EPID: Focus on Surveillance
Emerging Infectious Diseases in the 21st Century:
A Threat to Global Economic Security**
Duane J. Gubler, Sc.D., M.S.
Professor and Director, Signature Research Program in Emerging Infectious Diseases
Duke-National University of Singapore Graduate Medical School
Director, Asia-Pacific Institute for Tropical Medicine and Infectious Diseases
John A. Burns School of Medicine, University of Hawaii
There has been a dramatic global re-emergence of epidemic infectious diseases in the past 30 years. In 2010, infectious diseases are once again a leading cause of morbidity and mortality in the world. The reasons for this re-emergence are many, but the principal drivers are uncontrolled urbanization, which has greatly increased infectious disease transmission, combined with the massive movement of people, animals, and commodities via modern transportation into areas that do not have the public health infrastructure to detect and contain introduced pathogens. This provides the ideal recipe for increased epidemic transmission of both well known and novel pathogens. The potential for rapid spread of epidemic disease around the world is a new phenomenon that threatens global economic and public health security.
Rare, unexpected plagues of epidemic infectious diseases have entered human history for centuries, with devastating consequences. After having effectively controlled most major infectious diseases in the mid-20th century, epidemic infectious diseases have returned with a vengeance. Moreover, the frequency of epidemics caused by newly emerging and re-emerging pathogens, and the likelihood of rapid global spread, have dramatically increased in the past three decades. This is illustrated by the emergence of pneumonic plague in India (1994), panzootic H5N1 influenza in Hong Kong (1997), Nipah encephalitis in Malaysia (1999), severe acute respiratory syndrome (SARS) in China (2003), and pandemic swine origin H1N1 influenza in Mexico (2009). A combination of global demographic, socioeconomic, environmental, and ecological trends have driven this dramatic re-emergence of epidemic infectious diseases in the past 30 years. These trends, along with continued globalization, are projected to continue for the indefinite future – making the world highly vulnerable to increased occurrences of epidemic infectious diseases that will threaten global economic security and public health.
The current reality is that few countries in the world, especially those resource-poor countries where most of these diseases will emerge in the future, have the laboratory and epidemiologic capacity and capability to address this threat. With few exceptions, most infectious pathogens are ignored until an epidemic occurs, at which time both local and international health agencies move into emergency response mode, which is almost always too little, and too late, to have any impact on transmission. This type of crisis mentality is very dangerous when dealing with highly transmissible pathogens that can move rapidly around the globe via modern transportation. Only two epidemics in modern history have shut down global commerce, both of them in the past 16 years. The first was the 1994 Indian epidemic of pneumonic plague, which was more an epidemic of panic than disease. The 2003 SARS epidemic was even more devastating, costing the global economy an estimated $60 billion to $100 billion (U.S.). Neither of these epidemics were major public health crises, but both threatened global economic and public health security by shutting down the airline network. Future epidemics, which will surely occur, will likely have an even greater economic impact. The 2009 H1N1 influenza pandemic had the potential to cause such chaos, as the virus was highly transmissible and spread around the world in just a few months. Fortunately, however, the illness associated with that virus was mild and did not cause the panic and alarm that a more virulent virus would have done. In summary, the current realities are that we are highly likely to see emerging infectious disease epidemics that threaten economic and public health security with increasing frequency in the next 20 years, but programs to prevent or decrease that threat are not being developed and effectively implemented.
Scientific challenges and opportunities
Challenges include: 1) To develop and implement proactive early warning disease detection systems that can detect, identify, and contain pathogens with epidemic potential before they spread too widely. It is projected by the United Nations (U.N.) that in the next 25 years most of the economic growth will be in Asia, which will drive increased population growth in the cities, caused primarily by a circular rural to urban migration of people from rural areas moving to the cities to seek work, but returning to their rural homes a few times a year to plant and harvest crops and visit family. This will increase the risk of exotic pathogens that have been infecting people for hundreds of years in rural areas being introduced into crowded Asian cities, where there is increased risk of epidemic transmission. The economic growth will also drive increased movement of people, animals, and commodities via modern transportation, which will increase the probability of rapid spread of pathogens to other parts of the world. 2) To prevent the spread of pathogens and arthropod vectors via modern transportation. This has important economic and political implications that have not been addressed by international health agencies. The main problem is the thousands of jet airplanes that move more than two billion people and hundreds of millions of animals of all kinds around the world annually. These people and animals are carrying infectious pathogens with them, increasing the probability of global spread. 3) To develop the political will and funding needed to support laboratory and epidemiologic capacity-building and technology transfer. This will require eliminating apathy among the public and policy makers. 4) The vast majority of emerging diseases will never have a drug, a vaccine, or therapeutic antibody that can be used for treatment and prevention. To effectively contain and prevent these diseases, we must study their ecology to better understand transmission dynamics.
