Chapter 85: Emerging Microbial Threats to Health

INTRODUCTION

Despite great progress in the prevention and management of infectious diseases, microbial threats continue to evolve, proliferate, and result in human infection—the consequence of social and ecologic changes associated with a globalized society. The far-reaching effects of the 2003 outbreak of severe acute respiratory syndrome (SARS) highlight the ability of a previously unrecognized agent to appear unexpectedly, spread rapidly in the absence of diagnostics and effective disease prevention strategies, and cause widespread suffering as well as political, economic, and social turmoil. The emergence of SARS, a single example among many in recent years (Table 85-1), also illustrates the potential dangers of infectious agents and underscores the importance of preparedness for the unexpected. The 100th anniversary of the 1918 Spanish influenza pandemic is a reminder of the devastating impact of influenza and why concerns were raised when a new strain of influenza (H1N1) appeared in 2009. Previously known infectious diseases also continue to present new challenges. Some such as West Nile virus (WNV) infection and Zika virus have recently jumped to new continents, whereas others such as Ebola virus caused illness in urban centers of West Africa in numbers well beyond those that occurred previously. Many established diseases, such as malaria and tuberculosis, continue to exact a high burden, fueled in part by antimicrobial resistance.

In 1992, the Institute of Medicine (IOM) published a report¹ describing the increasing public health challenges posed by new, re-emerging, and drug-resistant infections and calling for improvements in the nation’s public health infrastructure. The report identified six factors underlying infectious disease emergence (Box 85-1) and described their impact on diseases that had emerged in the United States in the previous two decades. In 2003, this report was updated² with expanded emphasis on the global impact of infectious disease threats and the international collaborative response needed to address them. In addition to the six underlying factors outlined in the first report, the new report cited ...