Ask HN: What are some ways to educate at-risk groups about hazards?

There are several at-risk populations whose own ignorance, prejudices, and fear is preventing helpful outside intervention. For example, the failure of the government of Liberia to maintain an effective quarantine of Ebola patients due to interference by mobs of protesters. How would an NGO go about calming and teaching the population that the hospitals are not killing the patients? What are some time-tested strategies for rapidly educating large groups of people about hazards?