In theory, you can fight HIV/AIDS by teaching safe sexual behavior; fight diarrhea by promoting hygienic practices; reduce child mortality by educating mothers; etc. However:

• Research on the effectiveness of these sorts of programs is thin; and programs that combine documented effectiveness with clear replication models are, so far as we can tell, rare to nonexistent.
• Changing people’s behavior isn’t straightforward. For an example, consider the finding – regarding hygiene education – that “The interventions promoting the single hygiene practice of washing one’s hands with soap tended to achieve greater reductions in disease than those that promoted several different behaviors … numerous messages dilute each other in the minds of the target audience” (see DCP pg 785 – references given there).

If it’s true that education works best when it’s focused, that means that planning an education program right means not just identifying behaviors that need changing, but analyzing which changes would be most beneficial. That’s a complex undertaking, and so is changing how people from another culture live their daily lives.

I’m generally not very optimistic about this category of intervention given what we know about it. Handwashing programs appear to be pretty well-documented and are a possible exception.