Opportunities include: 1) Training scientists and transferring the latest technology to countries of the region. This will provide expertise and technology to develop a biomedical research base, leading to discovery of new drugs, vaccines, diagnostics, and other treatment modalities, thus providing an economic stimulus. 2) Developing better laboratory and epidemiologic capacity, and early warning disease detection systems, which will allow public health officials in countries where surveillance is implemented to better understand the etiology of the infectious illnesses in their countries. This will result in more effective containment, decreased transmission, and early treatment, thus saving lives, improving the overall public health, and increasing the productivity of the population in general. 3) Discovery of newly recognized pathogens will drive basic science research. This research activity will result in creation of new jobs and new commercial ventures.
Policy issues that must be dealt with to reverse the trend of globalization of epidemic infectious diseases include the following:
- The movement of pathogens and vectors via modern transportation. Dealing with this issue will have to be the responsibility of the World Health Organization (WHO), with backing from the World Health Assembly. Regulation and enforcement should be incorporated into the International Health Regulations.
- International cooperation and sharing of proactive surveillance data. This will require developing a secure network — using the latest information technology — to link local, country, regional and global health agencies in order to share real time specific data on disease incidence, location, and spread.
- Triggers to initiate local and international response to epidemic transmission. Emergency response plans are developed by public health officials, but implementation of the response depends on a political decision. Implementation triggers that are, to the extent possible, outside the political realm, must be built into the response plans to allow rapid and effective response.
- Developing regional surveillance and response programs as opposed to country programs. Effective control in one country is not possible if the rest of the countries in the region are experiencing high-level disease transmission. The WHO, in collaboration with the countries and international funding agencies, must develop and implement regional control programs.
- Capacity-building and technology transfer to improve early warning surveillance. Currently, clinical samples from an emerging pathogen must be sent to the U.S., Australia, or Europe for identification of the pathogen, resulting in valuable lost time in diagnosis. We need to build the capacity and transfer the technology to allow resource-poor countries — where the diseases are likely to emerge — to develop and implement active early warning disease detection systems sensitive enough to allow containment before the pathogen spreads too widely.
- Improved cooperation and coordination between human and animal health surveillance systems. The systems as currently managed run parallel to each other with little exchange of data. We need to develop collaborative field programs that are linked by the latest IT systems to share real-time data.
- Emphasis on prevention and containment as opposed to emergency response. We are a crisis-oriented society; we do not do anything to prevent most diseases, rather waiting until an epidemic occurs and then trying to respond. We need to emphasize preventive medicine more and stop putting all the emphasis on curative medicine.
- Responsibility of the private sector. We need to harness the private sector resources and expertise to help fund the types of programs that will prevent epidemics that threaten global economic security.
** A policy position paper prepared for presentation at the conference on Emerging and Persistent Infectious Diseases (EPID): Focus on Surveillance convened by the Institute on Science for Global Policy (ISGP) Oct. 17-20, 2010, at Airlie Conference Center, Warrenton, Va.
The following summary is based on notes recorded by the ISGP staff during the not-for-attribution debate of the policy position paper prepared by Dr. Duane Gubler (see above). Dr. Gubler initiated the debate with a 5-minute statement of his views and then actively engaged the conference participants, including other authors, throughout the remainder of the 90-minute period. This Debate Summary represents the ISGP’s best effort to accurately capture the comments offered and questions posed by all participants, as well as those responses made by Dr. Gubler. Given the not-for-attribution format of the debate, the views comprising this summary do not necessarily represent the views of Dr. Gubler, as evidenced by his policy position paper. Rather, it is, and should be read as, an overview of the areas of agreement and disagreement that emerged from all those participating in the critical debate.
- Developing drugs and vaccines for the majority of infectious diseases requires additional information that can only be provided by enhancing disease monitoring and laboratory-based surveillance.
- For those infectious diseases where no clear pathways for developing drugs or vaccines exist, public health prevention initiatives must be expanded (e.g., the use of mosquito nets for malaria).
- Public-private partnerships must be strengthened to stimulate drug/vaccine research into the control and treatment of infectious diseases that would not otherwise be considered economically feasible. The private sector’s role in the surveillance and mitigation of infectious diseases should also be widened since its engagement not only increases the economic viability of how infectious diseases are addressed, but also provides lessons in efficiency.
