It was “the perfect storm”—a tempest that may happen only once in a century—a nor’easter created by so rare a combination of factors that it could not possibly have been worse. Creating waves ten stories high and winds of 120 miles an hour, the storm whipped the sea to inconceivable levels few people on Earth have ever witnessed.
The Perfect Storm: A True Story of Men Against the Sea
A transcendent moment nears upon the world for a microbial perfect storm. Unlike the meteorological perfect storm—happening just once in a century—the microbial perfect storm will be a recurrent event. The two events share a common feature; a combination of factors is the driving force behind each.
The increasingly interconnected and fast-paced world of transcontinental commerce and international travel has made any nation susceptible to the infectious diseases that occur incessantly outside its borders. Infectious diseases today ignore geographic and political boundaries, and thus constitute a global threat that puts every nation and every person at risk. Food products, livestock, exotic pets, and material goods—and the microbes they may carry—are exchanged as cultures from every region of the world are explored. Individuals travel to the other side of the planet in less time than it takes to manifest symptoms of disease, potentially infecting anyone they encounter along their route. Others migrate to escape the perils of war, living in poverty, and under conditions of poor sanitation, creating environ-
ments ripe for the emergence of infectious diseases. Land development for housing or use in agriculture; the creation of dams and reservoirs necessary to maintain water for agricultural use and public consumption; and outdoor recreational activities all bring humans into contact with arthropod vectors, rodents, and other animals capable of transmitting infections. Furthermore, changing climate and weather, as well as natural disasters such as floods and earthquakes, can impact on ecosystems to generate ideal conditions for the transmission of pathogens. The convergence of any number of such factors can create an environment that allows infectious diseases to emerge and become rooted in society.
Whereas the angry sea dissipates to an eventual calm, leaving few witnesses to a meteorological perfect storm, the factors creating a microbial perfect storm can perpetuate and even accelerate its effects—leaving multitudes of people to bear witness and fall victim to its destructive forces. In just two decades, for example, the world has witnessed widespread devastation due to the human immunodeficiency virus (HIV), a pathogen unrecognized before 1981. By 2001, more than 40 million people were estimated to be living with HIV, and 20 million had already died from acquired immunodeficiency syndrome (AIDS), the result of HIV infection.
In 1999, West Nile virus was isolated for the first time in the Western Hemisphere. The infection began with an epicenter in New York; by 2002, nearly 4,000 cases of West Nile encephalitis had been reported in 39 states and the District of Columbia, of which 254 were fatal. Although the first case of West Nile encephalitis was identified in Uganda in 1937, the virus was not considered to be a significant human pathogen because most infections were either mild or asymptomatic. Between 1996 and 1999, however, three major epidemics in urban areas (southern Romania, the Volga region of southern Russia, and the northeastern United States) resulted in hundreds of cases of severe neurological disease and fatal infection from West Nile virus, suggesting a change in the pathogen’s virulence.
In 2001, 22 people in the United States contracted anthrax as innocent victims of an act of bioterrorism. Of these 22, 11 suffered from inhalational anthrax, the most lethal form of disease caused by Bacillus anthracis; 5 deaths resulted. This intentional use of a microbe to cause harm was the sobering realization of a once hypothetical factor in the emergence of a microbial threat. While the anthrax event may be more analogous to artifactual seeding of the clouds, HIV and West Nile virus have emerged as a result of microbial perfect storms—and now continue as turbulent microbial threats to health.
An infectious disease epidemic can be a major destabilizing force for any nation, and endemic infectious diseases sap strength from the population and impede national development. The economic and social instability that typically accompanies or follows in the wake of an infectious disease
outbreak, including an intentional biological attack, can undermine national and international security (National Intelligence Council, 2000). Only very recently has the impact of major infectious diseases on global economic health become a central topic for discussion among world leaders, resulting in significant investments of global resources by the United Nations and major industrial nations. Although numerous infectious diseases— such as tuberculosis, malaria, cholera, plague, and infections with drug-resistant pathogens—have been major destabilizing forces (Chukwuani, 1999; Eandi and Zara, 1998), none has had a more devastating and far-reaching impact than the HIV pandemic in sub-Saharan Africa. The 28.5 million people infected with HIV in the region (UNAIDS, 2002) affect all sectors of society—from the household to industry to the broader regional economy (Dixon et al., 2002; Morris et al., 2000; Topouzis and du Guerny, 1999). With its disproportionate impact on young working adults, the pandemic has greatly intensified labor shortages, leading to catastrophic socioeconomic decline in the regions of highest incidence (Baier, 1997). It is expected that by 2010, per capita gross domestic product (GDP) in some of the hardest-hit countries will drop by 8 percent (UNAIDS and WHO, 2001); heavily affected countries could lose more than 20 percent of GDP by 2010. Decreased productivity translates into weaker prospects for economic growth and long-term development, and also means that fewer resources are available to invest in public health, thereby amplifying and perpetuating the original disease problem. The global security threat from AIDS will only increase as other densely populated nations, such as India and China, continue to struggle with the pandemic.
This report is the successor to a 1992 Institute of Medicine report, Emerging Infections: Microbial Threats to Health in the United States, that first examined the impact of new and reemerging infectious diseases on the United States. Ten years later, the impact of the global burden of infectious diseases on the United States has only increased. Infectious diseases unknown in this country just a decade ago, such as West Nile encephalitis and hantavirus pulmonary syndrome, have emerged to kill hundreds of Americans—and the long-term consequences for survivors of the initial illnesses are as yet unknown. Other known diseases, including measles, multidrug-resistant tuberculosis, and even malaria, have been imported and transmitted within the United States in the last 10 years. Moreover, gains made against sexually transmitted diseases have slowed or reversed in certain population groups. Compounding the threat posed by these infectious diseases is the continuing increase in antimicrobial resistance, which has become pervasive not only in the United States, but worldwide. Further exacerbating the situation is the fact that, despite the link between public health investment and infectious disease control, the United States has diminished its public health capacity to recognize and respond to infectious disease
threats—particularly those originating at the global rather than the national level.
The Committee on Emerging Microbial Threats to Health in the 21st Century was charged to identify, review, and assess the current state of knowledge pertaining to the factors in emerging infectious diseases; to assess the capacity of the United States to respond to emerging microbial threats to health; and to identify potential challenges and opportunities for domestic and international public health actions to strengthen the detection and prevention of, and response to, emerging microbial threats. The scope of this report is limited to infectious diseases that have a direct effect on human health. The committee acknowledges that infectious diseases in animals and agriculture can have indirect effects on human health (e.g., reductions in available food sources, economic and psychological hardships in food animal producers due to culling), but limited the scope of the study for practical purposes. The committee’s recommendations are focused on the most urgent and critical issues that need to be addressed immediately if we are to prevent and control microbial threats to human health.
Chapter 2 examines the magnitude of the problem and reviews the spectrum of microbial threats to health. Chapter 3 sets forth the major factors involved in the emergence of a microbial threat and presents a model and case example to illustrate how the complex convergence of these factors can lead to epidemics of disease. Chapter 4 presents the committee’s conclusions and recommendations for improving the U.S. response to infectious agents that threaten not only the health of its citizens, but also the economy, security, and well-being of the world’s population.
The primary aim of this report, therefore, is to extend understanding of the factors involved in the emergence of infectious diseases and of the global context in which this emergence occurs. Containing future epidemics of infectious disease will require that we recognize and respond to microbial threats whenever, and wherever, they occur.