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Summary and Assessment
Joshua Lederberg, Ph.D.
Nobel Laureate and Sackler Foundation' Scholar,
The Rockefeller University
Emerging infections are clinically distinct conditions whose incidence in
humans has been shown to be increasing (IOM, 1992~. These diseases continue
to disrupt the health care system, and successful detection and treatment of these
diseases is becoming increasingly complicated. The public health system also is
continually challenged by unexpected disease outbreaks, whether an influenza
epidemic or an act of bioterrorism. To be prepared and responsive to these in-
fections and outbreaks, the public health infrastructure requires attention and
resources.
Periodic infectious disease outbreaks serve to remind the public of the im-
portance of the public health system. That outbreaks and epidemics of infectious
diseases have been successfully prevented or controlled leads to the common
misconception that the public health system is more than sufficient. Such mis-
conceptions, however, belie the true risks to public health, and reinforce the
public's expectations in the face of increasingly complex emerging infections
and the changing health care environment.
Disease investigations are now more complex in nature than they were in
the past because of a variety of new pathogens and risk factors, outbreaks, and
bioterrorist activities that cross state and national boundaries often raising po-
litical and economic concerns. The ability to quickly recognize and respond to
widely dispersed disease outbreaks is a challenge to the public health system,
particularly in an era of increasing global population mobility and the wide dis-
tribution of centrally produced foods.
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2
PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
To further complicate matters, emerging infectious diseases are competing
with other types of diseases and with other health care priorities. The practice of
public health is moving away from the traditional focus on communicable dis-
ease control and into new arenas, such as chronic disease and injury prevention.
Simultaneously, public health programs have been dramatically underfunded,
with less than 1 percent of the $1 trillion investment allocated to health care
going to support public health functions (Margaret Hamburg, Assistant Secre-
tary for Planning and Evaluation, U.S. Department of Health and Human Serv-
ices, personal communication, November 19984. In the mid 1980s to early
1990s, the relative percentage was actually declining, despite a renewed atten-
tion to and appreciation of the critical role of public health, and the expanding
demands on public health systems. For example, in 1992 the United States spent
only approximately $74.5 million for all infectious disease surveillance through
the public health system (Michael Osterholm, state epidemiologist and chief,
Minnesota Department of Health, personal communication, November 1998~.
Another challenge facing the public health system is its fragmentation and
dependency on categorical funding systems at the national, state, and local lev-
els. Dependence on the one-time investments that states and localities choose to
make to support surveillance activities and dependence on the leadership that
may emerge by chance in the state or local public health department compro-
mise the sustained efforts needed to support the public health system. A renewed
commitment to a national approach to infectious disease surveillance is needed
both to support new requests for funding and to sustain the full range of activi-
ties related to infectious diseases that confront public health today.
To help inform the debate about the capability of the public health system to
respond to and control emerging infections, the Forum on Emerging Infections
convened a workshop—the subject of this workshop summary to identify,
clarify, and solidify some of the current and potential best practices in the public
health arena to combat the threat of emerging infectious diseases. The workshop
focused on four major areas of importance to public health systems that both
shape and are shaped by the nature of emerging infections: (1) epidemiological
investigations, (2) disease surveillance, (3) communication, coordination, and
education and outreach, and (4) strategic planning, resource allocation, and eco-
nomic support (see Appendix B. Workshop Agenda).
At the workshop, participants described the components of the current sys-
tem at the national, state, and local levels. In the ensuing discussions, partici-
pants debated many of the challenges that must be overcome and identified pos-
sible opportunities for addressing the obstacles. These discussions emphasized
three cross-sectoral thematic areas in which carefully placed investments could
make a positive contribution toward improving the capability of public health
systems to respond to emerging infections: (1) integration of public health sys-
tems, (2) investment in human capital, and (3) improved collaborations between
the private and public sectors.
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SUMMARYAND ASSESSMENT
3
This summary highlights the workshop presentations and analysis of the
discussions. The first section, Assessing the Capability, is a summary of the
presentations and discussions surrounding the four major topics of the work-
shop. The subsequent section, Strengthening the Capability, is an analysis of the
three thematic areas and the challenges and opportunities that the public health
system faces in each. The final section presents some concluding remarks. The
views and opinions discussed in this workshop summary, as well as the chal-
lenges and opportunities, do not necessarily represent the views of the Forum on
Emerging Infections or the Institute of Medicine.
ASSESSING THE CAPABILITY
Epidemiologic al Investigations
Because emerging infections continue to disrupt the health care system and
their detection and treatment are becoming increasingly complicated, it is essen-
tial that public health agencies frequently and methodically make every effort to
collect, assemble, analyze, and make available health information about the
community. This not only entails the provision of health status statistics and
community health needs but also requires epidemiological studies of health
problems. Diagnosis and investigation of health hazards within a community can
be performed by health departments at the federal, state, and local levels if they
have the appropriate levels of resources, adequately trained personnel, and es-
tablished systems of reporting and communication. Although each sector faces
some common and unique challenges, each component may also require coordi-
nation at several levels, from the local to the state to the federal level.
Federal resources, through the Centers for Disease Control and Prevention
(CDC), the Food and Drug Administration (FDA), and the Food Safety and In-
spection Service (FSIS), are available to assist in infectious disease investiga-
tions, but they can do so only if state and local public health agencies have the
infrastructures in place to detect and report unusual disease occurrences. Inves-
tigators at the federal level, largely through CDC, have better investigational
tools, such as computerized databases, computational technology, and electronic
mail, which has allowed individuals and federal agencies to recognize and report
incidents that might not otherwise have been detected. An additional important
service of the CDC is assistance with outbreak notification to other federal
agencies and jurisdictions. Finally, the CDC can assist with the implementation
of control measures.
Two other federal agencies also play a vital role in many foodborne illness-
related outbreak investigations because of their regulatory mandates. The U.S.
Food and Drug Administration, a sister agency to CDC in the Department of
Health and Human Services, has regulatory oversight over food products except
meat, poultry, and egg products, which is the purview of the Food Safety and
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
Inspection Service, the public health agency of the Department of Agriculture
(USDA).
