Good morning. I want to thank you, Senator Frist, and the Subcommittee for your invitation to
testify at this critical hearing on global health and the U.S. response to infectious diseases. My
name is Stephen Blount. I am the Associate Director for Global Health at the Centers for
Disease Control and Prevention (CDC), a physician and epidemiologist.
We appreciate this opportunity to present CDC's perspective on the pressing need for
infrastructure to maintain surveillance and respond to outbreaks of infectious diseases and on the
need for collaborative efforts in prevention, monitoring, and controlling infectious diseases
worldwide. My testimony will review CDC's accomplishments in global disease control
activities and our future plans to protect the U.S. and work with WHO and others to enhance
global response capabilities against infectious disease threats.
CDC has a proud history of working with other U.S. agencies, international organizations, and
individual nations, to promote health and prevent disease. CDC provided leadership, in
partnership with United States Agency for International Development (USAID) and the World
Health Organization (WHO), in the historic efforts leading to the global eradication of smallpox
in 1977. Over the past 20 years we have worked closely with these organizations and others to
apply the lessons of smallpox eradication toward the goals of global elimination of polio and
guinea worm and hemispheric elimination of measles, both by the year 2000. Throughout those
20 years we have also worked with a variety of partners to strengthen the global capacity
necessary to address infectious disease threats in developing countries.
Growing concern about the global threat of emerging infectious diseases was described in a 1992
policy report issued by a committee of the Institute of Medicine (IOM) of the National Academy
of Sciences co-chaired by Robert Shope, a distinguished virologist, and Nobel Laureate Joshua
Lederberg. The report emphasized that addressing this threat would require a global strategy, and
it challenged the U.S. government to take action. CDC answered that challenge in 1994 by
launching a national effort to revitalize the U.S. capacity to protect the public from infectious
diseases. This effort was described in Addressing Emerging Infectious Disease Threats: A
Prevention Strategy for the United States, copies of which are here.
Before I review with you some of CDC's accomplishments and activities in the area of global
health, I first want to emphasize that infectious diseases honor no national boundaries. The
deadliest infectious diseases can emerge from the markets of Hong Kong or the rainforests of
Africa and are only a plane ride away from any major city in the world. Infectious microbes
have proven that they can easily travel across borders with their human or animal hosts.
Controlling disease outbreaks in other countries is a necessity, not only for humanitarian reasons,
but also to prevent those diseases from spreading globally, including to the U.S. Moreover, U.S.
support for disease investigations in other countries provides U.S. scientists with opportunities to
learn about new pathogens -- like the new strain of influenza virus in Hong Kong or the deadly
Ebola virus -- and to discover how best to control, prevent, and treat them--before they reach our
shores. All of these efforts are beneficial both to U.S. citizens and to the global community.
Thus, it is no longer possible to protect the health of U.S. citizens without addressing infectious
disease problems that are occurring elsewhere in the world. As stated in the 1996 Presidential
Decision Directive on Emerging Infectious Diseases, the U.S. is committed to working with
international partners to promote an inclusive, global network for surveillance and response to
infectious diseases. CDC has a major role to play in this important endeavor.
I want to take this opportunity to describe some of CDC's accomplishments in five broad areas
related to the global problem of emerging diseases: surveillance, outbreak response, building
global capacity, disease eradication, and applied research. I will also indicate our future plans.
Disease Surveillance
In order to protect ourselves, we must be able to identify infectious disease threats, and disease
surveillance is our major tool. Like the United States, many countries are trying to improve their
national capacities for disease surveillance and response. It is especially important that disease
surveillance be enhanced in developing nations, where emerging diseases may go undetected for
long periods of time. CDC is working with partners throughout the world to further this aim,
helping to enhance both human and technical resources.
A fundamental component to building global capacity is to strengthen existing institutions in this
country. For example, CDC has helped enhance surveillance and response capabilities at 30
U.S.-based WHO Collaborating Centres, which help diagnose diseases and control outbreaks
around the world. A new WHO Collaborating Centre on Control of Epidemic Meningitis,
established at CDC in 1996, provided the technical lead in an international effort to respond to a
meningitis outbreak in Sub-Saharan Africa during the winter of 1996-97.
I'd also like to mention CDC's work in regard to surveillance and response to a few specific
diseases, including influenza -- a disease that has recently been on our minds and in the news.
Over the past year, CDC has augmented its international influenza network by increasing the
number of surveillance sites in China from 6 to 12, and by training laboratorians from 14
countries in Latin America and the Caribbean. It has also provided resources for enhanced
influenza surveillance in Russia. In addition, CDC has worked with the Pan American Health
Organization to provide training in the diagnosis of influenza and dengue hemorrhagic fever to
support active surveillance for these diseases in the Americas. CDC has played a major role
in the development and distribution of reagents through the WHO network for diagnosis and
surveillance of the new strain of influenza identified in Hong Kong. In conjunction with
WHO, CDC has also provided leadership in the development of a protocol for enhanced
surveillance for this new strain.
