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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary 2 Surveillance Networks OVERVIEW As several of the contributors to this chapter note, clinical surveillance of infectious disease is inadequate in much of the developing world due to limited funding for public health infrastructure. Because many impoverished regions are also at high risk for emerging disease threats, alternative methods of surveillance are crucial to global health. The papers collected in this chapter describe a variety of electronic surveillance networks, designed to gather and integrate information on infectious disease from a variety of nontraditional sources (e.g., Internet sites, news outlets, observers with little or no medical training) and to disseminate alerts broadly and rapidly. The chapter begins with a description of the first infectious disease surveillance network, ProMED-mail. Stephen Morse, one of the network’s founding members, provides a brief history of the free, nonprofit, noncommercial, moderated e-mail list that today serves over 37,000 subscribers in more than 150 countries, as well as anyone with Internet access. Since it began as an experimental system in 1993, ProMED-mail has helped to demonstrate the power of networks and the feasibility of designing effective, low-cost global reporting systems. It has also encouraged the development of additional electronic surveillance networks—such as the Global Public Health Information Network (GPHIN) and HealthMap, described in subsequent contributions to this chapter—and the World Health Organization’s (WHO’s) “network of networks,” the Global Outbreak Alert and Response Network, or GOARN (see Summary and Assessment). The chapter’s second paper, by presenter Abla Mawadeku and coauthors from GPHIN, offers descriptive comparisons of that network along with ProMED-mail
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary and the European Commission’s Medical Intelligence System (MedISys), which is available only to European Union member states. GPHIN, a primary source of electronic surveillance for WHO, also serves a host of government institutions, nongovernmental agencies and organizations, academic institutions, and private companies, who pay between 30,000 and 200,000 Canadian dollars per year in subscription fees, depending on the specific services provided. HealthMap is a freely accessible, automated network that collects information from multiple web-based data sources on infectious outbreaks (currently news wires, Really Simple Syndication (RSS) feeds, ProMED mailing lists, and EuroSurveillance and WHO alerts). The network then organizes and displays this information in real time as graphic “maps” featuring geography, time, and infectious disease agent. In their contribution to this chapter, workshop presenter John Brownstein of Harvard Medical School and his colleagues at Children’s Hospital Boston discuss their efforts to evaluate the HealthMap system with reference to four characteristics that have been used to evaluate syndromic surveillance systems: data acquisition; information characterization; signal interpretation; and dissemination. The authors’ preliminary evaluation of HealthMap according to these criteria appears to demonstrate that the aggregation of multiple sources of data—each potentially biased or otherwise flawed—increases the sensitivity and timeliness of alerts while reducing false alarms. The concluding paper of the chapter describes a different sort of electronic surveillance network: one powered by cell phones, enabling observers in some of the world’s most remote and impoverished communities to report disease outbreaks. The authors are workshop speakers Pamela Johnson of Voxiva, a company that provides information technology to establish surveillance networks in low-resource settings, and David Blazes, of the U.S. Naval Medical Research Center Detachment in Lima, Peru, which used an Internet- and cell phone-based electronic system developed by Voxiva to support disease surveillance by the Peruvian navy along that country’s coast and remote rivers. This experience is presented as a case study in surveillance and evaluated according to the Centers for Disease Control and Prevention (CDC) guidelines for public health surveillance systems. The authors also share lessons gleaned from six years of building surveillance systems, based on cell phones and other cost-effective information technologies, for use in low-resource environments. Workshop participants raised a series of issues in response to the presentations upon which the papers in this chapter are based. A detailed account of this discussion appears in the Summary and Assessment section, “Considerations for Surveillance Networks.” Discussants were especially concerned about the potentially devastating economic consequences to a country—particularly a developing country—of being labeled (accurately or inaccurately) as harboring a feared infectious disease. In his contribution to Chapter 4, speaker Will Hueston assesses the tradeoff between health and development inherent in the release of surveillance information such as HealthMap’s geographic depictions of outbreak reports.