In recent years, FDA has tried to improve its coordination of multi-state
outbreaks with CDC and other federal agencies. Because foodborne outbreaks
frequently involve low-level, sporadic contamination of widely distributed food,
often food from other countries, FDA must interact with multiple federal agen-
cies and jurisdictions. The FDA Division of Federal-State Relations aims to
conduct outreach and coordinate such efforts. In 1997, FSIS' Office of Public
Health and Science created the Epidemiology and Risk Assessment Division
that includes eight field epidemiologists who assist states, local jurisdictions,
and CDC with trace-back efforts during outbreaks where FSIS-regulated prod-
ucts have been implicated. Additionally, at the level of the Assistant Secretary
for Food Safety of USDA, the Foodborne Emergency Response and Rapid
Evaluation Team (FERRET) has been created to facilitate a prompt, effective,
and coordinated response to food emergencies by the many USDA agencies.
State health departments are often at the front line of outbreak investiga-
tions and receive news about an illness from many sources, such as the medical
care system, the public, the disease surveillance systems of other public health
institutions, or the news media. Once the cause of an outbreak is determined,
control and prevention measures must be implemented. These may include edu-
cating the population at risk, providing direct medical intervention (e.g., pro-
phylaxis with antibiotics), or ensuring withdrawal of a product from the market.
Documentation that details the process of the investigation, the findings, and the
recommendations is often required at the state level.
In general, epidemiological investigations and surveillance efforts at the
state level are challenged by a variety of factors, such as changes in the health
care system. In addition, many states are still using paper-based disease re-
porting systems. A number of states do not have a state epidemiologist, and the
responsibility of daily disease surveillance is often sporadic and inadequate.
Better computational resources could improve the system and accelerate dis-
ease reporting.
Local health departments face the strains of an insufficient infrastructure. At
a bare minimum, local health officials need basic investigational skills, such as
how to design appropriate questionnaires and improve interviewing techniques.
They also need to learn proper methods for the collection of environmental and
clinical specimens, as well as advanced computer and communications skills,
including skills that permit them to better interact with the media. Importantly,
they need to extend these skills beyond food-borne outbreak investigations,
which are the most common types of investigations at the local level, to investi-
gations of respiratory illnesses in school systems, occupational exposures, and
nosocomial infections. Local public health departments, however, are often
plagued with a high rate of staff turnover, poor pay, intermittent calls for indi-
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SUMMARYAND ASSESSMENT
5
viduals with unique skills, and inadequate financial support, thus making main-
tenance and continuity of skills difficult and training essential.
Historically, clinicians have played a central role in outbreak investigations
and disease surveillance. Long before the causative agents of infectious diseases
were known, the observations of medical practitioners served to alert the com-
munity to unusual medical occurrences. Even after the etiologies of infectious
diseases were unraveled and laboratory tests made available, clinicians still
played an essential role in providing patients for study and assisting in some
epidemiological investigations. Today, however, many physicians often are not
sure when or where to report suspicious cases of infection, are unaware of the
need to collect and forward clinical specimens for laboratory analysis, and may
not be educated regarding the criteria used to launch a public health investiga-
tion. Moreover, there is often a lack of communication among public health
agencies and community physicians.
Academic institutions must assume a primary role in keeping practicing
health professionals informed about the new knowledge, practices, and tech-
nologies that can be used to respond to emerging infections. Academic health
centers must capitalize on new technologies in continuing education, distance
learning, and executive training that make use of the Internet, wide-area com-
puter networks, and satellite-based communications capabilities. To be effective,
these activities must be conducted in close partnership with national, state, and
local public health organizations.
Cultural and conceptual gaps exist across the various disciplines and levels
that are involved in integrated and effective public health research and practice.
The key elements that comprise an integrated public health system include solid
capabilities in basic laboratory, epidemiological, clinical, behavioral, and health
care services, and policy research, as well as effective education and public out-
reach. The gaps among these elements include those that have historically ex-
isted between academic public health institutions and academic medical institu-
tions and between academic public health institutions and the larger health care
sector. The historical disconnect that exists between academic public health and
the larger health care sector, particularly as it pertains to private health care de-
livery systems and diagnostic laboratories, must be repaired to maintain ade-
quate responses to emerging diseases.
Surveillance
Surveillance is an early-warning system for diseases and must be the first
link in the chain of public health action, as it is an essential element for any dis-
ease control or eradication effort. It is a daily responsibility that at present is
somewhat sporadic and mostly inadequate in its current capability to anticipate
and detect early emerging disease trends in the United States. Surveillance is a
science and a tool, and is typically foreign to the traditional academic medical
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
curriculum in the United States. Although a tremendous amount of surveillance
is accomplished, much of it is disease-specific, resulting in disjointed programs
and unsustainable systems supported by categorical funding.
Traditional public health surveillance involves concurrent epidemiological
investigations, laboratory analysis, and health care delivery as well as the fol-
lowing activities: (1) identification of unusual clusters of disease and their geo-
graphic and demographic spread, (2) estimation of the magnitude of an outbreak
and a description of its natural history, (3) determination of the factors responsi-
ble for the emergence of a disease, (4) laboratory and epidemiological research,
and (5) successful specific intervention efforts. To accomplish this, public health
surveillance relies on the ongoing and systematic collection, analysis, and inter-
pretation of data that are reported to a central agency in a timely manner.
Public health surveillance systems can vary in their objectives, work scopes,
and methods, and in terms of whether they are either privately or publicly sup-
ported or operated. They can range from complex international networks to
small, community-based programs. Monitoring measures within these systems
are either passive or active. The characteristics that are vital to one system may
be less important to another. Moreover, efforts to improve the quality of one
system may impair the functioning of another system.
A public health surveillance network needs to have a balance of character-
istics from each system from the national, state, and local levels and from both
the public and the private sectors. One area of focus that can achieve that bal-
ance should be population-based strategies, which provide the foundation upon
which disease incidence and prevalence are enumerated and from which all sub-
sequent response activities originate. Population-based surveillance provides the
means to differentiate between anecdotal or temporal reports of cases and actual
outbreaks of infection. An emphasis on population-based disease surveillance
also necessitates the development of a set of standards for epidemiological in-
vestigations, laboratory analyses, case reporting across geographical and juris-
dictional boundaries, and personnel qualifications.
