Launched in 2002 in response to inadequate communications during the anthrax attacks and in preparations to the threats posed by H5N1, the Centers for Disease Control and Prevention (CDC)’s Crisis and Emergency Risk Communication (CERC) framework provides health professionals with trainings, tools, and resources to help them communicate effectively during emergencies and public health crises. Since that time, the framework has been used by the organization during outbreaks of infectious diseases. A core argument of CERC is that lack of certainty, efficacy, and trust serve as barriers to compliance with and support in CDC during an outbreak. According to CERC, providing the public with information about health and social risks, as well as information about ways individuals and organizations may ameliorate threats, could counter these perceptions, improve communications, and eventually save lives. However, the dissemination of the organization’s crisis messages depends largely on the mass media coverage. Understanding the news media’s agenda, priorities and role during outbreaks is essential for improving the cooperation between CDC and journalists. However, CERC provides little information about the actual behavior of journalists during crises, as reflected in news coverage of past outbreaks. This work aims to fill that gap in our understanding of the routinization of news during epidemics and its impact on audiences by systematically analyzing the coverage of epidemics in leading newspapers and using experiments to test its effects. This study analyzed 5,006 articles from leading American newspapers covering three epidemics: H1N1, Ebola, and Zika. Using a mixed method of automated and manual content analysis, it identified three distinct themes used to cover the diseases; pandemic, scientific, and social. Next, manual content analysis was conducted to assess the prevalence of information components theorized by CERC to increase certainty, efficacy and trust- information about medical/health risks, social/economic disruptions, and potential individual and organizational responses to ameliorate risks and reduce harm. Analysis of the themes based on CERC principles demonstrated substantial discrepancies between what CDC aims to communicate during epidemics and what the media actually disseminated to the public. An experiment (n = 321) found that exposure to articles representing the themes affected perceptions of certainty, efficacy, and trust, that in turn were associated with intentions to comply with CDC. The experiment also demonstrated the ability of coverage that follows CERC principles more closely to reduce harmful perceptions that were associated with behavioral intentions in target audiences. Implications for public health organizations and communicators are discussed, including ways to improve cooperation with journalists and the use of alternative direct-channels for filling gaps in news media coverage.