Rates of bacteremia among children presenting with highland malaria in Vihiga County, Kenya

Malaria remains a major cause of pediatric morbidity and mortality in sub-Saharan Africa. In highland regions like Vihiga County, Kenya, where malaria transmission is unstable, children are especially vulnerable to severe disease and complications. Bacteremia is an increasingly recognized co-infection in children with malaria, yet its burden and clinical profile in highland settings remain poorly characterized. This study aimed to determine the prevalence and distribution of bacterial pathogens among children diagnosed with malaria in Vihiga County and to evaluate the association between sociodemographic and clinical characteristics and the occurrence of bacteremia in this population. A cross-sectional study was conducted among children aged ≤60 months presenting with malaria. Blood samples were collected for malaria microscopy, full blood counts, and aerobic blood cultures. Data on clinical and demographic variables were analyzed using descriptive statistics and logistic regression to determine associations with bacteremia. Out of 312 children with malaria, 34 (10.9%) were bacteremic. The most commonly isolated pathogens were non-typhoidal Salmonella spp. (44.1%), Escherichia coli (23.5%), and Staphylococcus aureus (14.7%). Significant predictors of bacteremia included age below 12 months (Odds Ratio [OR] = 2.3, 95% Confidence Interval [CI]: 1.3–4.1), high-grade fever (OR = 2.2, 95% CI: 1.1–4.0), pallor (OR = 2.8, 95% CI: 1.4–5.3), respiratory distress (OR = 3.4, 95% CI: 1.8–6.4), severe anemia (OR = 2.9, 95% CI: 1.5–5.6), underweight status (OR = 2.1, 95% CI: 1.2–3.5), and hospitalization (OR = 3.6, 95% CI: 2.0–6.2). Bacteremia was associated with significantly longer hospital stays and higher mortality (17.6% vs. 0.4%). The prevalence and pathogen profile of bacteremia in Vihiga County mirror those of other high-burden settings in Africa, with non-typhoidal Salmonella predominating. Clinical predictors identified in this study are consistent with previous literature and highlight the difficulty of clinically distinguishing malaria from co-infection in resource-limited settings. Bacteremia is a common and clinically significant co-infection among children with malaria in Vihiga County. It is associated with severe clinical manifestations and poor outcomes. Routine blood culture diagnostics should be integrated into pediatric malaria care in high-risk areas. Additionally, risk-based clinical screening tools should be implemented to guide early empirical antibiotic treatment for children presenting with malaria and features suggestive of bacteremia.