The public health capacity for population-based disease surveillance, how-
ever, is highly variable among states and varies even more widely among county
and local health departments. Disease surveillance systems at the national, state,
and local levels have developed independently in response to various health cri-
ses and needs, recent legislation, and available resources. Accordingly, there is a
need to integrate existing public health surveillance systems. For example, 50 to
60 different infectious disease surveillance systems exist nationwide. The re-
gionalization of surveillance systems and laboratory capacity is one means of
integration, but this issue requires further discussion.
The Emerging Infection Program (EIP) network, sponsored by CDC, is one
program that emphasizes the importance of population-based disease surveil-
lance and the dimensions and texture of surveillance information. The EIP net-
work has formed the basis of a surveillance system that needs continued and
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SUMMARYAND ASSESSMENT
7
increased support. This large, national effort has helped public health laborato-
ries to contend with the challenges of multiple jurisdictions and their reporting
requirements. This type of a network between the private and public sectors,
however, requires a certain level of data standardization, a goal that has not been
fully met.
A thorough review of the public health infrastructure is warranted to create
a new, comprehensive national plan to develop and apply established standards
for the public health infrastructure (laboratory, epidemiological, communica-
tions, and personnel standards) within and across the public and private sectors.
A national commitment is therefore necessary to maintain a network and its
readiness through standardization and proficiency testing. A national surveil-
lance plan should take into account the diverse surveillance uses of data, ap-
proaches, and emphases at different levels of government, as well as anticipated
capacity needs and scope of testing. Routine collection of surveillance data will
be an invaluable resource in retrospective analyses for surveillance purposes. In
addition, the results obtained from evaluations of these disease surveillance data
must be freely shared among federal, state, and local agencies, as well as be-
tween the public and the private sectors, for infectious disease surveillance to be
effective. Withholding of surveillance data on disease prevalence and incidence
for marketing and economic reasons can be detrimental to disease surveillance
activities.
Improving the infectious disease surveillance infrastructure requires coordi-
nation and collaboration, not the fragmentation and duplication of laboratory
services. A lack of standardization of the data elements to be reported can impair
the ability of the private sector to report back to the state epidemiology officer
and challenges the reporting systems of the state health laboratory. In addition,
disjointed programs as a result of categorical funding do not allow some states
to be able to monitor disease trends. For example, many states cannot afford to
monitor trends in the numbers of rodents with hantavirus infection, or assist
border communities in Mexico with monitoring efforts that may provide a win-
dow on the emergence of diseases such as dengue fever or cholera.
In the area of laboratory services, there is a particular need for adherence to
standard laboratory analysis practices, in part because of the unique role of the
public health laboratory. For example, the molecular characterization of patho-
gens is not a clinically relevant test and is typically not supported in the private
sector. Moreover, these tests can be costly because of the equipment, specialized
reagents, and skilled technical staff that are required. Yet these tests are a critical
weapon in the public health armamentarium as a means of combating emerging
infectious disease outbreaks because modern epidemiological investigations rely
on the modern laboratory tools of molecular biology for outbreak investigations.
Coordination and collaboration between public and private laboratory services
and the use of specialized diagnostic tests need to be encouraged and adequately
supported financially and politically. This collaboration extends to regulatory
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
agency laboratories which feed into PulseNet and similar team efforts, and work
to identify sources of foodborne outbreaks.
Coordination and communication will become increasingly important as
new partnerships are created and old partnerships are renewed. This will espe-
cially be the case if a national commitment to maintaining a disease surveillance
network and ensuring its readiness through standardization, proficiency testing,
and support of a staff of trained health care professionals is upheld. It is in the
areas of coordination and communications where a future role for public-private
partnerships that have not existed previously may be found. Partnership of pub-
lic and private entities will likely create new opportunities in infection control
and fiscal support for public health activities. A strong commitment to the de-
velopment of a national surveillance network and the strengthening of partner-
ships between the public and private sectors needs to be made.
Communication, Coordination, and
Education and Outreach
Clear communication is an essential function for effective coordination
across the public health sector to prevent and respond to disease outbreaks. It is
also a key element in the fight for sustained financial support of public health
activities. The components of public health and the core capabilities required to
maintain public health at multiple levels need to be understood by policy mak-
ers, regulators, and public health professionals. A uniform process for commu-
nication of the elements of public health can provide guidance as to the best
means to leverage opportunities among the public, academic, and private sec-
tors, especially by professional organizations. Although such communication
and uniform processes exist between federal and state public health systems,
timely coordination and implementation within states needs strengthening.
Barriers to effective and timely coordination and communication have their
roots not only in inadequate information technology but also in underqualified
and transient personnel. Continuing education and training programs developed
from an advocacy group perspective and targeted to the promotion of public
health surveillance within states may generate the intellectual and financial
commitments needed to strengthen the public health infrastructure. In this case,
opportunities exist for the private sector to participate in the direct support of the
infection control infrastructure.
For public health surveillance to be effective, there must be a free flow of
information among federal, state, and local agencies, as well as between the
public and the private sectors. Competition among and within the sectors is not
necessarily desirable and, in fact, can be detrimental to public health surveil-
lance activities. Agencies charged with conducting disease surveillance and re-
sponding to the surveillance findings need to have well-established communica-
tions systems that can facilitate the timely collection of surveillance data and
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SUMMARY AND ASSESSMENT
9
transmission of alerts about emerging infections across the country. The systems
must also be able to share rapidly the information with those who need to know.
These communications systems are hampered by the need to transmit informa-
tion across state lines, to federal agencies, and to a variety of local and intrastate
groups, including health departments, other state agencies, laboratories, emer-
gency departments, hospitals, physicians, the public, and the media. Too often,
however, communications systems at the state and local levels are outdated,
situational, and low budget. Few assessments of their sufficiencies have been
conducted, and no standards or guidance for the development of such systems
exist. In addition, many state governments are further hampered because they
have little information on technology capability and are discouraged from de-
veloping it because of downsizing.
Opportunities are available, however, to improve communications channels
between the scientific and policy-making communities, among all levels of gov-
ernment, among professional health care organizations, and between public
health officials and the public. This requires intellectual, political, and financial
commitments. It requires resources dedicated to the training of individuals who
deliver public health services. Effective sharing of information obtained from
population-based surveillance and control efforts also needs the same commit-
ment. The education of clinicians who must report the data and care for patients
must not be neglected. Likewise, the development of more streamlined, accu-
rate, and standardized medical record keeping is needed within and between the
public and private sectors.