- Recognition of the importance of animal-to-human transmission necessitates better coordination and integration of infectious disease surveillance involving animals and humans.
- In recognition of finite human and financial resources, it is increasingly important to consider the priorities used to determine how these resources are allocated to specific geographic regions. While Asia is expected to bear a comparably larger disease burden, resources focused on infectious diseases are currently concentrated in Africa.
- Given the critical role played by all forms of transportation (especially air travel) in the transmission of infectious diseases, monitoring the health of travelers is an important component in the design of sentinel surveillance systems. Serious concerns regarding publicly acceptable levels of privacy and pre- and post- travel screening (including the choice of screening technologies) are major issues.
- Responsible government officials need to be well informed by the credible scientific community. In turn, these officials are responsible for conveying accurate information concerning infectious diseases, including the relative risks, to the public. Communication skills among public officials and scientists must be significantly improved to facilitate both processes and thereby, to gain the public trust needed to implement effective disease control.
- A redistribution of responsibilities among international, national, and local authorities responsible for infectious disease surveillance is urgently needed. While local ownership of and responsibility for infectious disease surveillance should be emphasized, especially in less-wealthy countries, any redistribution of responsibilities must be balanced against the increasing concerns over biosovereignty.
- To create an effective surveillance system for the protection of the public’s health, it is critical that infectious disease surveillance data be more effectively shared across national borders and throughout geographical regions.
Although much attention has been devoted to drug and vaccine research, it is unlikely that drugs or vaccines will ever be produced for approximately 90 percent of the known pathogens. Two principal rationales have been cited as the causes of this disparity. First, the production of drugs and vaccines for the majority of infectious diseases is not economically profitable. Thus, there is little incentive for private research investment into drugs and vaccines for these pathogens. Second, from a microbiological perspective, not enough is known to support the production of drugs or vaccines for innumerable infectious diseases caused by novel pathogens (e.g., SARS).
The expansion of modern transportation systems in recent decades has dramatically accelerated the movement of people, animals, and commodities across borders. This amplified movement — particularly via air travel — has acted as an efficient conduit for the spread of foodborne, vectorborne, zoonotic, and other types of infectious diseases through the transfer of pathogens among people who historically have had only modest contact with one another.
Urbanization and migration (primarily from rural areas to cities, but also circular migration whereby individuals oscillate between the two geographies) are both increasing at rapid rates. The United Nations (U.N.) projects that 80 percent of urban growth between 2000 and 2030 is expected to occur throughout Africa and Asia, but in the same period much of the economic growth will be in Asia. These trends will further stimulate population growth in cities. This increases the risk of exotic pathogens from rural areas being introduced into crowded urban areas under conditions that promote epidemic transmission.
It was generally concluded, from both scientific and policy perspectives, that international organizations such as the U.N. and the World Health Organization (WHO) have been largely ineffectual in leading global surveillance efforts needed to combat these trends.
During the past two decades, funding and resources for emerging infectious disease control (including surveillance) have predominately been concentrated in Africa. Despite this substantial investment, emerging infectious diseases remain a debilitating problem on the African continent. Asia, by contrast, has received significantly less financial support although Asia bears a comparably larger infectious disease burden. Unique ecological factors found in Asia were cited as reasons that future infectious diseases are likely to originate on that continent, especially those of zoonotic origin. It was suggested that most future infectious diseases causing the rapid movement of epidemics and significantly impacting regional and global economies are therefore likely to originate in Asia and be caused by viruses of zoonotic origin.
In the past 20 years, funding for infectious disease control has not been uniform across all world sectors. Wealthier nations have proven to be the most extensive investors in this issue, with the majority of their fiscal resources diverted to their own local initiatives or to Africa.
Country ownership of surveillance initiatives (i.e., the country acting as the principal driving force behind surveillance in terms of its design, goals, and implementation) is highly unusual in less-wealthy countries. Support from wealthier countries frequently results in their control over the strategies and plans used to implement surveillance programs, often leading to initiatives that are not well suited to the needs of a specific locale. The balance between the influence of wealthy and less-wealthy countries must be re-evaluated to support effective disease surveillance. Currently, less-wealthy countries depend on funding provided by international agencies that are tied to a specific disease (e.g., malaria or HIV/AIDS). As a result, agencies outside the affected country set priorities that may or may not be consistent with the needs of the targeted communities.
It was repeatedly mentioned that the public health community’s ability to effectively communicate convincing and cohesive messages to policy makers and the public is lacking. It was stressed that this deficiency not only undermines the public health community’s efforts to convey important information, but also engenders mistrust among the public and impedes political support for infectious disease control efforts such as surveillance.
