Cluster of community deaths in Basankusu, Equateur- Democratic Republic of the Congo

On 9 February 2025, officials in the Democratic Republic of the Congo reported to regional health authorities a cluster of 24 unexplained community deaths in a single village in Ekoto health area, Basankusu health zone, Equateur province. As of 25 February, a total of 53 deaths have been reported, with the last death occurring on 22 February.

Deaths have occurred in all age groups, but adolescents and young adults, particularly males, appeared to be disproportionately affected in the initial cluster reported. Disease progression appeared to be fast, with a median time from onset of symptoms to death of one day.

Given the rapid decline in the incidence of reported deaths, their geographic clustering, the age profile of deaths and the rapid disease progression in the initial cluster, working hypotheses include chemical poisoning or a rapid onset bacterial meningitis cluster, on a background of malaria and other infectious illnesses endemic in the region. The definitive cause of illness remains undetermined, with initial samples testing negative for Ebola and Marburg viruses.

Field investigations and additional laboratory testing are ongoing including but not limited to the cerebrospinal fluid testing and the toxicological analysis of environmental samples, including water and other samples to explore chemical causes. Local authorities began surveillance with a broad case definition including any individual with fever and at least one other symptom, to better understand disease patterns. A total of 1318 patients had symptoms meeting the working suspected case definition as of 25 February 2025. Approximately 50% of malaria tests performed on these cases tested positive for malaria, the cases identified through this enhanced surveillance therefore likely reflect the various febrile illnesses in the area.

With the available information, WHO assesses the local public health risk as moderate, and the national and global public health risk as low.