Ebola Reaches Mambasa Territory — Islamic State-Controlled Zone Where Health Workers Cannot Enter

The 2026 Bundibugyo Ebola outbreak has spread into Mambasa Territory in Ituri Province — an area under the control of Islamic State–affiliated armed groups (IS-GRANDE/ADF-allied factions) where health workers are unable to travel, according to reporting by the Center for Infectious Disease Research and Policy (CIDRAP). The development represents a critical escalation in the geographic complexity of the outbreak. Key implications: (1) Mambasa Territory lies adjacent to Irumu Territory (already an active outbreak zone with 31+ confirmed cases) in southern Ituri, on the key corridor between Bunia and Beni. (2) Health workers — including WHO, MSF, and DRC MoH response teams — do not travel to Mambasa due to the active armed group presence, making direct case confirmation, contact tracing, and isolation of patients impossible. (3) The outbreak now simultaneously faces an inaccessibility crisis in northern Ituri (Djugu Territory — armed Lendu militia activity) and complete access denial in southern Ituri (Mambasa — IS-affiliated faction control), creating a pincer of inaccessibility around the heart of the outbreak zone. (4) DRC health authorities have confirmed cases reached Mambasa through community movement along bush tracks and secondary roads not monitored by response teams. (5) WHO AFRO has classified the Mambasa zone as a 'contact tracing dead zone' pending security negotiations. This geographic spread, combined with the existing 23% overall inaccessibility in Ituri, further weakens the already critically low ~45% DRC contact tracing coverage and substantially increases the risk that undetected transmission chains will generate future confirmed clusters in previously unaffected health zones.