NIE 99-17D, January 2000
The Estimate was produced under the auspices of David F. Gordon, National Intelligence Officer for Economics and Global Issues. The primary drafters were Lt. Col. (Dr.) Don Noah of the Armed Forces Medical Intelligence Center and George Fidas of the NIC. The Estimate also benefited from a conference on infectious diseases held jointly with the State Department's Bureau of Intelligence and Research, and was reviewed by several prominent epidemiologists and other health experts in and outside the US Government. We hope that it will further inform the debate about this important subject.
John C. Gannon
Chairman, National Intelligence Council
The Global Infectious Disease Threat and Its Implications for the United States
I am pleased to share with you this unclassified version of a new National Intelligence Estimate on the reemergence of the threat from infectious diseases worldwide and its implications for the United States.
This report represents an important initiative on the part of the Intelligence Community to consider the national security dimension of a nontraditional threat. It responds to a growing concern by senior US leaders about the implications--in terms of health, economics, and national security--of the growing global infectious disease threat. The dramatic increase in drug-resistant microbes, combined with the lag in development of new antibiotics, the rise of megacities with severe health care deficiencies, environmental degradation, and the growing ease and frequency of cross-border movements of people and produce have greatly facilitated the spread of infectious diseases.
In June 1996, President Clinton issued a Presidential Decision Directive calling for a more focused US policy on infectious diseases. The State Department's Strategic Plan for International Affairs lists protecting human health and reducing the spread of infectious diseases as US strategic goals, and Secretary Albright in December 1999 announced the second of two major U.S. initiatives to combat HIV/AIDS. The unprecedented UN Security Council session devoted exclusively to the threat to Africa from HIV/AIDS in January 2000 is a measure of the international community's concern about the infectious disease threat.
As part of this new US Government effort, the National Intelligence Council produced this National Intelligence Estimate. It examines the most lethal diseases globally and by region; develops alternative scenarios about their future course; examines national and international capacities to deal with them; and assesses their national and global social, economic, political, and security impact. It then assesses the infectious disease threat from international sources to the United States; to US military personnel overseas; and to regions in which the United States has or may develop significant equities.
The Global Infectious Disease Threat and Its Implications for the United States
New and reemerging infectious diseases will pose a rising global health threat and will complicate US and global security over the next 20 years. These diseases will endanger US citizens at home and abroad, threaten US armed forces deployed overseas, and exacerbate social and political instability in key countries and regions in which the United States has significant interests.Infectious diseases are a leading cause of death, accounting for a quarter to a third of the estimated 54 million deaths worldwide in 1998. The spread of infectious diseases results as much from changes in human behavior--including lifestyles and land use patterns, increased trade and travel, and inappropriate use of antibiotic drugs--as from mutations in pathogens.
- Twenty well-known diseases--including tuberculosis (TB), malaria, and cholera--have reemerged or spread geographically since 1973, often in more virulent and drug-resistant forms.
Impact Within the United StatesAlthough the infectious disease threat in the United States remains relatively modest as compared to that of noninfectious diseases, the trend is up. Annual infectious disease-related death rates in the United States have nearly doubled to some 170,000 annually after reaching an historic low in 1980. Many infectious diseases--most recently, the West Nile virus--originate outside US borders and are introduced by international travelers, immigrants, returning US military personnel, or imported animals and foodstuffs. In the opinion of the US Institute of Medicine, the next major infectious disease threat to the United States may be, like HIV, a previously unrecognized pathogen. Barring that, the most dangerous known infectious diseases likely to threaten the United States over the next two decades will be HIV/AIDS, hepatitis C, TB, and new, more lethal variants of influenza. Hospital-acquired infections and foodborne illnesses also will pose a threat.
- Although multidrug therapies have cut HIV/AIDS deaths by two-thirds to 17,000 annually since 1995, emerging microbial resistance to such drugs and continued new infections will sustain the threat.
Regional TrendsDeveloping and former communist countries will continue to experience the greatest impact from infectious diseases--because of malnutrition, poor sanitation, poor water quality, and inadequate health care--but developed countries also will be affected:
- Sub-Saharan Africa --accounting for nearly half of infectious disease deaths globally--will remain the most vulnerable region. The death rates for many diseases, including HIV/AIDS and malaria, exceed those in all other regions. Sub-Saharan Africa's health care capacity--the poorest in the world--will continue to lag.
Development of an effective global surveillance and response system probably is at least a decade or more away, owing to inadequate coordination and funding at the international level and lack of capacity, funds, and commitment in many developing and former communist states. Although overall global health care capacity has improved substantially in recent decades, the gap between rich and poorer countries in the
availability and quality of health care, as illustrated by a typology developed by the Defense Intelligence Agency's Armed Forces Medical Intelligence Center (AFMIC), is widening.
