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Persons using assistive technology might not be able to fully access information in this file. For assistance, please send e-mail to: mmwrq@cdc.gov. Type 508 Accommodation and the title of the report in the subject line of e-mail. Preventing Emerging Infectious Diseases: A Strategy for the 21st Century Overview of the Updated CDC PlanPathogenic microbes can be resilient, dangerous foes. Although it is impossible to predict their individual emergence in time and place, we can be confident that new microbial diseases will emerge.
Summary Societal, technological, and environmental factors continue to have a dramatic effect on infectious diseases worldwide, facilitating the emergence of new diseases and the reemergence of old ones, sometimes in drug-resistant forms. Modern demographic and ecologic conditions that favor the spread of infectious diseases include rapid population growth; increasing poverty and urban migration; more frequent movement across international boundaries by tourists, workers, immigrants, and refugees; alterations in the habitats of animals and arthropods that transmit disease; increasing numbers of persons with impaired host defenses; and changes in the way that food is processed and distributed. Several recent health events underscore the need for a public health system ready to address whatever disease problems that might arise. For example, in 1997, an avian strain of influenza that had never before infected humans began to kill previously healthy persons in Hong Kong, and strains of Staphylococcus aureus with diminished susceptibility to the antibiotic vancomycin were reported in Japan and the United States. In addition, researchers recently discovered that a strain of the virus that causes acquired immunodeficiency syndrome (AIDS) had been infecting humans for at least 20 years before AIDS emerged as a worldwide epidemic. Preventing Emerging Infectious Diseases: A Strategy for the 21st Century describes CDC's plan to combat today's infectious diseases and prevent those of tomorrow. It represents the second phase of the effort launched in 1994 with the publication of CDC's Addressing Emerging Infectious Disease Threats: A Prevention Strategy for the United States. This overview of the updated plan outlines specific objectives under four major goals: a) surveillance and response, b) applied research, c) infrastructure and training, and d) prevention and control. Achieving these objectives will enhance understanding of infectious diseases and bolster their detection, control, and prevention. The plan also targets nine categories of problems that cause human suffering and place a burden on society. The aim of this plan is to build a stronger, more flexible U.S. public health system that is well-prepared to respond to known disease problems, as well as to address the unexpected, whether it be an influenza pandemic, a disease caused by an unknown organism, or a bioterrorist attack. The implementation of this plan will require the dedicated efforts of many partners, including state and local health departments, other federal agencies, professional societies, universities, research institutes, health-care providers and organizations, the World Health Organization, and many other domestic and international organizations and groups. INTRODUCTION Infectious diseases are a continuing threat to all persons, regardless of age, sex, lifestyle, ethnic background, and socioeconomic status (1). They cause suffering and death and impose a financial burden on society (Table_1) (2-12). Although some diseases have been conquered by modern advances such as antibiotics and vaccines, new ones are constantly emerging (e.g., human immunodeficiency virus and acquired immunodeficiency syndrome {HIV/AIDS}, Lyme disease, and hantavirus pulmonary syndrome), whereas others reemerge in drug-resistant forms (e.g., malaria, tuberculosis, and bacterial pneumonias). Because no one knows what new diseases will emerge, the public health system must be prepared for the unexpected. For example, in 1997, an avian strain of influenza that had never before attacked humans began to kill previously healthy persons in Hong Kong (13). This crisis raised the specter of an influenza pandemic similar to the one that killed 20 million persons in 1918. Also in 1997, strains of Staphylococcus aureus with diminished susceptibility to vancomycin were reported in Japan and the United States (14). If drugs like vancomycin cannot be replaced as they lose their effectiveness -- or if the emergence and spread of drug resistance cannot be limited -- some diseases might become untreatable, as they were in the preantibiotic era. In addition, the recent discovery that a strain of the virus that causes HIV/AIDS has been infecting humans at least since 1959 (15) illustrates how infectious agents can remain undetected for years before emerging as public health problems. Each of these incidents underscores the need for a public health infrastructure that is ready to address whatever disease problems that might arise. Preventing Emerging Infectious Diseases: A Strategy for the
