Feds: Rapidly emerging infections warrant global surveillance network

ICPs, epidemiologists key partners with public health in ambitious effort

Warning that infectious diseases are emerging worldwide, a multi-agency U.S. government task force is recommending sweeping improvements in domestic and international surveillance. Citing the ultimate goal of a global surveillance network, a recent report by the group concludes that current methods may not detect emerging infections within the United States or prevent rapid importation of even the most far-flung international outbreaks.1

The 54-page report was prepared by a government working group on emerging infectious diseases that was formed under the auspices of the National Science and Technology Council -- a cabinet-level group that includes U.S. Vice President Al Gore.

According to a statement by Gore included in the report, the administration "is committed to putting into place a national response to the growing threat of infectious diseases -- a response that involves a coordinated strategy of basic research, training, public health programs, foreign assistance and security measures. Internationally, the U.S. will work with multilateral organizations and other countries to improve worldwide disease surveillance, reporting and response, while encouraging other countries to make infectious disease detection and control national priorities. Our ultimate goal is to foster the creation of a worldwide surveillance and response network."

ICPs seen as major players in controlling emerging problems

Compiled by the council's Committee on International Science, Engineering, and Technology (CISET), the report included input from of the Centers for Disease Control and Prevention, the Department of State, the Food and Drug Administration, the National Institutes of Health, the Department of Defense, and many other federal agencies. The panel cited an unforeseen increase in emerging infections, resurgent diseases, and antibiotic-resistant pathogens in outlining an ambitious array of recommendations. (See tables and related stories, pp. 19, 21-23.) While many of the emerging pathogens are more of a public health concern at present, infection control practitioners and hospital epidemiologists are seen as key partners in any domestic or international surveillance systems, says James Hughes, MD, director of the CDC Center for Infectious Diseases in Atlanta and one of the principal CDC representatives in the effort.

"Anybody working in hospital infection control is going to be in a position to hear about community-acquired organisms that may represent emerging and re-emerging infection problems," he tells Hospital Infection Control. "They may not be asked to address them if there is not much potential for nosocomial transmission, but because of their expertise in infection control generally and their role in the hospital, they are likely to be aware of such episodes -- clusters of patients admitted with a similar syndrome. I see the infection control people really as partners with people in local and state health departments in identifying and addressing these issues. It is no secret that communication is often not what it might be and collaboration is not what it could be between those groups. [ICPs and epidemiologists] are ideally placed to help bridge this gap between the traditional public health people and the clinicians."

Distant shores or within your doors

Underscoring that ICPs must fill critical roles as educators on the issue, the Dade County, FL, chapter of the Association for Professionals in Infection Control and Epidemiology (APIC) was planning a one-day seminar for health care workers on the "global war" against emerging pathogens for Feb. 2, 1996, in Miami. The seminar was being held to educate workers and clinicians in all medical fields about the burgeoning trend -- and reassure them that nosocomial transmission can be prevented even if patients with emerging pathogens are admitted, says one of the organizers, Jackie Moore, RN, BS, nurse epidemiologist at Mount Sinai Medical Center in Miami.

"We are very concerned with the emergence of resistant organisms, not to mention all of the emerging infectious diseases which could very easily come to our continent by air travel," she tells Hospital Infection Control. "We really need to know more about these diseases and be prepared if they come into our hospitals. Can you imagine the panic if an Ebola patient came into a hospital? We take very seriously the direction from the CDC that we all need to get out there and start educating our health care workers about resistant organisms and emerging pathogens. Who else is going do the education?"

Noting that most American cities can be reached within 36 hours from anywhere in the world, either by direct or connecting flights, the government report reminds that the incubation periods for most infectious diseases are considerably longer than that. Such concerns were underscored last year when the CDC moved rapidly to issue hospital infection control guidelines for Ebola virus, in case U.S. facilities began admitting patients infected in an outbreak in Zaire. (See Hospital Infection Control, August 1995, pp. 101-103.) Though such a response in the United States to an outbreak thousands of miles away may have been surprising to some, it underscored real concerns in a new era of emerging infections.

"Though we did not have any importations, people recognized that the threat was real -- more real than in the 1970s when we had the last large Ebola outbreak," says William Schaffner, MD, chairman of the department of preventive medicine at Vanderbilt University School of Medicine in Nashville. "The world is so much smaller today -- so many people travel so far so quickly. It was not at all unreasonable to imagine somebody getting on a plane somewhere in Central Africa carrying the virus and winding up within the incubation period somewhere in the interior of the United States."

'Superbugs' coming your way

On the other hand, emerging pathogens need not arrive from distant shores. The CDC expects the much-discussed, theoretical "superbug" vancomycin-resistant Staphylococcus aureus (VRSA) to appear first in a clinical setting. Indeed, the antibiotic-resistant element of emerging infectious disease has long been associated with hospital infection control.

"The big impetus for developing hospital infection control programs in this country came from the penicillin-resistant staphylococcal pandemic that swept around the world in the late 1950s and early 1960s," Schaffner notes. "So the major emphasis at the CDC and within hospitals on infection control was born out of an emerging infection that became a global pandemic. That's the history of our birth."

In addition, diseases like tuberculosis -- particularly drug-resistant strains -- have provided another example in recent years of a how resurgence in the community can lead to widespread infection control problems in hospitals, adds William Jarvis, MD, chief of the investigations and prevention branch in the CDC hospital infections program.

"People should recognize that many of these organisms may not have been a problem in the past in a hospital in the United States, or in their particular area, but may be in the future," he says.

