The Ebola outbreak in the Democratic Republic of the Congo has killed 3,901 people and infected 8,067 others, according to the country’s health ministry, as shortages of health workers and insecurity hamper efforts to contain the disease.

The figures cover 63 health zones across seven provinces as of September 26. Declared on May 15, the outbreak is caused by the rare Bundibugyo strain, which has no approved vaccine or specific treatment.

The World Health Organization (WHO) warned that the high death toll, particularly among people dying in their communities, reflects delays in detecting infections and accessing medical care.

The UN humanitarian office said routine primary health care services in Ituri province fell 13% between April and June as resources were diverted to the outbreak.

The Africa Centers for Disease Control and Prevention said 50 health workers had died since the outbreak began. Insecurity, displacement and strikes over delayed wages have further complicated containment efforts, even as some areas report fewer cases.