Strategic Planning, Resource Allocation, and
Economic Support
Many improvements in the health of Americans have been achieved
through public health efforts. Vaccination programs, safe food and drinking
water, and responses to disease outbreaks are among the advances in public
health that prevent untold morbidity and mortality and improve the quality of
life. The American people value public health, and many see the core functions
of public health as essential services that are provided by federal, state, and local
governments. However, when the public health system is functioning well, it is
invisible to the public and is taken for granted.
The U.S. Congress is generally supportive of public health activities that in-
volve emerging infectious diseases. The general message received by Congress
is that research is good for everybody and that research will make people
healthier and will save Medicare dollars. There is, however, competition for
research funds. Policy makers and the public identify with diseases. The most
successful groups receiving research funding are those that are disease-specific,
such as groups advocating funding for cancer or diabetes research.
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
The various components of the public health system are difficult to explain
and promote to the public and to those who appropriate funds. Furthermore,
infectious diseases are not seen as a health threat to Americans but, instead, are
seen as a problem primarily faced by people in other counties. It is thus difficult
to communicate the urgency and importance of maintaining current infectious
disease prevention and health promotion programs to meet future infectious dis-
ease threats, especially when the public does not perceive infectious diseases to
be important.
Consequently, public health is poorly understood by the public and by pol-
icy makers and decision makers. Despite a renewed attention and appreciation of
the critical role of public health and the expanding demands of public health,
public health programs have been dramatically underfunded, with less than 1
percent of the $1 trillion investment from health care going to support public
health functions. For fiscal year 1999, the Senate Appropriations Committee is
able to devote a $3.2 billion increase for the agencies of the Public Health Serv-
ice, translating into a 14.5 percent increase from previous fiscal year (Jack
Chow, Labor, Health, and Human Services Subcommittee, Senate Appropria-
tions Committee, personal communication, November 1998~. Public health's
fiscal survival depends on categorical funding streams that may vary at the state
and local levels and on unique investments that states and localities choose to
make in supporting surveillance activities. Its fiscal survival is also affected by
the chance that leadership may change in the state or local health department.
Because the public health system is highly fragmented, a renewed commit-
ment to a national approach to public health and infectious disease surveillance
with well-defined roles for state and local governments is in order. This is
needed to support both new requests for funding and the full range of infectious
disease issues that confront public health today. If the public health system is to
care for the public's health, the focus cannot be solely on health care delivery
systems. It is important that the public and policy makers are aware of the range
of often unique services that public health can provide to promote health and
prevent diseases.
Advocating for public health is often difficult, especially if those people and
organizations that are best suited to be advocates are understaffed, have inade-
quate resources, may have real or perceived limitations on their ability to lobby,
and are not experienced in the art of advocacy and communication. Yet, mem-
bers of the U.S. Congress, state legislators, and managed care organizations
must be educated about the needs of the public health system, particularly the
public health infrastructure and its role in combating emerging infections.
Emerging infectious diseases are but one concern of the public health sys-
tem. In addition, the issues that surround emerging infections are different from
those of other public health concerns. Until public health laboratories and clini-
cal departments have the resources and infrastructures necessary to meet the
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SUMMARYAND ASSESSMENT
11
challenges of emerging infectious diseases, planning will remain reactive rather
than strategic.
A common language targeted toward policy makers and patients would be a
first step to communicating effectively the challenges that the public health
community faces in its struggle to build and sustain the necessary infrastructure
to combat emerging infections. Short, succinct, nontechnical dialogue with the
public and decision makers is needed when advocating for greater core support
at the local, state, and national levels.
STRENGTHENING THE CAPABILITY
The workshop presentations and subsequent discussions converged on the
overriding need to strengthen and support the core capability of the public health
systems for infectious disease surveillance, response, prevention, and control.
Variations in the capabilities of public health departments to detect and respond
to disease outbreaks point to the need for public health departments at all levels
to define their core capacities for epidemiological investigations, particularly as
those capabilities relate to the activities of the public health laboratory. For ex-
ample, surge capacity in response to an outbreak is one area in which the public
health laboratory can begin to define its core capability and standards. Improved
communication and collaboration between the private and public sectors may
enhance the core capability and bridge the gap between clinicians and public
health practitioners. The need for collaboration among disciplines and the need
to bring in new partners from commercial laboratories in particular and nongov-
ernmental organizations in general, emphasize the fact that additional resources
will be needed to implement new mechanisms to provide for the public's health.
Opportunities are available, however, to improve communications channels
between the scientific and policy-making communities, between the local and
state levels and the national level, among professional organizations, and among
public health officials and the public. This requires intellectual, political, and
financial commitments. It requires resources dedicated to the scientific training
of individuals involved in the delivery of public health services, to effective
sharing of information from population-based surveillance and control efforts, to
the education of clinicians who must report the data and care for patients, and to
the development of more streamlined, accurate, and standardized medical record
keeping.
The discussions at the workshop emphasized three cross-sectoral thematic
areas in which carefully placed investments could make a positive contribution
toward improving the core capability of public health systems to respond to
emerging infections. These areas are assessed below.
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13
Although there are common uses of surveillance data at the local, state, and
national levels, the emphasis on these data varies. For example, investigation of
individual cases is critical at the local and state levels but less so at the federal
level (unless a disease outbreak occurs across state boundaries). On the other
hand, evaluation of larger-scale prevention and control measures (for example,
the impacts of new vaccines) is a high priority at the federal level. A national
surveillance system should take into account this diversity in the uses of data,
approaches, and emphases at the different levels of government. Along with
these benefits of Internet-based information systems, however, patient confiden-
tiality must be carefully considered.
Modern infectious disease surveillance needs to move beyond traditional
paradigms of disease surveillance and reporting. A nationwide infectious disease
surveillance network will involve a unified strategy for epidemiological investi-
gations in which the infection control community, the media, and informed pub-
lic work more effectively at the state and local levels. It will need to better in-
corporate research results and new technologies as they become available from a
wide array of sources. It will require an integrated public health system that
collectively helps evaluate the public health implications of a disease uncovered
during an outbreak investigation while data are still being gathered. These new
data can provide impartial advice for timely and appropriate prevention and
regulatory actions.
