New Delhi, May 26 -- Every time Vanny Birungi, a volunteer with the Red Cross in eastern Congo, goes out to raise awareness about the latest Ebola outbreak as suspected cases near 1,000, she faces a double threat.

One is the rare Bundibugyo type of Ebola, with no vaccine or treatment. The other is the anger and suspicion of residents who have pelted her with stones and verbal abuse in Bunia, a city at the heart of the outbreak.

"We continue to tell them that the disease is out there. Some accept, and others don't," Birungi told The Associated Press on Monday as she and colleagues spoke with groups of people in a working-class neighborhood under the scorching sun.

Aid workers are especially at risk in this volatile region where resident...