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary GLOBAL INFECTIOUS DISEASE SURVEILLANCE AND EARLY WARNING SYSTEMS: PROMED AND PROMED-MAIL Stephen S. Morse, Ph.D.1 Columbia University A number of emerging infections have appeared throughout the world in recent years (Morens et al., 2004; IOM, 1992, 2003; Morse, 1995). Or, in the words of Marci Layton (New York City Department of Health and Mental Hygiene), we must learn to expect the unexpected. It is widely agreed that one of the most important measures for both emerging and existing infectious diseases is an effective early warning system, that is to say, global infectious disease surveillance. Here, I will discuss ProMED, the nonprofit international Program for Monitoring Emerging Diseases, and its best known progeny, ProMED-mail (PMM). ProMED itself was founded in 1993 to design and help implement global surveillance systems that could detect both known and emerging infections (Morse et al., 1996). A Brief History of ProMED and ProMED-Mail ProMED had its roots in the same Institute of Medicine (IOM) report that led to the development of the Forum on Microbial Threats (IOM, 1992). The Committee that developed the 1992 IOM report was chaired by Joshua Lederberg and the late Robert E. Shope. After the report was released, there was considerable concern about maintaining the momentum. Many of the original Committee members (including me) believed the problem required long-term attention. In addition, for specific reasons the charge to the IOM Committee and consequently the report were limited to the United States. However, there was a clear need to consider these infections as global threats that would require international solutions. In an attempt to fill what many (including this author) saw as the fragmentation of disease surveillance systems and the lack of global capacity, ProMED was begun in 1993 under the auspices of the Federation of American Scientists (FAS).2 Several years earlier, I had been asked by Barbara Hatch Rosenberg, then chairing a working group on biological nonproliferation issues at FAS, to provide technical advice for her working group. After the 1989 National Institutes of Health (NIH) meeting on emerging viruses and the 1992 IOM report, Rosenberg and I discussed the possibility of developing an initiative for global infectious 1 Mailman School of Public Health. 2 An article on the early history and activities of ProMED is available at http://www.fas.org/faspir/pir1293.html, with an update at http://fas.org/promed/announce.htm. Additional materials are available at http://fas.org/promed/.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary disease surveillance, with start-up resources from FAS. Dorothy Preslar served as the project staff at FAS. The group held a small initial organizational meeting in February 1993 at The Rockefeller University in New York. In addition to Rosenberg, and myself as Chair, among those present at that meeting were Ruth Berkelman (then at the Centers for Disease Control and Prevention, or CDC), Scott Halstead (then at the Rockefeller Foundation), D. A. Henderson (then at Johns Hopkins and the U.S. Department of Health and Human Services), James M. Hughes (then at CDC), John LaMontagne (then at NIH’s National Institute of Allergy and Infectious Diseases, or NIAID), and Shope (then at Yale). At that time, it was decided that a conference would be held in Geneva in fall 1993, that the group’s purview should include animal and plant diseases in addition to human disease (a view especially advocated by Berkelman), and that the group should be named ProMED (Shope suggested the name). The next activity was a conference, cosponsored by FAS and the World Health Organization (WHO) and held on September 11 and 12, 1993, at WHO headquarters in Geneva. Part of the challenge at that time was that the then-Director General of WHO did not believe that surveillance for infectious diseases was part of the organization’s core responsibilities. Unfortunately, many clinicians and most of the lay public naïvely believed otherwise, and thought that WHO was already doing it. The September 1993 ProMED meeting, co-chaired by Francis Nkrumah of Ghana and myself, was held in the WHO Executive Board Room, and included as speakers a number of people who had been influential in WHO affairs, including Jan Kostrzewski, a former chair of the WHO Executive Board, Henderson, and a number of members of the World Health Assembly. At that event, 60 prominent scientists and public health officials working on human, animal, and plant health from all parts of the world met, unanimously endorsed the concept of global surveillance, and formed ongoing working groups to assess present capabilities and develop and implement plans for a suitable global program that could address both known and emerging infections. We also invited John P. (Jack) Woodall (then at WHO) onto the Steering Committee, and James LeDuc (then at WHO, seconded from CDC) agreed to serve as a special consultant.3 One would think it should be fairly simple to strengthen and network regional centers of excellence to augment official systems and develop mutual cooperation, whether through WHO (preferably) or through regional intergovernmental organizations. On the other hand, if diseases can emerge anywhere, how can one get early warning from literally everywhere? The latter seemed the harder task, so we decided to try tackling what everyone considered the easier one first. At meetings in Geneva and elsewhere, we recommended developing a coordinated 3 The list of the early Steering Committee members can be found at http://fas.org/promed/about/steering.html.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary system of regional centers and a minimum set of capabilities to identify and respond to unusual disease outbreaks. A plan was subsequently published (Morse et al., 1996), in part elaborating on the system Henderson had proposed at the 1989 NIH/NIAID meeting on emerging viruses (Henderson, 1993). The strategy developed was vigilance for unusual clinical presentations of special concern (e.g., encephalitis or acute respiratory distress with fever in adults); a minimum set of microbiological capabilities at each site to identify common diseases; and a system to refer unidentifiable samples to successively more sophisticated reference laboratories, through the network, for possible identification. The plan also included epidemiologic capacity, which could be provided rapidly through the network if needed (Morse et al., 1996). The effort continued with meetings at other places. At a Steering Committee meeting in June 1994 at Airlie House in Virginia, we realized that our members from all over the world had no reliable means to communicate with one another. Nkrumah of Ghana, for example, had a Telex, which in any major American city usually required a trip downtown to a