Background: Severe Plasmodium falciparum malaria remains a major cause of paediatric morbidity and mortality in sub-Saharan Africa and frequently occurs in association with other infections. Data on microbiologically documented co-infections and their clinical impact remain scarce in Central Africa, particularly in Gabon.

Methods: We conducted a retrospective, analytical, hospital-based study of children (<17 years) hospitalised with microscopically confirmed severe malaria at a tertiary referral hospital in Libreville, Gabon, between January 2021 and July 2022. Sociodemographic characteristics, consultation delay, vaccination status, documented co-infections, and clinical outcomes were analysed. Comparisons between isolated severe malaria and malaria with co-infection were performed using univariate analyses.

Results: Among 480 children included, 101 (21.0%) presented with at least one documented co-infection. Co-infected children were younger than those with isolated severe malaria (median age: 3.0 vs 5.0 years; p = 0.049), and children under five years had higher odds of co-infection (OR 1.76, 95% CI 1.12–2.76). Co-infection was most frequent among children aged 37–59 months (25.8%) and infants under one year (20.0%). Respiratory infections were the most common co-infections (43.6%), followed by ENT infections (22.8%) and bacteraemia (14.9%). There a trend towards delayed health-seeking behaviour among co-infected children (p=0.054). Co-infected children experienced longer hospital stays (median: 5.0 vs 4.0 days; p < 0.001), while in-hospital mortality was low and limited to children with isolated severe malaria (0.8%).

Conclusions: Co-infections are common among Gabonese children hospitalised with severe malaria, particularly in younger age groups, and are associated with a trend towards delayed presentation and prolonged hospitalisation, underscoring the need for integrated syndromic management approaches.