Scientific opportunities and challenges
The reality that approximately 90 percent of pathogens will never have a drug or vaccine to combat their impacts was noted as an increasingly significant issue; the appearance of outbreaks and epidemics is significantly increased when there are no pharmaceutical treatments in place. As a consequence, the challenge of controlling emerging and persistent infectious diseases is intensified and new ways to tackle the problem are needed.
Human surveillance and animal surveillance typically occur in isolation of one another. Yet, transmission of infectious diseases from animals (both wild and domestic) to humans (i.e., zoonoses) is considered to be a major and increasingly important problem. The process of establishing sustainable mechanisms to develop coordination between these two surveillance realms is an important challenge requiring immediate attention.
Globally, hundreds of infectious diseases have been identified. However, there are also an undetermined number of unidentified infectious diseases. This is illustrated by the identification of more than 30 previously unknown diseases and viruses in the past three decades. The emergence of new and previously unknown infectious diseases poses significant challenges in terms of the design and implementation of strategies for their identification and control. The development and deployment of new, broad-spectrum systems designed to provide the rapid genomic identification of diseases is critical to support modern surveillance systems. These systems can better facilitate the timely decisions needed to control outbreaks, prevent the spread of disease, determine the proper allocation of resources, and adjust disease control programs to effectively protect human health.
Although wealthier nations have developed reasonably strong surveillance capacities, the same is not true among less-wealthy nations. Two issues are of prime concern: the sustainability of surveillance programs and the breadth/quality of laboratory capacity. Both require focused attention in the near future.
The rapid spread of infectious diseases via modern modes of transportation creates logistical problems and raises questions within ethical spheres. Not only does the movement of people and pathogens within a globalizing world increase the probability of transmission and spread — a significant public health and economic challenge in and of itself — but it also is complicated by the logistical detection of disease at border crossings and raises many privacy concerns through practices such as airport screening. Ways to successfully combat these barriers are needed, but are complicated by economic concerns. For example, two recent epidemics (plague in 1994 and SARS in 2003) caused substantial interference to the global airline industry. This resulted in an enormous financial drain on the world economy.
The challenges created by the absence of drugs and vaccines for the majority of infectious diseases were highlighted as issues that require multiple, creative solutions. First, an expansion in the role of prevention and monitoring, including epidemiological studies, is needed to rapidly stem outbreaks via other traditional public health measures, such as hygiene and sanitation. In addition, the number of diseases that lack pharmaceutical interventions could potentially be reduced through more aggressive public-private partnerships. In particular, partnerships that increase research into drugs or vaccines for diseases that would otherwise not be considered by the private sector alone (due primarily to commercial concerns) are of great value.
Despite an enormous investment in funding infectious disease control within Africa during the past two decades, there was concern expressed over how effective these resources have been in controlling infectious diseases in general. There was considerable discussion of a proposal to allocate more resources for disease surveillance to Asia, even under circumstances that required diverting these types of resources away from Africa. A variety of explanations and reasons motivating changing the priorities for resources from Africa to Asia were given including: (i) the presence of confusing and disruptive political and economic pressures in Africa that have led to a poor return on investment of funds devoted to a given region, (ii) the increasingly rapid urbanization and economic growth in Asia that can be expected to cause significant increases in the outbreak and spread of infectious diseases in populated areas and the increased need to commit substantially larger resources to surveillance, containment, and control activities, and (iii) the prediction that most new diseases threatening the security of regional and global economies will originate in Asia and be caused largely by zoonotic viruses.
While the potential importance of these reasons was acknowledged and the value of increased investments in disease surveillance in Asia recognized, there was no consensus that shifting financial and human resources now devoted to disease surveillance in Africa to Asia could be supported. The principal reasoning opposing such an Africa-to-Asia shift centered on the widely recognized severity of the current and expected disease burden in Africa. There was strong support for increasing the overall resources to permit more to be sent to Asia while at least maintaining current levels in Africa.
The increased probability of spreading infectious diseases via modern transportation mechanisms raised complex issues. Nonetheless, it was generally agreed that properly controlling the impact of transportation on infectious disease spread must be addressed despite the potential introduction of significant social, political, and economic problems. Several potential solutions were suggested for managing the intersection of travel and spread of disease including: (i) sentinel surveillance systems in airports, (ii) prescreening prior to travel in high known-disease incidence countries, (iii) health monitoring as a follow-up in the destination country, (iv) widespread enforcement of the WHO International Health Regulations, and (v) expanded basic research into new approaches to monitoring the health of travelers during their journeys. Major concerns were expressed about the use of airport screening, which was deemed in some cases as an unacceptable infringement on personal liberties. It was unanimously concluded that experience had shown that temperature scans in airports were ineffective. In spite of specific concerns, there was consensus on the need to immediately implement a variety of new, practical measures to reconcile increased travel with obtaining accurate surveillance data.
