Exploring the prevalence and association between nutritional status and asymptomatic malaria in Rwanda among under-5 children: a cross-sectional analysis.

Background: Undernutrition and severe malaria continue to be major public health concerns worldwide, particularly in African countries. While the association between malaria and malnutrition has been widely studied in various settings, limited research has focused on asymptomatic malaria and its link to nutritional status in Rwanda, leaving a gap in understanding this relationship in the local context. This study aimed to investigate the possible relationship between children's nutritional health and asymptomatic malaria infections. Specifically, the study assessed the prevalence of undernutrition and asymptomatic malaria infection in relation to implemented policies and the link between stunting, wasting, underweight, and asymptomatic malaria infections.

Methods: Data from three Demographic and Health Surveys (DHS) conducted in Rwanda in 2010, 2014-15, and 2019-20 were used in the study, including children aged 6 to 59 months and confirmed malaria diagnoses via blood smear. The odds ratio of stunting, underweight, and wasting on malaria outcomes were calculated using logistic regression, with and without adjusting for factors such as age, gender, mother's education, wealth index, type of residence, and region within each survey. The present study examined data from three DHSs conducted in Rwanda, which included 10,411 children aged less than five years who were tested for malaria and 11,424 children who had anthropometric measurements. Despite this variation, the available sample size (n = 10,409) remains robust for drawing meaningful conclusions, and potential biases due to missing data in the analysis were taken into account. This study used unadjusted (OR) and adjusted odds ratios (AOR) to evaluate the relationships between stunting, underweight, age, wealth index, and malaria outcomes. All independent variables with a p-value below 0.05 in the unadjusted regression were included and considered significant in the adjusted regression analysis. A p-value < 0.05 was used to determine statistical significance.

Results: Asymptomatic malaria was found to be present in 1.3% (95% confidence interval (CI) 1.14%-1.59%) of the population (140/10,411). The study also discovered that 38.3% (95% CI 37.42%-39.21%) of the children were stunted (Z-score < - 2.0). Moreover, the results indicate that malaria was more frequent in children with stunting (OR = 1.85, 95% CI = [1.32; 2.59], p < 0.001). Underweight children were also found to have an increased prevalence of malaria (AOR = 1.59, 95% CI [1.14-2.95], p = 0.01). Age was also an important variable correlated with malaria infection since the prevalence of malaria was found to be higher in children over 24 months of age (AOR = 2.72, 95% CI [1.78-4.16], p < 0.001). Children from the richest families were found to be protected from malaria AOR = 0.38 (95% CI [0.24-0.58], p < 0.001) in all 3 DHS.

Conclusion: This study revealed that undernutrition indexes such as stunting and underweight as well as poor wealth index are significant risk factors for asymptomatic malaria in children under the age of five years. Malaria itself can worsen nutrition status, creating a vicious cycle. Monitoring and enhancing this dual relationship of nutritional status and malaria highlights the essential needs of children in this age group in malaria-endemic settings.