Outbreaks of novel influenza viruses are continually occurring on many places on our planet, with the ultimate and most extreme consequence being a full-scale pandemic. Modern communication technology is widely used for risk communication regarding recommended change in behavior patterns and other precautions in order to mitigate the transmission. However, the assumption and bias that modern communication technology constitutes the norm causes vulnerable groups to be at possible risk of systematic exclusion to correct and updated information. Through conducting a literature- and case analysis, the aim of this study is to identify insufficient or inadequate risk communication efforts in South Korea and Vietnam during influenza outbreaks, especially with concern of vulnerable groups. Further, to analyze how national influenza preparedness plans observe or ignore these insufficiencies. Results show that vulnerable groups are explicitly recognized in the preparedness plan of Vietnam. However, the South Korean preparedness plan show a more homogenous approach. Both South Korea and Vietnam showed a broad variety of channels used in their risk communication strategies which could be positive in terms of a broad outreach to a heterogenous population, including vulnerable groups. Four key factors that moderate the outcomes of risk communication were identified: Channels, Messages, Transparency and Trust.