Specific considerations promoting the integration of public health systems
toward the development of a nationwide infectious diseases surveillance system
are discussed, as follows:
. Increase the use of novel surveillance systems and modeling tech-
niques to help predict, detect, or monitor disease trends, environmental and
climatic conditions, or genetic shifts that suggest disease outbreaks and fa-
cilitate epidemiological investigations. Improved methods are needed to iden-
tify the risk factors associated with disease outbreaks. Better understanding of
the root causes and determinants of outbreaks can then be used to initiate pre-
vention programs and mitigate the impact and spread of an infectious agent.
However, to protect the public from emerging infections, it is not sufficient to
culture only contaminated specimens, determine the nucleotide sequence of a
pathogen or its isolate, and identify a new pathogen from an infected individual;
rather, surveillance activities should examine the continuum of disease.
Surveillance is becoming increasingly complex owing to a number of factors,
including the change and loss of habitats worldwide, the interaction of humans
with animals and disease vectors, and increased global travel. Although some
intermediaries of disease are monitored (e.g., chickens and encephalitis), most
are not. Although the monitoring of vectors (e.g., the tiger mosquito) is
inadequate, it can serve as an early-warning system for human disease. Ideally,
surveillance should have the capacity and scientific capability to monitor human
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PUBLICHEALTHSYSTEMSAND EMERGING INFECTIONS
health in light of pathogen mutagenicity and changing environmental factors.
Likewise, the utilities of biological, ecological, environmental, climatic, and
behavioral factors need to be validated for the development of new algorithms
and other analytical methods that can be used to forecast disease outbreaks.
. Protect the confidentiality of medical records and preserve the mis-
sion of public health. The need to enhance the disease surveillance capacity of
public health systems and the need to communicate this information is con-
founded by the need to protect patient privacy. Public unhappiness with man-
aged care and concerns about the confidentiality of medical records have re-
cently focused attention on the need to develop better means to protect patient
medical records and medical information. However, quality disease surveil-
lance often requires the use of a name-based data system to track individual
cases of disease. A means of ensuring the ability to conduct quality surveillance
and, at the same time, the appropriate protection of patient and consumer in-
formation is needed. The impact of systems and legislation designed to protect
patient confidentiality in association with infectious disease surveillance re-
mains to be determined.
. Define the minimum communications capacities and technologies
needed to respond to infectious disease epidemics and pandemics, whether
they occur naturally or are purposefully induced. The establishment of a
system that assesses and responds to the health needs of a population cannot
simply focus on health care delivery systems. Responses to new disease threats,
ranging from naturally occurring outbreaks to bioterrorist activities, will require
unique services that the public health system can provide to promote health and
prevent disease. Defining these mechanisms to build a fundamental, integrated
capacity for infectious disease surveillance and communication will lay the
foundation for a first line of detection and response to potential bioterrorism
incidents or the threat of influenza pandemics.
. Develop intrastate and interstate integrated communications systems
as part of a nationwide infectious disease surveillance system. Frequently,
communications systems at the state and local levels are outdated because of
funding, technological, or situational constraints. For example, funding limita-
tions in some health departments currently rely on surface postal delivery and
direct oral communications as the standard means of communication at the in-
trastate level for all messages except those that are most urgent. Conversely,
interstate and national communications rely on video- and teleconferencing to
relay high-quality information. Moreover, few standards or little guidance have
been established for the creation of uniform criteria for effective disease report-
sing, and communication systems.
On the technical side of communications, public health systems need to be
fully integrated with modern computer information systems. Internet-based
communications systems have the promise of linking local and state health de-
partments, hospitals, managed care organizations, and federal agencies respon-
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15
sible for infectious disease surveillance and response. The rapid exchange of
information through the Internet could be the mechanism needed to strengthen
the infrastructure in infectious disease surveillance and data collection in real
time. Along with the benefits of Internet-based information systems, however,
the issues surrounding patient confidentiality must also be carefully considered.
The opportunities of computerization in the context of a failing public
health system should not allow one to be seduced into a sense of accomplish-
ment, however. The Internet is still limited as a communications tool within
states and many health care professionals and institutions do not have access to
it. Except for academic health centers, most health care providers, emergency
departments, and hospitals do not have Internet access, much less a centralized
e-mail system.
Further consideration must be given to the validity of the information
shared. Rapid linkage of public health departments and laboratories with other
health care providers, managed care organizations, and national centers is only
as valuable as the quality of the data collected and the capacities of the epidemi-
ological and laboratory surveillance systems. The establishment of standardized
and integrated disease surveillance databases is one of the first steps that will
require intellectual, political, and financial commitments to develop the art of a
nationwide surveillance system. Already there are a variety of disease surveil-
lance databases found nationally, within health departments, among hospitals,
and across the managed care systems. Rapid communication combined with
common algorithms for pathogen and disease identification, adherence to safety
protocols, and recognition of an outbreak highlight the growing complexity of
and difficulties with the integration of public health databases for disease sur-
veillance purposes. Given the current trends of downsizing within state and local
health departments, it is unlikely that intrastate communications will improve
unless there is increased political will and financial commitment.
. Determine CDC's capacity to review additional data, assess new
situations, and determine appropriate responses if CDC investigators have
already been diverted to other disease outbreaks at domestic or interna-
tional sites. Previously unrecognized diseases are appearing with alarming fre-
quency, both domestically and internationally. Placed against a background
prevalence of known diseases, outbreaks of unknown origin place a severe strain
on any public health agency. This is particularly the case given that there is a
nationwide dearth of well-trained and experienced health care professionals ca-
pable of investigating exotic pathogens. Because of the impacts of disease out-
breaks on health, economies, trade, transportation, and national security, the
capacity of CDC to respond to multiple disease outbreaks needs to be evaluated.
Similarly, an assessment is needed on how to achieve better coordination among
CDC, state health departments, and regulatory agency (FDA and FSIS) field
investigative teams.
