BACKGROUNDThe current definition of severe malaria in non-endemic areas follows WHO criteria, which mainly target children in malaria-endemic areas, potentially misclassifying cases in non-endemic regions. We assessed the performance of a modified severe malaria classification criteria within our patient cohort. METHODSA cohort study of patients managed for malaria in a non-endemic setting(2005-2023) was analyzed. We classified patients into severe malaria (SM) using WHO 2013 criteria except for hyperparasitemia, where 2% threshold was applied. Patients with SM were distinguished as very severe malaria(VSM) when presenting at least one of the following conditions: parasitemia >10%, pulmonary edema, impaired consciousness, seizures, renal failure, metabolic acidosis or hyperlactatemia, shock or hypoglycemia. In patients with SM and no criteria for VSM, less severe malaria(LSM) was defined by: 2-10% parasitemia, hyperbilirubinemia, prostration, anemia or minor bleeding. The primary composite outcome was death or the need for a life-saving intervention, as analyzed in the three comparative groups. Secondary outcome was the prevalence of co-infections. RESULTSAmong 506 patients with malaria, 176(34.8%) presented with SM. A total of 37(7.3%) patients developed a life-threatening condition, namely death (n=4) and/or the need for life-saving interventions(n=34). All fatalities and 33 out of the 34 life-saving interventions occurred in the VSM group. Patients in LSM group did not develop any life-threatening conditions. As to co-infections, 28(5.5%) patients had a community-acquired co-infection, with no differences between groups (p=0.763). CONCLUSIONSSeverity criteria definitions would benefit from a review when assessing patients with malaria in non-endemic areas. Within the spectrum of SM, patients reclassified as LSM have a low risk of developing a life-threatening condition and present low co-infection incidence and could benefit from management out of intensive care units and a restrictive use of empirical antibiotics.