One dissenting opinion focused on the view that travel did not increase infectious disease risk and that if travelers feel their access to transportation is threatened, they will withhold the information essential to accurate surveillance.
The public’s distrust of scientific data and predictions, especially in conveying the degree of risk involved with infectious diseases, was universally cited as an enormous problem requiring decisive actions aimed at re-establishing the public’s confidence in scientific reasoning. It was also collectively asserted that the scientific and public health communities must learn how to more effectively convey information within public, political, and media spheres without providing inappropriately conflicting information that confuses these sectors. Specific methods for achieving these goals were not evident. Disagreement was expressed concerning precisely what information, and therefore the degree of understanding, the public and policy makers want. Some saw great value in exploring what information the public would accept from health officials, while others felt that public health messaging should be based strictly on issues identified within the health communities, irrespective of public and political desires.
Considerable agreement was found concerning the role of local institutions in the ownership of strategies and programs used in the surveillance of emerging and persistent infectious diseases. While it was unanimously concluded that a more bottom-up development of a country’s role in designing and implementing surveillance systems is needed to identify the priorities for data collection and to create sustainable surveillance systems, it was also noted that promoting the sharing of the resultant information is an essential part of the global value of the data.
Although country ownership was deemed critical, there were consistent calls for increased global leadership in infectious disease surveillance. Reasons for this were cited as: (i) the impact of a rapidly globalizing world, (ii) the need for regional networks, which require top-down guidance, (iii) the role of travel in infectious disease transmission, which displaces national agendas, (iv) and the importance of standardized information. While the need for global leadership was not disputed, no consensus was reached on which international body should take the lead in these matters (e.g., the U.N. versus the WHO) and there was concern over how to convince countries to work together through international organizations.
It was noted that the programs for disease surveillance in humans and animals are not well connected. The two systems generally run parallel to one another without much coordination or communication. While there was agreement that greater interface is needed between the two, the discussion concerning what practical solutions should be pursued reached no specific conclusions. There was clear agreement that the intersection of human and animal surveillance deserves a more extensive debate that focuses on specific next steps. Nonetheless, it was widely suggested that countries should adopt the “One Health” approach focused on greater information sharing between human and animal health experts, as well as cooperative efforts to identify and prevent infectious diseases that can cross species barriers.
While data collection is the natural focal point of surveillance, data exchanges and sharing — particularly across country borders — both remain significant obstacles that threaten coordinated infectious disease control. A second major barrier is the lack of laboratory support for surveillance. While there was general consensus that data should be more effectively and extensively shared, there was disagreement on how to better develop data exchanges and on how much data can and should be shared. Suggestions for improving this problem included: (i) fostering better linkages of surveillance systems through leveraging the Internet (e.g., systems such as ARBONET), (ii) enhancing the interoperability of data, and (iii) encouraging a mindset shift on data ownership issues among the countries involved in the initial surveillance. Unresolved barriers included privacy concerns, data ownership issues (e.g., political, security, and economic), and assurance of scientific accuracy.
Capacity building for infectious disease surveillance was considered an essential activity, and specific recommendations were made for amplified laboratory support (particularly in less-wealthy nations where laboratory networks are frequently subpar), increased epidemiological training and equipment support, and fostering regional networks. The development of internationally sustainable programs for all of these activities is essential as well. The major challenges were identified as those associated with the funding of surveillance systems, which should be fundamentally anticipatory but usually are reactionary. Without a crisis of international dimensions, it is difficult to establish and implement priorities for the reallocation of either financial or human resources toward disease surveillance.
Infectious diseases threaten commerce through channels such as impeding tourism, closing animal markets and therefore endangering food supplies, and restricting transportation for both humans and commodities. It would be mutually beneficial for the private sector to increase its role in infectious disease surveillance and control. It was widely agreed that global business communities are critical partners in addressing these issues and that an effort to bring these communities into the debate is critical. Public health and scientific communities need to join the private sector in publicly discussing and promoting cooperative efforts to combat infectious diseases, especially with respect to identifying specific roles for the private sector that are consistent with regulatory responsibilities. These public-private partnerships also can be anticipated to promote open discussions of disease risks that can bolster public trust in the subsequent decisions made during outbreaks and pandemics.
Copyright: Institute on Science for Global Policy