June and 12 August 2018) human landing catch (HLC) observations that includes three types of houses; malaria, non-malaria, and permanent dwellings. The HLC was done indoors and outdoors for each house type each night. A weekly screening was taken to monitor the malaria infection rate of each house type. Results: Jambi and Sumba shared several similar individual and environmental risk factors. However, agricultural activity or visiting forestry areas is a protective factor for malaria infection in Jambi but is a risk factor in Sumba. The general linear mixed univariate model result indicates the difference in risk factor variables between Jambi and Sumba. The entomological survey found that only malaria houses significantly differed in the number of means collected mosquitoes compared with the other type of houses. Weekly screening found that the incidence rate of malaria houses is highest among others. Conclusion: The risk factors are inevitably crucial for malaria prevention strategy. Risk factor management needs to consider the location where the endemicity level may differ for each risk factor, and housing improvement is not a proper strategy before controlling other environmental factors.