Unlike traditional macroeconomic analysis on financial crises, this paper investigated the relationship between the effects of propagating negative messages, which leads to deterioration of the economic situation over time. The theory of financial crises generated by the spread of investors’ panic is analogized by an infectious disease model. The basic reproduction number is thereafter calculated to determine the propagation of negative messages in a group of investors, the maximum number of investors that can be influenced by negative messages and the maximum threshold value of influenced investors before a financial crisis occurs. The calculations demonstrated that the number of investors influenced by negative messages when governments publish relevant policies, such as monetary policy, financial policy etc., to prevent financial crises is clearly lower than the number of investors influenced by negative messages when governments take no action. Therefore governments’ interference in financial uncertainty can effectively reduce the possibility of financial crises occurring.
