Background:ingestion of contaminated water or food is a major contributor to childhood diarrhea in developing countries. In vietnam, the use of community-based information, education and communication (iec) activities could be a sustainable strategy to improve food hygiene and food safety behaviors. This study thus examined the long-term impact of community-based iec activities on food hygiene and food safety behaviors.Methods:in this longitudinal study, we interviewed caregivers of children aged between six months and four years in suburban hanoi. Baseline data were collected in january 2006 (n = 125). After conducting iec interventions, we collected a 1st set of evaluation data in january 2007 (n = 132). To examine the long-term impact of the interventions, we then collected a 2nd set of evaluation data in january 2008 (n = 185). Changes in childhood diarrhea prevalence, iec coverage, and food hygiene and food safety behaviors were assessed over a two-year period using bivariate and logistic regression analyses. Effective iec channels were determined through multiple linear regression analysis.Results:childhood diarrhea was significantly reduced from 21.6% At baseline to 7.6% At the 1st post-intervention evaluation (p = 0.002), And to 5.9% At the 2nd evaluation. Among 17 food hygiene and food safety behaviors measured, a total of 11 behaviors were improved or maintained by the 2nd evaluation. Handwashing after toilet use was significantly improved at both evaluation points. Overall, 3 food safety behaviors and 7 food hygiene behaviors were found to have significantly improved at the 1st and at the 2nd evaluations, respectively. Flip chart communication administered by community groups was identified to be the most effective iec channel for effecting behavior change (p = 0.018).Conclusions:flip chart communication administered by community groups is effective for improving multiple food hygiene and food safety behaviors in sustainable ways, and should be included in water and health promotion programs. 2013 Takanashi et al.