21st Century (16) describes steps that can be taken to move toward
realizing CDC's vision of a world in which individuals,
communities, and nations join in a common effort to combat today's
emerging infectious diseases and prevent those of tomorrow. Copies
of the plan will be available from the Office of Health
Communication, National Center for Infectious Diseases (NCID),
Centers for Disease Control and Prevention, Mail Stop C-14, 1600
Clifton Road, Atlanta, GA 30333. The plan also can be accessed from
the NCID home page at CDC's PLAN TO PREVENT EMERGING INFECTIOUS DISEASES Preventing Emerging Infectious Diseases: A Strategy for the 21st Century represents the second phase of CDC's plan to revitalize the country's capacity to protect the public from infectious diseases, an effort that was launched in 1994 with the publication of Addressing Emerging Infectious Disease Threats: A Prevention Strategy for the United States (17). During the past 4 years, CDC has implemented the 1994 plan incrementally, with the help of many partners. By fiscal year 1997, funds were available to implement about one third of the recommended programs and activities, which focused on improving surveillance, conducting applied research, rebuilding the public health infrastructure, and strengthening efforts to prevent emerging infectious diseases. CDC decided to update its plan in 1998 because of recent developments (see page 4, Events Prompting CDC to Update the 1994 Plan {18-31}) and because of the need to build on achievements from implementing the 1994 plan (see Appendix to the 1998 plan {16}). Preventing Emerging Infectious Diseases: A Strategy for the 21st Century takes into account the new discoveries and challenges of the past 4 years and builds on the experience, accomplishments, and knowledge gained from implementing the 1994 plan. Persons from approximately 50 organizations contributed to the development of the updated plan; they and many other partners will be essential to the plan's implementation. CDC will implement the plan in coordination with state and local health departments (e.g., on surveillance of infectious diseases), academic centers and other federal agencies (e.g., on research agendas), health-care providers and organizations (e.g., on development and dissemination of guidelines), international organizations (e.g., on outbreak responses overseas), and many other partners. Events Prompting CDC to Update the 1994 Plan CDC decided to update its strategy for addressing emerging infectious diseases because of progress in implementing the highest priorities in the 1994 plan as well as several recent developments: Emerging Threats
Scientific Findings
Tools and Technologies
Changes in Health-Care Delivery
Public and Policy Issues
Goals and Objectives The objectives of Preventing Emerging Infectious Diseases: A Strategy for the 21st Century are organized under four goals: surveillance and response, applied research, infrastructure and training, and prevention and control. Under each objective, the plan describes in detail the many public health activities that must be conducted to implement CDC's strategy. Goal I -- Surveillance and Response. Detect, investigate, and monitor emerging pathogens, the diseases they cause, and the factors influencing their emergence, and respond to problems as they are identified. Objectives
The objectives and activities of Goal I reflect recent changes in needs and capabilities for surveillance and response. For instance, outbreaks of foodborne illness used to be primarily local events that were easily recognized. Now, however, outbreaks often involve persons scattered over wide geographic areas -- the consequence of regional, national, or international distribution of food products. In recent years, through various coordinated efforts including the 1997 National Food Safety Initiative, the U.S. Food and Drug Administration, U.S. Department of Agriculture, CDC, and other agencies have begun to enhance national capacity to track and respond to foodborne illnesses across the country. In mid-1998, the Secretary of Health and Human Services announced PulseNet -- a national network of laboratories that perform DNA fingerprinting of bacteria isolated from patients and contaminated food. The network permits rapid comparison of molecular fingerprint patterns through an electronic database at CDC. When patterns submitted from different sites are identical, the computer alerts health agencies to a possible widespread outbreak of foodborne illness (Figure_1B) (see page 7, Pulsed-Field Gel Electrophoresis Patterns of Escherichia coli O157:H7 Isolates -- Washington State, 1996). During the next several years, CDC will continue to develop PulseNet in partnership with state health departments and the Association of Public Health Laboratories, increasing the number of participating laboratories and the number of organisms covered. PulseNet demonstrates how CDC and its partners can use modern laboratory techniques and electronic communications to strengthen disease surveillance and response. The objectives and activities described under Goal I address the need for a strong and coordinated system for surveillance and response in the United States and abroad, not only for foodborne diseases but for other emerging infectious diseases as well. They call for increased links among surveillance sites, improved tools and approaches for conducting surveillance, as well as prompt and effective translation of surveillance data into public health action. Goal II -- Applied Research. Integrate laboratory science and epidemiology to optimize public health practice. Objectives
