Association between malaria and nutrition in Rwanda

Abstract

Undernutrition and malaria remain major global public health concerns, particularly in low and middle-income countries. Both concerns have consistently remained one of the leading causes of morbidity and mortality, particularly in sub Saharan Africa, for decades. Malaria infection and outcomes are partly influenced by host immune responses, which are themselves shaped by various factors. In recent years, the status in certain nutrients, specifically micronutrients and macronutrients, has been increasingly recognized for its role in modulating immune function. Malnutrition, specifically, has been demonstrated to compromise immunological responses and affect susceptibility to malaria. Although nutrient composition is influenced by geographic location, and dietary practices, a significant gap persists in understanding how nutrient intake, assessed through food consumption rather than biochemical markers, influences malaria in Rwanda. Comprehensive Nutrient Gap Assessment and evaluations of biofortified food consumption have provided valuable insights into dietary nutrient gaps in Rwanda, however any study directly investigated the association between food-based nutrient intake and malaria outcomes. Therefore, our project comprised two studies aimed at examining malaria and nutrient intake relationships while accounting for multiple confounding factors in the Rwandan context. The first study explored the relationship between nutritional status and asymptomatic malaria among children under five years of age in Rwanda, a topic that has received limited attention in local research. Using Demographic and Health Survey (DHS) data and applying both unadjusted and adjusted odds ratios, the analysis identified stunting, underweight, and low household wealth index as significant risk factors for asymptomatic malaria. These results highlight the urgent need for integrated strategies targeting both nutrition and malaria prevention in young children living in endemic areas. Furthermore, the study emphasizes the importance of exploring children's actual dietary intake to better understand how nutrient consumption influences malaria risk and outcomes. The second study, a case-control study, investigated the relationship between malaria incidence and nutritional status, with a particular focus on stunting and dietary intake across nine malaria-endemic districts in Rwanda. Data were collected in two phases from November 2021 to September 2022 and from May to December 2023 across all four provinces and Kigali City. Using regression models and odds ratios, the study assessed associations between malaria, macronutrient and micronutrient intake, and stunting. Results revealed that dietary patterns were heavily dominated by starchy staples (56.7%), which, while rich in macronutrients, lacked essential micronutrients. Consequently, there was a high prevalence of micronutrient deficiencies in the studied population, including vitamin A (80.4%), vitamin B2 (76.3%), vitamin B12 (76.7%), calcium (82.5%), zinc (71.7%), and selenium (54.4%). Unadjusted analysis showed significant associations between selenium and vitamin E intake and malaria infection. After adjusting for covariates, deficiencies in vitamin E and iron were positively associated with higher odds of malaria, while increasing age, female sex, and selenium deficiency were linked to reduced odds ratio for malaria infection. The overall study supported that deficiencies in vitamin E, iron, and selenium are linked to either higher or lower risk of malaria infection, highlighting the critical role of nutrition in malaria outcomes. To reduce this risk, there is a need for targeted actions that promote diverse diets, routine assessment of nutritional status, and the development of a national food composition table to guide effective nutrition policies and interventions. Key words: Malaria Nutrition nutritional status asymptomatic malaria RDHS micronutrients malnutrition in children under five cross sectional study case control Rwanda