DR Congo: Ebola Outbreak, Kasai Province Situation Report #1

September 4, 2025

SITUATION UPDATE

On September 1, officials in the Kasai province of the Democratic Republic of the Congo (DRC)—a small, isolated province in the southwest of the country—raised the alarm in response to a case of hemorrhagic fever of unknown origin. Kasai is a province with a history of Ebola virus disease (EVD). Three samples collected from suspected cases were sent by health authorities to the National Institute of Biomedical Research in the DRC’s capital, Kinshasa. By the time officials confirmed the suspected cases were indeed the Zaire strain of EVD, there were already 28 suspected cases and 15 deaths, including four healthcare workers who treated the first Ebola-positive patient.

Ebola Zaire is a highly contagious hemorrhagic-fever virus that halts the body’s blood-clotting system, causing blood to leak from small vessels all over a patient’s body, causing internal bleeding, inflammation, bleeding and loss of fluid. If untreated, the body goes into shock from fluid loss. The Ebola Zaire strain is the strain that killed more than 11,000 people during the West African Ebola outbreak in 2014–2016. Ebola Zaire can result in up to a 90% mortality rate for infected patients, though high-quality healthcare and early diagnosis can help bring this rate down as low as 28%. Multiple treatments and a vaccination have been utilized in recent outbreaks, though risk for transmission prior to vaccination remains high and the treatments available are still new.

Bulape and Mweka health zones in Kasai province, where the cases have surfaced, are extremely isolated. There is very little air travel to this province and the journey from Kinshasa to Kasai can take multiple days via road during the rainy season. Unlike many other regions of the DRC, Kasai is a stable province, though there is chronic food insecurity, leading to cases of severe acute malnutrition, due to poverty and geographic isolation. The health system is weak and underfunded, leaving many community members to seek medical attention from traditional healers. These issues are exacerbated by inter-ethnic conflict leading to occasional population displacement, as well as large-scale issues caused by extreme weather events.