Research is essential in efforts to understand, prevent, control, and respond to new and reemerging infectious diseases. Much of CDC's emerging infectious disease research is laboratory-based or epidemiologic, often performed in response to an emergency such as an outbreak of disease. In addition, CDC conducts studies in nonoutbreak settings to evaluate prevention strategies and identify factors that put persons at increased risk. For example, between 1993 and 1995, in partnership with several other organizations, CDC conducted Project Respect -- a randomized trial of alternative approaches to counseling persons who visit medical clinics about how to prevent HIV and other sexually transmitted diseases (STDs). One group received simple educational messages, and the other received intensive counseling that focused on the client's personal situation. After 6 months, persons who received client-centered counseling were substantially more likely to use condoms 100% of the time and had substantially fewer new STDs (32). At 12 months, rates of condom use were similar in the two groups, but the reduced rate of new STDs persisted among persons who received client-centered counseling. CDC and other Project Respect investigators are translating these research findings into prevention programs that can be delivered in other clinical settings. Project Respect is an example of the type of prevention research efforts that will be conducted under Goal II. Goal III -- Infrastructure and Training. Strengthen public health infrastructures to support surveillance and research and to implement prevention and control programs. Objectives
The public health infrastructure is the underlying foundation that supports the planning, delivery, and evaluation of public health activities and practices. For example, a strong public health infrastructure is needed to ensure that the public is safe from vaccine-preventable diseases like polio, measles, and diphtheria, as well as rubella, an acute viral infection that can cause severe birth defects in babies born to infected mothers. Although no major epidemics of childhood rubella have occurred in the United States since the introduction of rubella vaccine in 1969 (33), rubella cases have increased recently among adults, particularly among persons who come from countries without rubella vaccination programs (34). This increase places susceptible pregnant women and their fetuses at risk (34). The North Carolina Department of Environment, Health, and Natural Resources' handling of a 1997 rubella outbreak exemplifies the kinds of activities called for under Goal III. The outbreak, which affected nine of the state's counties, occurred shortly after a rubella surveillance system had been established, and the outbreak was detected early. Health workers visited the homes and workplaces of infected persons and vaccinated friends of patients, family members, and fellow employees. Pregnant women who potentially were exposed received medical follow-up. The outbreak was contained, and no cases of congenital rubella syndrome were reported. North Carolina's rubella surveillance system was established with funding from CDC, which since 1994 has provided grants to state and large city health departments for establishing systems to monitor and track vaccine-preventable diseases. The objectives and activities described under Goal III will help ensure that in future years state and local health departments have the equipment, staff, and training to respond to emerging infectious disease threats in the Untied States, whether they be outbreaks of rubella, drug-resistant microbes, or acts of bioterrorism. Because microbes can cover wide geographic areas and span borders between nations, the objectives and activities of Goal III also address the need to help build global infrastructure to combat emerging infectious diseases. Goal IV -- Prevention and Control. Ensure prompt implementation of prevention strategies and enhance communication of public health information about emerging diseases. Objectives