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PUBLIC HEALTH SYSTEMS ANrD EMERGING INFECTIONS
. Develop communication systems to facilitate the ability of large
commercial laboratories to rapidly share data with multiple jurisdictions.
Each public health laboratory resides in a fairly unique health care and public
health system, and each operates a fairly unique information system. Problems
of further fragmentation of a system of laboratory networks are evident as labo-
ratories whether they are local, commercial, or public conduct increasingly
smaller numbers of routine tests for the diagnosis of infectious diseases. The
need to communicate or share data with collaborating or other laboratories
therefore becomes less frequent. Thus, the traditional system of communica-
tions and maintenance of the collegial relationships that fostered the exchange
of information and disease reporting are similarly breaking down. Electronic
linkages with large commercial laboratories and health care providers in the
community, with the national centers and reference laboratories, and within a
health department and across jurisdictions will be key to effective infectious
disease surveillance.
Investment in Human Capital
Without a clear commitment to invest in human capital, the entire fabric of
the public health system is ineffective. One cannot object to the need for sus-
tainable systems, interconnectivity, communication, capacity, advocacy, and
planning; however, a dearth of public health professionals trained in epide-
miology and surveillance is presently a concern. Some of the factors that con-
tribute to this shortage include inadequate salaries, staff development, re-
sources, and academic partners and a lack of an appropriate curriculum, as well
as a lack of a multiyear grant or budget cycle that has the potential to create an
incentive for state and local health departments to invest in personnel. It is
therefore vital that programs that teach population-based science to trained
health professionals in epidemiology and surveillance be developed along with
programs that retain these professionals in state and local health departments.
The following items were identified as providing a possible framework for ac-
complish these objectives.
. Develop targeted public health training programs. Building the public
health workforce requires two interrelated actions: (1) development of the future
workforce, and (2) retention of the workforce once it is trained for a career in
public health. Historical distinctions between public health and medicine have
resulted in the marginalization of public health by medical students and new
physicians. Adequate exposure of medical students to public health activities so
that they may consider the possibility of a career in public health, greater famili-
arity with the tools of public health, and promotion of an awareness of the role
of the practitioner in the public health system all need further development.
Academic institutions and professional organizations are uniquely positioned
to engage more directly with public- and private-sector organizations in designing
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1
7
tailored training programs for their workforces. Training programs targeted to the
public health and commercial laboratory workforce need to be strengthened. Aca-
demic health centers are also the intellectual hub for training public health profes-
sionals. Here there is an opportunity for increased investment in education and
outreach for all health professionals in the area of emerging infections and, in par-
ticular, the area of antimicrobial resistance—conditions that are population-based.
Multidisciplinary approaches are needed to educate medical and public health
professionals on the pathobiology of infectious diseases.
Additionally, there is a lack of public health professionals trained in epide-
miology, which undermines the capabilities of public health. Surveillance sys-
tems must be in place to ensure that state-level responses to outbreaks are ade-
quate, appropriate, timely, and efficient. To respond to and investigate these
outbreaks, adequate resources are necessary at the local, state, national, and in-
ternational levels. Resources include not only computers, laboratory equipment,
and environmental monitors but also adequate numbers of trained epidemiolo-
gists. Investments must be made in the training of new public health profession-
als and in the retention of experienced professionals.
The need to better communicate public health matters to the public and
policy makers is clear. However, one of the problems facing the public health
system is a sense of continuity and leadership reflected by a continuation of in-
dividuals in public health roles. Reports from the Association of State and Ter-
ritorial Health Officials reveal that the average time of service for a commis-
sioner of health is less than 2 years. Many of these positions are filled by
political appointees who have some experience in health—often in health care
delivery or disease care delivery, but not in public health. The leadership pro-
vided by a public health commissioner affects the role of public health depart-
ments in the changing picture of the health care system.
. Promote linkages among academia, the medical community and the
public health sector. Efforts that support linkages between academic public
health institutions and professional organizations could help encourage the
practice of public health as a chosen academic profession. Currently, population-
based sciences such as epidemiology and concepts of surveillance are not main-
stays in health professional training. However, academia is equipped to provide
continuing education in these areas. Collaborative research between academia
and public health departments needs to be more strongly encouraged and
funded. Because practicing physicians require greater awareness of issues re-
lated to emerging infections, disease reporting, and population-based health, it is
essential that creative and innovative continuing education programs be devel-
oped by public health, organized medicine, and academic communities. Aca-
demic institutions must engage more directly with public- and private-sector
organizations in designing training programs tailored for their workforces.
Changes in the health care system are causing concerns about the traditional
way in which disease surveillance is conducted. Traditional patterns of reporting
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
are lost as the source of health care delivery shifts from the inpatient to the out-
patient setting. Lost is the dedicated epidemiological reporting system found
within the inpatient setting. Cost-containment factors, increased patient loads,
and new demands in the outpatient setting are placing increased pressures on
providers' time and expertise. The resulting trend of the greater use of empiric
treatment, which helps to alleviate some of those pressures, may actually be
decreasing the level of reporting of information on infectious diseases. A critical
issue then becomes the role of the physician in public health and infectious dis-
ease surveillance. Efforts to increase the linkages between the medical and pub-
lic health communities are needed early in the physician's training and through-
out his or her career.
Cultural and conceptual gaps exist across the various disciplines that need
to be more allied in effective public health practice and research. Key elements
for an integrated public health system include basic laboratory research, epide-
miological research, clinical research, behavioral research, health care services
and health care policy research, and education and public outreach. The histori-
cal disconnect between academic public health and the larger health care sector
must be repaired so that the responses to emerging diseases are more effective,
particularly as this disconnect pertains to private health care delivery systems
and diagnostic laboratories.
. Funding sustainable careers. Efforts need to be made to reconsider
yearly line items in budgets for investments in personnel. One-year grant cycles
do not encourage investments in recurring costs, such as personnel. A more
creative approach to grants and grant cycles needs to be considered to give states
and local health departments an incentive to invest in human capital. In addition,
steps must be taken to encourage revamping the 1-year grant cycles to invest in
personnel. One-year grant cycles do not reinforce investments in recurring costs,
such as personnel.