Outbreak Response
One of our most effective weapons against emerging and re-emerging diseases is an effective
international disease surveillance system backed up by the capacity to investigate and control
outbreaks of a variety of health problems in a timely manner. CDC continues to assist WHO and
foreign governments in responding to outbreaks of diseases that have high fatality rates or the
potential for international spread, such as the outbreak of a new and virulent strain of avian flu in
Hong Kong last fall and current investigations of Rift Valley Fever in Kenya and leptospirosis in
Peru and Ecuador. CDC's assistance may also be requested when the cause of an outbreak is
unknown, or when it involves a highly dangerous microbe that must be handled under the most
stringent biocontainment conditions -- like Ebola virus.
In August 1991, the first outbreak of cholera associated with an imported commercial food
product occurred in this country among persons attending a private picnic. An epidemiologic
investigation by CDC showed infection was associated with consumption of coconut milk
imported from Thailand. Working with the CDC and the Maryland Department of Health, the
CDC-sponsored Thai Field Epidemiology Training Program conducted an on-site investigation
of the production facility of the implicated coconut milk in Thailand. This investigation showed
several sanitary violations, suggesting that contamination had occurred during production. This
outbreak shows the linkage between domestic and international public health problems and how
CDC is working in partnership with other countries to build investigative capabilities.
Capacity-building
As evident from the above example, one of CDC's priority activities is, in partnership with
USAID, building the capacity in other countries to identify and respond to infectious diseases by
strengthening the human and technical infrastructure. Over the past 50 years, CDC has
contributed to the international supply of highly skilled public health practitioners through
several programs. Perhaps the best known of these programs is the Field Epidemic Training
Program (FETP). This is a 2-year training program that is modeled on CDC's domestic
Epidemiologic Intelligence Service (EIS). To date, CDC has sponsored FETPs in 17 countries.
These programs are designed for health professionals in entry- or mid-level positions and are
intended to assist in building capacity in the areas of applied epidemiology and enhanced public
health practice. In addition, CDC has worked with the Rockefeller Foundation to establish
Public Health Schools Without Walls (PHSWOW) programs in a number of other countries;
these programs also provide long-term training in both the principles and practice of public
health science. This innovative 2-year course of study in PHSWOW combines the strengths of
CDC's field training-through-service approach and the more traditional academic training
provided by schools of public health. In their individual countries the staff and trainees of FETP
and PHSWOW have already substantially improved both their national surveillance systems and
their responses to public health threats. CDC is actively working with WHO, the FETPs, and the
PHSWOWs in 15 countries to establish a network for global surveillance, outbreak investigation,
and training.
Other critical efforts to build capacity focus on strengthening laboratories to rapidly identify new
diseases and building health information and communication systems in order to collect and
disseminate information. CDC has an ongoing training program to transfer safe and simple
laboratory methods to developing countries and has developed innovative and low cost
computer-based tools to rapidly share information. The Epi Info program developed by CDC is
now the global standard for the collection and analysis of epidemiologic data.
Disease Eradication
I mentioned earlier CDC's leadership role in the global prevention of vaccine-preventable
diseases, beginning with the historic effort that culminated in the eradication of smallpox in
1977. In addition to the unprecedented humanitarian benefits, the financial benefits were
substantial. U.S. participation turned out to be a remarkably good economic investment. A total
of $32 million was spent by the U.S. over a 10-year period for the global campaign. This entire
sum has been recouped by the U.S., in 1968 dollars, every 2 1/2 months since 1971. This is the
amount saved because we have been able to halt routine smallpox vaccination, eliminating the
complications of smallpox, reducing foreign quarantine needs and eliminating requirements for
vaccination on entry to the country.
In 1988, the World Health Assembly resolved to eradicate polio by the year 2000. Extraordinary
progress continues to occur, including a 90% decrease in reported polio cases since 1988,
suggesting that the current strategies are effective and that achievement of the objective by the
year 2000 is feasible. However, acceleration and intensification of polio eradication activities
will be required, particularly in war-torn countries.
Collaboration among Rotary International, UNICEF, WHO, USAID, Japan, the Task Force for
Child Survival and Development, other international agencies, and CDC continues to strengthen.
This collaboration is unique among public health initiatives for the unprecedented level of
collaboration, the scale of private sector contributions, and the amount of funds raised. It is
estimated that Rotary International alone will have contributed $400 million (U.S. dollars) by
2005.
The underserved areas of developing countries that present the greatest challenges for disease
eradication are often the same areas where surveillance and response to emerging diseases are
most difficult. Therefore, infrastructure developed for disease eradication programs is an
extremely important byproduct of disease eradication campaigns. Eradication programs provide
tremendous training opportunities for epidemiologists, public health advisors, laboratorians, and
village health workers. Furthermore, as diseases are conquered, the resources used to address
them can be applied to new threats.
Applied Research
Over the past 50 years, CDC has established an outstanding tradition in the conduct of public
health research, with major benefits for the American people and other countries. Through its
applied research, CDC has helped to identify infectious disease agents, develop new diagnostic
tools, identify population groups at high risk, and evaluate the effectiveness of disease control
interventions. Our focus is on rapidly sharing research findings with other public health workers
in the field.
