Before revision:  (d) it is more difficult to control the disease with asymptomatic cases. The results provide evidence that mass media should not play down the transmissibility and severity of diseases , so that the public can become aware of the disease as soon as possible .
After revision:  (d) social influence on behavior change can remarkably decrease the epidemic outbreak size. This research indicates that the media and opinion leaders should not understate the transmissibility and severity of diseases , so that the public can become aware of the disease as soon as possible .