A multidisciplinary investigation into a large outbreak of an unknown febrile illness in the Panzi Health Zone of the Democratic Republic of the Congo in late 2024 found that these were largely malaria cases associated with concurrent viral respiratory infections. Between October 24 and December 5, 2024, there were 406 cases with symptoms of fever, headache, cough, runny nose and body aches, with 31 deaths (fatality rate 7.6%). More than 70% of deaths affected people under the age of 15, with children under 5 making up 54.8% of them. Rapid tests on more than 500 samples showed 55.6% positive for malaria, and 77.9% of 70 blood smears were positive. On 17 December 2024, the DRC Ministry of Health announced that it was a severe form of malaria, while the WHO described it as acute respiratory infections complicated by malaria and acute malnutrition. Coordination has been strengthened at national, provincial and community levels, with rapid response teams including WHO experts deployed from 30 November 2024. Cases have occurred in family clusters, suggesting household transmission.