One of the areas in which CDC continues to make major research contributions is in the field of
HIV/AIDS. Worldwide, it is estimated that more than 1 million children have been infected with
HIV through mother-to-infant (perinatal) transmission. WHO projects that without an effective
and feasible preventive therapy, during this decade alone, 5-10 million children will become
infected with HIV through perinatal transmission, the vast majority in the developing world.
Since 1995, CDC has worked closely with public health authorities abroad to design and evaluate
a preventive therapy feasible to implement in developing nations. On February 18, 1998, CDC
was pleased to release preliminary findings from one of these collaborative clinical trials that
demonstrated that a short course of AZT therapy given late in pregnancy and during delivery
reduced the rate of HIV transmission of infants to infected mothers by 50% and is safe to use in
the developing world. The international community now faces the challenges of making this
prevention opportunity a reality for HIV-infected woman worldwide. The remarkable news is
that we begin with the first conclusive evidence that simpler, practical therapies can make a
difference.
Another area in which CDC's global health research activities have helped improve the health of
American citizens involves tuberculosis. In 1996, 37% of all new TB cases in the U.S. were
among foreign-born persons, representing a large increase from the 22% who were foreign-born
in 1986, when CDC first began collecting data on place of birth of its TB cases. Two-thirds of
the cases are from just seven countries: Mexico accounts for nearly a quarter of the cases, with
the Philippines and Vietnam accounting for an additional 14% and 11% respectively; India,
China, Korea, and Haiti each account for an additional 3-5%. In Mexico, a study done in
collaboration with local authorities revealed that most TB cases among foreign born patients
living in the U.S. occur among longtime U.S. residents and that frequent travel to Mexico is a
risk factor. Intervention strategies focused on this group of patients are now being developed.
Finally, CDC research has played a major role in better understanding hepatitis C infection,
which affects 170 million persons worldwide. CDC investigators helped to identify the hepatitis
C virus and demonstrate that chronic infection with that virus is a cause of death and serious liver
disease. These researchers also developed the diagnostic test for the virus. We can apply these
same skills to identify new diseases of global importance.
Future Plans
To fill gaps in the global capacity to address emerging diseases, as resources become available,
CDC proposes to intensify its efforts in several areas. These include preventing antimicrobial
resistance, ensuring the worldwide availability of diagnostic tests, improving preparedness for
outbreak responses on a regional basis, improving disaster preparedness, and addressing
environmental health conditions that give rise to some of these emerging diseases.
CDC is in the process of updating its emerging infections plan, taking into account the new
discoveries and challenges of the past 4 years, and building on the experience, success, and
knowledge gained from implementing the 1994 plan.
Controlling the global emergence and spread of drug-resistant pathogens remains a major focus
for CDC and its partners. The urgency of this problem was underscored by 1997 reports from
physicians in Japan and the U.S. that some strains of Staphylococcus aureus, a common bacteria
that can cause serious illness, are developing resistance to vancomycin, which is the only
antibiotic that remains effective against them. CDC is currently working with WHO, the US-EU
Task Force on Communicable Diseases, and many other partners to establish systematic
antimicrobial resistance monitoring throughout the world.
CDC's 1994 plan recognized the need to review the procedures for the detection and containment
of infectious diseases imported into the United States. CDC has begun to implement a plan to
improve detection and control at U.S. ports of entry, to improve management of diseases in
refugee and migrant groups that enter the U.S., and to improve communication of health
information related to international travel.
In addition, CDC has helped create a Sentinel Network of Travel Medicine Clinics, called
GeoSentinel, has been formed to monitor diseases in travelers, [including schistosomiasis,
dengue, hepatitis, and persistent fever of unknown origin.] GeoSentinel involves 15 travel
medicine clinics in the United States, plus 7 more in other countries (2 in Australia, 1 each in
Germany, New Zealand, Canada, Nepal, and Switzerland). The data are analyzed by CDC and
used to develop travel advisories and recommendations for health care providers. In the future,
GeoSentinel may help track the spread of diseases from place to place when outbreaks occur.
CDC has been working with the Pan American Health Organization, Ministries of Health of
other countries and with private industry to develop and test a water vessel and disinfectant
intervention. A preliminary study showed that this intervention reduced diarrheal illness by
44%. With the support of the Rotary Club, Proctor and Gamble, Inc. and a local non-profit
organization, CDC is conducting a collaborative field trial in Bolivia. A previous field trial
supported by Proctor and Gamble, Inc., has been conducted in Guatemala. In conclusion, I hope,
Senator Frist, that you and Members of the Subcommittee now have a sense of the broad range of
CDC's leadership in global health activities. With the support of the American people and the
Congress, we have accomplished a great deal, but much remains to be done. The threats our
citizens face from emerging and re-emerging infectious diseases are serious and growing, and
CDC is committed to working with our partners in the public, private, and voluntary sectors to
meet these urgent threats. I will be happy to answer any questions you or other Members may
have. Thank you.