The health care providers who participated in our study emphasized that the widespread of the outbreak requires follow-up and assessment of all influenza cases who applied to health care centers. As the interviewees stated, trace-back investigations were not performed because of the current surveillance system mentioned above. The need for an active surveillance system is clear for an epidemic disease such as avian influenza, which is seasonal, regional and closely related to epidemic diseases related to agricultural practice. In the WHO Report dealing with lessons from the avian influenza outbreak in Turkey, the need for active surveillance of animal and human avian influenza outbreaks was underlined [3] . A well integrated effort such as lining up a network between animal and public health laboratory system is needed to define an epidemic earlier, ensure more effective control measures [7, 15] . This will possibly make us gain valuable time by delaying a pandemic.