Sustainable careers are also dependent upon the development of regional
capabilities for training, interpretation, problem solving, and improvement of
information technologies, as well as regional approaches to planning, as a prac-
tical solution to limited resources and disparate state and local laboratory capa-
bilities. It is difficult to develop the kinds of career ladders within public health
that are important to the retention of good people. Support of regional capabili-
ties for ongoing training in continuing medical education is needed to promote
careers in public health and create meaningful career ladders and opportunities
for professional development. Additionally, regional approaches to planning
should be encouraged as a practical solution to limited resources and disparate
state and local laboratory capabilities.
There is also a need to expand CDC's Epidemiologic Intelligence Service
(EIS) program at the state and local levels to train public health professionals in
epidemiology and surveillance. In the area of foodborne-illness investigations
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SUMMARYAND ASSESSMENT
19
outbreak-related field activities included should be for the EIS officer with FDA
and FSIS as part of the EIS training experience.
Finally, even though the PulseNet program has experienced many suc-
cesses, it is stretched in its ability to subtype every isolate and to follow up with
appropriate epidemiological investigations because of a lack of trained person-
nel resulting from inadequate funding. As such, more support is needed for this
program in order for it to successfully reach it's ability to conduct timely sharing
of information that can facilitate the recognition of an outbreak.
Improved Collaborations Between the Public and
Private Sectors
A disconnect exists between the needs and abilities of the public and private
sectors when it comes to disease surveillance. Although commercial interests
have unique capabilities to conduct the type of testing required by the public
sector, they do not have the incentives or resources. On the other hand, detailed
epidemiological follow-up studies are most suitable for the public health sector.
Both sectors have necessary roles.
Public-sector laboratories play an important role because of the unwilling-
ness of private laboratories to voluntarily perform activities that will not make
profits and because of the more direct accountability of public-sector laborato-
ries to elected officials and the public. Despite these factors, public sector na-
tional laboratories need ample opportunities to collaborate with academic and
private-sector facilities to help standardize databases and evaluate reagents and
techniques. Such collaborations will be particularly important in response to
changes in the ways in which health care is administered and as the need for cost
containment continues to grow. For example, one area of collaboration is re-
ferred to as "split sampling" whereby partnerships are formed between public
and private laboratories. Split sampling can be defined as follows. As the com-
plexity of disease investigation increases, the complexity of laboratory testing
increases and some necessary tests will remain relatively rare, expensive, and
very scientifically precise. Therefore, to verify results, many specimens ana-
lyzed in a public laboratory may need to be split, with half of the sample sent to
commercial laboratories for rapid analysis or for analysis with arcane, costly,
and unusual rare reagents. Although split sampling is expensive and is an ac-
cepted standard for samples whose results will require legal or regulatory action,
it is not reimbursed by traditional health plans. Nevertheless, isolates and speci-
mens examined by split sampling, an essential procedure to confirm the pres-
ence of a specific pathogen, come from various health care settings. Specific
opportunities to promote public-private sector collaborations include:
. Leverage the potential advantages of working with managed care. The
transformation of the health care system has created an adversarial relationship
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
among public health officials, managed care organizations, and state legislators.
For example, an overemphasis on economic efficiency and cost containment cre-
ates disincentives for disease reporting and isolate submission. In addition, con-
tracts with large national commercial laboratories may create barriers to com-
plying with state and local disease reporting requirements. Yet, a common issue
underlying these negative effects of managed care is the lack of adequate funding
for support of the public health infrastructure. Managed care plans have inte-
grated databases that could be used by public health systems to track infectious
diseases among the plans' populations. Likewise, there is a potential for seamless
communication between public and commercial laboratories, managed care or-
ganizations, and public health officials. The development of partnerships with
managed care organizations may be one way in which public health laboratories
could share databases and contain infrastructure costs. Additionally, standardized
contract language could be developed to bind public health laboratories and man-
aged care to foster partnerships.
. Define the unique and complementary roles of the public- and pri-
vate-sector laboratories and identify their core capabilities. States and large
local jurisdictions must have the expertise and experience needed to rapidly
mount laboratory investigations in response to disease outbreaks. Additionally,
federal agencies with outbreak-related laboratory missions, including CDC,
FDA, FSIS, and DoD, need to have an adequate level of expertise to rapidly
identify new threats which emerge. Public health laboratory expertise is one
function that should not be fully privatized because the role of government in
protecting the nation's health will inevitably determine laboratory investments.
However, the competitive environment of managed care, the growth of inde-
pendent laboratories, and the consolidation of hospital laboratories influence
some of the important shifts in the capacities of public health laboratories. A
means of fostering closer partnerships between public and private laboratories is
needed to help develop compatible surveillance and reporting systems. For ex-
ample, public health departments could receive data on disease incidence from
the private sector. These data would then be integrated into a larger national
public health surveillance system. Special emphasis could also be placed on
hospital emergency departments, which are frequently vital sources in the re-
porting of disease outbreaks. Coordination of these capabilities will become a
key element to determine where the locus of activity should lie for a given dis-
ease or outbreak situation.
. Regionalization of state public health laboratories. The functions of the
public health system are highly fragmented across national, state, and local lev-
els, as well as between the public and private sectors. Use of strategies such as
cost subsidization for certain routine tests and for more specialized kinds of
services is one way in which public health laboratories are trying to remain eco-
nomically viable and yet sustain their responsibility for infectious disease sur-
veillance. Some public health laboratories are also focusing some of their efforts
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SUMMARYAND ASSESSMENT
21
on various activities that have importance for government functions. This has
created dilemmas for state and local public health laboratories in terms of where
they should set their priorities. It may be time to consider the regionalization of
state public health laboratories. Areas of focus for such regionalized public health
laboratories would be the use of certain kinds of expertise and specialized ca-
pacities that have limited commercial value but that have enormous consequences
for public health and safety. A renewed commitment by the public and private
sectors to a coordinated national approach to public health and infectious disease
surveillance is needed to support new requests for funding and to sustain the full
range of infectious disease-related activities that confront public health today.
