The United Nations has probably missed targets it set for curbing West Africa's Ebola epidemic, as new infections surge in Sierra Leone.

Only 23 percent of cases are being isolated in Liberia, and 40 percent in Sierra Leone, short of a goal set in October to isolate 7-in-10 cases by Dec. 1. Neither country has enough burial teams to achieve a target of safely burying 70 percent of Ebola-related deaths, according to the World Health Organization. Still, unreliable data make it difficult to know conclusively whether the goals have been met, the Geneva-based WHO said.

While new infections are declining in Liberia and holding steady in Guinea, they're rising in Sierra Leone, particularly in the country's north and west, including the capital Freetown, according to the WHO. Burial rites in which mourners touch the corpse of a dead person are continuing to contribute to the spread of Ebola in Sierra Leone, Alpha Kanu, the nation's information minister, said in a Nov. 27 briefing.