Malaria Associated Risk Factors Among Adolescent Living in Areas With Persisting Transmission in Senegal: a Case Control Study.

Abstract Background: In Senegal, malaria morbidity has shapely felt down over these past years. However, malaria epidemiology remains heterogeneous with persisting transmission in the southeastern part of the country and more important number of cases arising among older children and adolescents. Little is known about factors associated with clinical malaria among this group. A better understanding of malaria transmission among this new vulnerable group will guide future interventions targeting these key populations. This study aimed to identify factors associated with clinical malaria among adolescents in Senegal. Methods: A case control study was conducted from November to December 2020 in four health posts located in Saraya district. Cases were defined as adolescents (10-19 years) with uncomplicated malaria episode with fever (Temperature>37.5°) or history of fever and a positive malaria RDT. Controls were from the same age group, living in the neighborhood of the case, presenting a negative RDT. A standardized, pre-tested questionnaire was administered to each participant followed by home visit to assess participant’s living conditions. Factors associated with clinical malaria was assessed using a Stepwise Logistic regression analysis.Results: In total, 492 individuals were recruited (246 cases and 246 controls). In a multivariate analysis, factors associated with clinical malaria included non-use of bed net (aOR=2.65; 95% CI =1.58 - 4.45), non-use of other preventive measures (aOR=2.51; 95% CI=1.53 - 4.11) and indoor sleeping (aOR=3.22; 95%CI =1.66- 6.23). Protective factors included age of 15-19 years (aOR=0.38; 95% CI 0.23 - 0.62), absence of stagnant water around the house (aOR=0.27; 95% CI=0.16 - 0.44), having a female as head of household (aOR=0.47; 95% CI=0.25 - 0.90), occupation such as apprentice (OR=0.24; 95%CI=0.11 - 0.52).Conclusions: The study revealed that environmental factors and non-use of malaria preventive measures are the main determinant of malaria transmission among adolescents living in areas with persisting malaria transmission in Senegal. Strategies aiming at improving disease awareness and access to health care interventions such as LLIN are thus needed to improve malaria control and prevention among these vulnerable groups.