All of the goals and objectives in this plan ultimately are directed at preventing and controlling infectious diseases. For example, a national effort to prevent the transmission of group B streptococcal infection to newborns is based on ongoing disease surveillance (Goal I), multidisciplinary research (Goal II), and strong local public health infrastructures (Goal III). One of five women carries group B streptococcal bacteria, although the infections are usually asymptomatic (35,36). When transmitted from an infected pregnant woman to her newborn during childbirth, however, the bacteria can cause severe health problems for the baby and even result in death (37). Although studies in the 1980s documented that administering antibiotics during childbirth to women at high risk could prevent group B streptococcal infection in newborns (36), a study completed in 1990 determined that thousands of U.S. babies continued to be infected each year, primarily because antibiotics were not always administered when needed (37). CDC has responded to this problem by working with public and private organizations to develop and distribute new recommendations for disease prevention (36). Between 1993 and 1995, as obstetricians adopted the new policies, the incidence of neonatal group B streptococcal infections declined by as much as 43% in some areas (38) and continued to decline through 1997 (personal communication, Anne Schuchat, M.D., CDC, 1998). CDC is continuing to work with community groups, health departments, and professional organizations to bring standardized prevention protocols to a wider audience (39). As demonstrated by this example, preventing and controlling emerging infectious diseases requires the combined and coordinated work of many persons and organizations. The objectives and activities in Goal IV emphasize the need for strong partner- ships to address emerging infectious disease problems. Target Areas To accomplish these goals, objectives, and activities, Preventing Emerging Infectious Diseases: A Strategy for the 21st Century targets nine categories of problems that cause human suffering and place a burden on society:
ANTICIPATED OUTCOMES Achievement of the objectives described in this plan will improve understanding of infectious diseases and bolster their detection, control, and prevention. The goal of this plan is a stronger, more flexible U.S. public health system that is well prepared to respond to known disease problems and to address the emergence of new infectious pathogens. Implementation of this plan will produce the following results:
References
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Table_1 TABLE 1. Annual national costs and charges* associated with some infectious diseases -- United States, selected years (1991-1993) ======================================================================================================== Disease Annual cost Type of cost -------------------------------------------------------------------------------------------------------- Acquired immunodeficiency syndrome $5.8 billion Direct medical charges (1993 dollars) (2 ) Tuberculosis (3 ) $703 million Direct medical charges (1991 dollars) Nosocomial infections (acquired in $4.5 billion Hospital charges (1992 dollars) hospital) (4 ) Foodborne bacteria (5 ) $2.9-$6.7 billion+ Direct and indirect costs (1993 dollars) Human papillomavirus (6-10 ) $1.23 billion& Direct medical charges (1991 dollars) Neonatal group B streptococcal $294 million Direct medical charges (1993 dollars) infections (11 ) Bacterial vaginosis (12 ) $1.0 billion Direct medical charges (1993 dollars) -------------------------------------------------------------------------------------------------------- * Costs are actual economic costs whereas charges reflect the amount charged by a health-care provider. + This range is for the combined direct and indirect costs associated with foodborne illnesses caused by six pathogens: Campylobacter jejuni or Campylobacter coli; Clostridium perfringens; Escherichia coli O157:H7; Listeria monocytogenes; Salmonella (nontyphoid); and Staphylococcus aureus. & Preliminary estimates are based on the fact that human papillomavirus causes 82% of all cervical cancers ( 6-8 ); thus, charges were calculated by assuming that 82% of the following treatment charges are attributable to human papillomavirus: follow-up of precancerous lesions identified by Pap smear (1 million follow-up visits costing $1,100 each for a total of $1.1 billion) ( 6-10 ), treatment of carcinoma in situ (55,000 treatments costing $4,360 each, for a total of $0.2 billion) ( 6-9 ), and treatment of cervical cancer (15,800 treatments costing $11,300 each, for a total of $0.2 billion) ( 6-10 ). These estimates do not include indirect costs attributable to lost productivity or the cost of screening for cervical cancer. ======================================================================================================== Return to top. Figure_1 Return to top. Figure_1B Return to top. Disclaimer All MMWR HTML versions of articles are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the electronic PDF version and/or the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices. **Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov.Page converted: 10/05/98 |
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