For example, group A Streptococcus has re-emerged in particularly virulent strains that can cause severe, life-threatening infections in both community and hospital outbreaks. (See related story, p. 23.) In addition, drug-resistant Streptococcus pneumoniae (DRSP) has increased rapidly as a community-acquired infection in the United States, but has been the source of nosocomial outbreaks in Europe.

"The same thing could certainly could happen here," Jarvis warns.

Indeed, the CDC is assisting in investigating a DRSP outbreak in Mexico City that includes nosocomial cases, says Martin Cetron, MD, medical epidemiologist in the CDC childhood and respiratory diseases branch.

"In Mexico, we found that in reviewing the invasive [DRSP] cases in a tertiary care referral hospital, there were more nosocomial drug-resistant cases of invasive disease than we traditionally see in the United States," he says. "So it could be that in the developing world, where kids are brought together for the first time on a pediatric ward, that may be the right environment [for transmission] -- that is the overlap of a lot of antibiotic use and the sharing of a lot of respiratory secretions in children in close quarters. In the U.S., the major institution that seems to be fostering that spread is the day care center."

Complacency carries a high price

Though the reasons for the resurgence of infectious diseases are not fully understood, the CISET report cites such factors as the "extraordinary resilience" of infectious microbes, particularly their ability to develop drug resistance. A less scientific explanation -- complacency -- was also implicated as a key factor in both the dramatic return of TB and the emergence of the AIDS epidemic.

The panel cited TB and AIDS as diseases that flourished under prevailing conditions of complacency caused in part by the belief that the threat of infectious diseases appeared to be receding. TB re-emerged in the United States in the late 1980s, for example, after government spending on infectious disease control declined and surveillance for drug-resistant TB was discontinued. By 1993, multidrug-resistant TB had became a public health crisis, and millions of federal dollars were necessary to control the emergency, the panel reminded. Likewise, when the first cases of AIDS and drug-resistant TB were detected in the United States, control measures were delayed, partly due to a lack of surveillance information. Indeed, AIDS might have been identified before it became established in the United States if a global surveillance system with the capacity to identify new diseases had been in place in the 1970s, the CISET report states.

Getting a head start on new problems

"As early as 1962, African doctors apparently witnessed cases of what was then known as 'slim disease,'" the report states. "Had the international community taken notice, epidemiologists might have gained a head start in learning how AIDS is transmitted and prevented, and many lives might have been saved."

Noting that diseases that arise in other parts of the world are repeatedly introduced into the United States and threaten national health and security, the report goes on to raise the specter of terrorism and biological weapons.

"An effective global disease surveillance and response network will enable the United States to respond quickly and effectively in the event of terrorist incidents involving biological or chemical agents," the CISET report states. "The experience gained in controlling naturally occurring microbes will enhance our ability to cope with a biological warfare agent, should the need arise. The release of nerve gas in the Tokyo subway system in March 1995 has underscored our need to be well prepared to counteract deliberate attempts to undermine human health."

The elements of a global network for disease surveillance already exist but need to be strengthened, linked, and coordinated. Many U.S. government departments and agencies maintain or support field stations and laboratories in Africa, Asia, and the Americas that may be electronically linked to provide an initial framework for a network for global infectious disease reporting, the panel notes. In partnership with other countries and with the World Health Organization in Geneva, that skeletal surveillance network could be expanded over time to include many international resources, including national health ministries, hospitals, and laboratories operated by other nations.

Lack of money 'cripples' U.S. efforts

While efforts to expand global surveillance are under way, the national surveillance program in the United States remains "crippled" by inadequate funding to detect emerging infectious diseases, the report states. The national surveillance system for notifiable diseases has long provided the basis for the system, but state and local support for infectious disease surveillance has diminished.

"As a result, many of the currently reportable diseases are in fact significantly under reported, and in many areas there is limited follow up of the cases that are reported," the CISET working group found. "Moreover, public health agencies are reluctant to add new diseases to the list of notifiable diseases because their capacity to support the surveillance system is already limited by lack of funds and personnel. . . . At the current level of disease surveillance, it may take hundreds of cases before an outbreak of a non-targeted disease in a large urban area will be detected."

The panel recommended shoring up the national notifiable disease system while establishing sentinel surveillance networks to detect and investigate newly emerging diseases. The CDC has established the first four Emerging Infections Program sites, but funding remains in question to preserve the existing program, as well as to complete a planned expansion to 10 sites. (See Hospital Infection Control, March 1995, pp. 29-32; October 1995, pp. 131-133.)

"We are going to do everything we can to maintain those four sites," Hughes says. "We would love to increase the activities of those four sites and add a couple more, but we can't do anything new until we see how the budget process plays out."

Money, politics are critical factors

Indeed, the issues of funding and the political will to meet the threat of infectious diseases remain the critical questions if any of the ambitious surveillance plans are to be realized. Among the immediate plans, the CISET panel urged establishing an interagency task force to coordinate the implementation of its recommendations. A proposed private-sector subcommittee of the task force would include representatives of the pharmaceutical industry, medical practitioners and educators, and biomedical scientists. A factor that may influence the process is that both the public and politicians may have become more attuned to the issue of infectious diseases, which have been increasingly reported and fictionalized in recent books and films of popular culture.

"I think people understand better than they did three years ago the challenges that infectious diseases are continuing to pose," Hughes says. "They are becoming convinced that the complacency we have repeatedly demonstrated and practiced in the past is a bad idea and we paid a price for it. I think people on both sides of the aisle [in Congress] are beginning to see that, [and] the public is more knowledgeable."


1. National Science and Technology Council. Committee on International Science, Engineering, and Technology. Working group on emerging and re-emerging infectious diseases. Infectious Disease -- A Global Health Threat. Washington, DC; 1995. *