. Systems to evaluate diagnostic reagents and techniques. Comprehen-
sive infectious disease surveillance is beyond the capacity of any one laboratory,
whether it is public or commercial. For example, adequate evaluation of diag-
nostic reagents and methodologies and ensuring that the techniques used are the
most appropriate for the assumptions of the test are labor- and resource-
intensive. Yet, laboratory results, results of data analyses, and interpretations
vary if standardized techniques are not followed. Specialized techniques in
modern biology and the skilled personnel needed to perform those tests are usu-
ally too costly for most laboratories but could be obtained through the use of a
regional system and private-public partnership. A unified system of sharing
materials and methods would be an invaluable tool for rapid communication,
pathogen and disease identification, establishment of protocols for safety, and
enhancement of the ability to detect multijurisdictional outbreaks.
. Educate members of the U.S. Congress, state legislators, and gover-
nors about public health activities and indicate to these individuals that
mere additions to, or extensions of, existing categorical funding are insuffi-
cient to meet the public health system's needs. The U.S. Congress has come
to appreciate the value of basic research and could similarly come to appreciate
the need for an adequate public health infrastructure and nationwide system for
infectious disease surveillance. Issues related to emerging infectious diseases,
including bioterrorism, food safety, antimicrobial resistance, and vaccination
programs, could be used to promote the need to build the fundamental capacity
for integrated infectious disease surveillance as an important first line of action
in detecting and responding to infectious diseases. This is an opportunity for the
public health community to create partnerships with patient advocacy groups.
. Expand private sector investments in public health research so that
public health services, applications, and prevention research are funded at
sufficient levels to accommodate discoveries derived from basic research.
The driving force behind advances in disease surveillance, prevention, and re-
sponse is a vigorous and multidisciplinary basic and targeted research enterprise.
Public, policy makers, and public health practitioners need to stay informed
about recent research results and applications of discoveries related to under-
standing of diseases. The timely analysis and dissemination of surveillance data
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PUBLIC HEALTH SYSTEMS AND EMERGING INFECTIONS
gathered through public-private sector collaborations could promote better pa-
tient care. Physicians could be better informed with the latest medical informa-
tion and better able to provide their patients with the most appropriate care and,
at the same time, reduce the risk that an infectious disease is spread to the larger
community.
CONCLUDING REMARKS
The changing face of health care poses new challenges for the detection,
treatment, and prevention of infectious diseases. Historically, public health de-
partments, hospitals, and clinics have been the main sources for the detection
and treatment of infectious disease outbreak. State and federal laboratories have
been the driving force behind surveillance. The function of the public health
system is diffuse, with managed care organizations and industry playing new
roles. All of this comes at a time when the communications potential is en-
hanced by the existence of the Internet and large, accessible databases. These
combined forces simultaneously place new pressures on and offer new opportu-
nities to the public health system. Yet, the basic infrastructure of the public
health system, particularly at the state and local levels, is eroding. With that de-
terioration comes a diminished capacity to predict, detect, and respond to an
emerging infectious disease.
An adequate public health system is made up of various components. A1-
though the list presented below is not comprehensive, it nevertheless provides a
good representation of the components that should be considered. The changing
demographics and environmental conditions that the United States and countries
around the world are experiencing have important influences on public health and
include global travel; immigration and migration; movement of products, includ-
ing food and other potential vectors of disease; population growth; urbanization
and crowding; changing socioeconomic conditions, particularly the worsening
poverty observed in so many areas of this country and other parts of the world;
and significant ecological changes such as deforestation, reforestation, irrigation,
and changing patterns of agricultural and pesticide use. These changes are dy-
namic and contribute to the complexities of emerging infectious disease outbreaks.
Because of such events, the need for the development and implementation
of a fundamental capability for infectious disease surveillance at the community,
state, and national levels cannot be overemphasized. Uniformity needs to be
established in the currently fragmented public health systems, particularly in the
public health laboratories that exist throughout the country. If the United States
is to have a robust public health system, ongoing training and the creation of
meaningful career ladders and opportunities for professional development within
the practice of public health need to be established and considered priorities.
Additionally, public health systems must be completely integrated into the
computer age. The current standard for laboratory reporting in most state health
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SUMMARY AND ASSESSMENT
23
departments is still surface mail, with a measured 10- to 14-day lag time in some
states. To speed up the reporting process, public health systems need to seriously
consider application of computer and electronic communications technologies to
their laboratory reporting systems. It is also critical for health departments to
have electronic linkages with other health care providers in their communities
and with national centers such as CDC, as well as to explore the issue of data
integration and data comparability both across systems within a health depart-
ment and across the various levels of the public health systems.
Public health systems also need to enhance their capability to communicate
critical information, particularly information about the risk of an infectious dis-
ease outbreak. Intrastate communications systems are often underdeveloped,
lack standardization, and are rate-limiting steps in some forms of communica-
tions. The development of laboratory listservers would increase real-time con-
nections and therefore enhance the communications capabilities to detect, as-
sess, and respond to emerging infections and outbreaks. Public health systems
also need to further explore and have the capacity to have Internet-based bulletin
boards for the reporting of information on emerging infections. The electronic
and computer media are also especially important for clinical laboratories since
this would enable clinical data to be manipulated into a form in which it could
be sufficiently standardized and shared among institutions and organizations.
This process could begin to facilitate everything from public health surveillance
activities to clinical trials that require cross-institutional coordination and coop-
eration. These actions would promote the development of a much-needed na-
tional disease surveillance system.
Public health systems must also embrace the human component. They need
to attract and maintain a cadre of public health professionals who are well edu-
cated and knowledgeable about technologies. Training opportunities must be
made available to these professionals to keep them up-to-date on pertinent issues
that would increase their knowledge and capabilities on public health issues,
including surveillance and epidemiological investigation issues. Additionally, to
attract and retain these professionals, public health systems must be willing to
compensate them adequately. Salaries need to be competitive not only for public
health professionals (including epidemiologists and laboratorians) but also for
the information technology personnel who work in the public health arena. For
example, many hospitals cannot compete in the current technology marketplace
for the best networking and computer experts because high-technology compa-
nies can provide them with much more competitive salaries.
Lastly, the public health infrastructure should contain a number of qualita-
tive features. Not only does it need to be sustainable but it should be adaptable
and capable of anticipating future problems. An adequate public health system
should also have an infrastructure that can quickly adjust to a given portfolio of
problems and that should be resilient, transfo~ative, and able to be revised
when necessary.
Representative terms from entire chapter:
infectious disease
