Abstract
<title>Abstract</title> <p> <bold>Background:</bold> Severe <italic>Plasmodium falciparum</italic> malaria remains a leading cause of paediatric morbidity and mortality in sub-Saharan Africa, recent data from urban Republic of the Congo are scarce. This study assessed the frequency, clinico-biological profile, risk factors and in-hospital death of severe malaria among children admitted to referral hospitals in Brazzaville. <bold>Methods:</bold> This prospective, multicentre cross-sectional study (January–December 2024) analyzed children under 15 hospitalized with confirmed <italic>P. falciparum</italic> malaria in Brazzaville. Using 2014 WHO criteria, determinants of severe malaria and in-hospital mortality were identified via multivariable logistic regression. <bold>Results:</bold> Of 1,050 children screened, 441 were eligible and included; severe malaria accounted for 161 (36.5%) cases and moderate malaria for 280 (63.5%). The median age was 48.0 months (IQR 15.0-96.0), and 240 children (54.4%) were younger than five years. In-hospital mortality was 7.0% (31/441) in the overall cohort and 18.0% (29/161) in the severe malaria group, compared with 0.7% (2/280) in the moderate malaria group ( <italic>p<</italic> 0.001). The predominant WHO 2014 features in the severe malaria group were composite neurological involvement (62.7%), severe anaemia (40.4%), repeated convulsions (39.1%) and coma (37.9%). The case fatality rate rose with the number of concurrent WHO criteria, from 14.5% with a single criterion to 44.4% with four or more criteria. Independent determinants of severe malaria were pre-hospital antimalarial self-medication (aOR 3.00; 95% CI 1.75-5.16; <italic>p<</italic> 0.001) and delayed consultation beyond 48 hours (aOR 2.16; 95% CI 1.28-3.63; <italic>p</italic> =0.004). Independent risk factors for in-hospital death were severe malaria status (aOR 12.33; 95% CI 2.50-60.78; <italic>p</italic> =0.002), acute kidney injury (aOR 5.96; 95% CI 1.47-24.11; <italic>p</italic> =0.012) and age<5 years (aOR 2.98; 95% CI 1.12-7.91; <italic>p</italic> =0.029). <bold>Conclusions:</bold> Severe paediatric malaria carries substantial mortality in Brazzaville, independently driven by acute k and age under five years. Pre-hospital self-medication and delayed consultation were the principal modifiable determinants of severe disease. Reducing these behavioural delays and ensuring access to paediatric renal support should be prioritised in the national malaria control strategy. </p>