We have examined three plausible scenarios for the course of the infectious disease threat over the next 20 years:
The least likely scenario projects steady progress whereby the aging of global populations and declining fertility rates, socioeconomic advances, and improvements in health care and medical breakthroughs hasten movement toward a "health transition" in which such noninfectious diseases as heart disease and cancer would replace infectious diseases as the overarching global health challenge. We believe this scenario is unlikely primarily because it gives inadequate emphasis to persistent demographic and socioeconomic challenges in the developing countries, to increasing microbial resistance to existing antibiotics, and because related models have already underestimated the force of major killers such as HIV/AIDS, TB, and malaria.
A more pessimistic--and more plausible--scenario projects little or no progress in countering infectious diseases over the duration of this Estimate. Under this scenario, HIV/AIDS reaches catastrophic proportions as the virus spreads throughout the vast populations of India, China, the former Soviet Union, and Latin America, while multidrug treatments encounter microbial resistance and remain prohibitively expensive for developing countries. Multidrug resistant strains of TB, malaria, and other infectious diseases appear at a faster pace than new drugs and vaccines, wreaking havoc on world health. Although more likely than the "steady progress" scenario, we judge that this scenario also is unlikely to prevail because it underestimates the prospects for socioeconomic development, international collaboration, and medical and health care advances to constrain the spread of at least some widespread infectious diseases.
Deterioration, Then Limited Improvement
The most likely scenario, in our view, is one in which the infectious disease threat--particularly from HIV/AIDS--worsens during the first half of our time frame, but decreases fitfully after that, owing to better prevention and control efforts, new drugs and vaccines, and socioeconomic improvements. In the next decade, under this scenario, negative demographic and social conditions in developing countries, such as continued urbanization and poor health care capacity, remain conducive to the spread of infectious diseases; persistent poverty sustains the least developed countries as reservoirs of infection; and microbial resistance continues to increase faster than the pace of new drug and vaccine development. During the subsequent decade, more positive demographic changes such as reduced fertility and aging populations; gradual socioeconomic improvement in most countries; medical advances against childhood and vaccine-preventable killers such as diarrheal diseases, neonatal tetanus, and measles; expanded international surveillance and response systems; and improvements in national health care capacities take hold in all but the least developed countries. Barring the appearance of a deadly and highly infectious new disease, a catastrophic upward lurch by HIV/AIDS, or the release of a highly contagious biological agent capable of rapid and widescale secondary spread, these developments produce at least limited gains against the overall infectious disease threat. However, the remaining group of virulent diseases, led by HIV/AIDS and TB, continue to take a significant toll.
Economic, Social, and Political ImpactThe persistent infectious disease burden is likely to aggravate and, in some cases, may even provoke economic decay, social fragmentation, and political destabilization in the hardest hit countries in the developing and former communist worlds, especially in the worst case scenario outlined above:
- The economic costs of infectious diseases--especially HIV/AIDS and malaria--are already significant, and their increasingly heavy toll on productivity, profitability, and foreign investment will be reflected in growing GDP losses, as well, that could reduce GDP by as much as 20 percent or more by 2010 in some Sub-Saharan African countries, according to recent studies.
The relationship between disease and political instability is indirect but real. A wide-ranging study on the causes of state instability suggests that infant mortality--a good indicator of the overall quality of life--correlates strongly with political instability, particularly in countries that already have achieved a measure of democracy. The severe social and economic impact of infectious diseases is likely to intensify the struggle for political power to control scarce state resources.
Implications for US National SecurityAs a major hub of global travel, immigration, and commerce with wide-ranging interests and a large civilian and military presence overseas, the United States and its equities abroad will remain at risk from infectious diseases.
- Emerging and reemerging infectious diseases, many of which are likely to continue to originate overseas, will continue to kill at least 170,000 Americans annually. Many more could perish in an epidemic of influenza or yet-unknown disease or if there is a substantial decline in the effectiveness of available HIV/AIDS drugs.
Leading Causes of Death, 1998
Patterns of Infectious DiseasesBroad advances in controlling or eradicating a growing number of infectious diseases--such as tuberculosis (TB), malaria, and smallpox--in the decades after the Second World War fueled hopes that the global infectious disease threat would be increasingly manageable. Optimism regarding the battle against infectious diseases peaked in 1978 when the United Nations (UN) member states signed the "Health for All 2000" accord, which predicted that even the poorest nations would undergo a health transition before the millennium, whereby infectious diseases no longer would pose a major danger to human health. As recently as 1996, a World Bank/World Health Organization (WHO)-sponsored study by Christopher J.L. Murray and Alan D. Lopez projected a dramatic reduction in the infectious disease threat. This optimism, however, led to complacency and overlooked the role of such factors as expanded trade and travel and growing microbial resistance to existing antibiotics in the spread of infectious diseases. Today:
- Infectious diseases remain a leading cause of death (see figure 1). Of the estimated 54 million deaths worldwide in 1998, about one-fourth to one-third were due to infectious diseases, most of them in developing countries and among children globally.
Examples of Pathogenic Microbes and the Diseases
They Cause, Identified Since 1973