Factors associated with persistent malaria transmission in urban peripheral areas in Dar Es Salaam Region, Mainland Tanzania

Abstract

ABSTRACT Background: In 2018, there were an estimated 219 million cases and 435,000 deaths of malaria globally. Africa Region bear the highest burden with an estimated 3.5 million more malaria cases in 2017 compared 212 million cases reported in 2016. Data from 2015-2017, have shown no significant progress in reducing global malaria cases. In Mainland Tanzania however, malaria control interventions have significantly led to the reduction in malaria prevalence from 18.1% in 2008 to 7.3% in 2017. Despite of these achievements, malaria burden is still highly heterogonous in Tanzania with some regions including urban peripheral areas of Dar es Salaam, presenting persistent malaria over 2%. Study objective: To investigate the factors associated with persistent malaria transmission in urban peripheral areas with a case study of Dar es Salaam. Materials and Methods: This study employed cross – sectional survey to collect data from individual member of the households where 830 individuals were enrolled. A four stage multistage sampling was used to select the study population. Individuals in the households were tested for Malaria infection using malaria rapid diagnostic tests (mRDT), and responded to specific questions. Association between malaria infections and responses to specific questions was measured using Odds ratio. Variables indicated association were included in logistic regression model to determine independent risk factors for persistent malaria transmission in the study areas. Results: Majority of the study participants (58.9%) were female, 55.3% were aged more than 18 years, 82.8% had primary or no education, and 77% were farmers or unemployed. Msongola ward contributed 48.9% of the study participants and the overall malaria prevalence in the study areas was (4.5%). Nets ownership was 17%, usage was 85.8%. The odds of malaria prevalence were 7.76 for individuals who do not own nets (p = 0.001), 5.08 for individuals residing in the households surrounded by mosquito breeding sites (p = 0.006) and 1.21 for individuals residing in houses with unscreened windows (p = 0.001). Conclusion: Low nets ownership, residing in households surrounded by mosquito breeding sites and in households with unscreened windows were independent factors associated with risk of malaria in the areas. Promotion of ITNs coverage, application of biolarvicides through community engagement and house screening will reduce the risk of malaria infection in the areas.