The move highlights the complexity of tackling Ebola amid ongoing hostilities between the Congolese government and the rebels.
The M23 alliance, which captured Goma and Bukavu in early 2025, has sought to demonstrate its administrative capacity by mounting a parallel Ebola response in territories under its control.
In late June, the rebel authorities declared their zones Ebola-free.
Ebola is a rare but deadly viral disease and the Bundibugyo species is even rarer, with only two known prior outbreaks.
Symptoms of Ebola, which are similar to the flu or malaria, include fever, headache and tiredness, and can begin suddenly within two to 21 days of infection.
As the disease progresses, vomiting and diarrhoea can develop, leading to organ failure. Contact with infected bodily fluids such as blood or vomit causes the virus to spread.