The risk factor analysis indicated that the job that spend less time at home more at risk of DF than the others (OR=2.79, 95% OR: 1.32 - 5.87), no use mosquitoes' essential oil / repellent (OR=2.21, 95% OR: 1.04 - 4.68), the stable near house (OR=4.86, 95% OR: 1.21 - 19.51) were independent risk factors for the development of DF.