special office building to send, but no fax machine. In Russia, they had fax machines but no fax paper because of a lack of money. We decided to try to put everyone on a common communications system. Charles Clements, then at a nonprofit organization called SatelLife, which specialized in inexpensive e-mail connections for remote and underserved areas through satellite radio links, had been invited to the meeting. I appointed Woodall as head of a new Communications Task Force. By the end of the meeting a plan had been developed to connect everyone by e-mail. SatelLife provided connectivity for places without e-mail connections, for example (at that time) in Africa, China, and Russia. The rest of us learned how to use the existing e-mail systems at our institutions (quite an ordeal in those days). Thus ProMED-mail was born. Although only about 10 years ago, it was another era technologically. As the system developed and people started using e-mail for communications, we realized it could also be used as an international outbreak reporting system. (So much for deferring those “more challenging” goals, such as how to get reports from everywhere.) Woodall and I served as the initial moderators (or “editors”), a time-consuming task. Woodall deserves tremendous credit for his dedication and enormous contributions to the subsequent development of the system. Since 1995, the system has been available on the Web,4 as well as by e-mail subscription. The partnership between ProMED and SatelLife continued fruitfully until 1999, when the ProMED reporting network was transferred to the International Society for Infectious Diseases (ISID), headquartered at Harvard’s Channing Laboratory in Boston. The communications network was renamed ProMED-mail, to distinguish it from other ProMED activities then underway. 4 See http://www.promedmail.org.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary ProMED-Mail: A Prototype Infectious Disease Reporting System Many people think of PMM as synonymous with ProMED, as it has taken on a robust life of its own. PMM was designed as an open reporting and discussion system. It is a nonprofit, noncommercial e-mail list that now has some 40,000 subscribers, with over 165 countries represented. Not all of them, of course, send in reports because the editors would be overwhelmed, but many subscribers do read the e-mails on a regular basis. Although numbers vary, incoming e-mails (roughly 100 a day) generate an average of 7 to 10 reports every day. The e-mail listserv is moderated, which means that messages coming in are first read by people with scientific or medical expertise. Originally this was Woodall and at times me until I left for government service in 1996. As the list grew, a number of other moderators were recruited in various specialty areas, and the system is fortunate to have a number of distinguished experts as moderators. In principle, subscribers send in reports and information. Rapporteurs take additional responsibility to report regularly in their own geographic or special interest areas. Rapporteurs report from Russia, China, and a number of other places as well as within the United States. When someone sends in a report from somewhere (one of the earliest reports of Ebola in Kikwit, Zaire, now the Democratic Republic of Congo, came from a medical missionary who had a radio e-mail link), the report is assigned by the editor-in-chief or someone acting in that capacity, to the appropriate moderators for editing and, if appropriate, posting to the list. The moderator reads the report for scientific plausibility. If the report looks credible, the moderator edits and formats as needed, probably adds comments to put the item in context, and send it out as a posting to the list. All subscribers are free to comment or add information after reading the posting. In addition to the full list, which includes outbreak reports and discussions on human, veterinary, and plant diseases, there are several sublists for those who want only certain parts of this information. It is possible to subscribe to the animal and plant disease lists separately. The human disease list includes both human and animal disease. This causes occasional complaints from physicians, but we have believed strongly from the beginning that it is essential to improve the connections between animal and human health. Justifying this is the fact that many emerging infections are zoonotic. Those who are interested in getting only the breaking news, without the ensuing discussion, can subscribe to the Emerging Disease Reports (EDR) sublist. I get EDR on my BlackBerry wireless device. In recent years sub-lists have been developed in Portuguese, Spanish, and Russian, and there is interest in developing other foreign language lists as well. Some of the regional reports of wide interest are translated into English. The PMM architecture is simple. Technically, the e-mails are 7-bit ASCII text, the most basic format. When the system was started in August 1994, people in developing countries had very limited bandwidth. It is amazing how much
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary this has changed in the past decade, with broadband Internet cafes now even in remote areas. The editors also search the Web and press reports, an increasingly important source of information. This strategy was originally adopted by GPHIN (the Canadian government’s Global Public Health Intelligence Network), which is described in another chapter. GPHIN was started in 1999 and is based largely on news sources from the Web. Unfortunately such material was not available when PMM was started. Since then, the explosive growth of the Web and of improved methods for searching have made such strategies very effective. Perhaps one of the most important value-added features of PMM is the distinguished and hard-working team of moderators or editors (for this chapter, I am using these two terms interchangeably). Although they are essentially volunteers, all are subject-matter experts. The moderators also have their own e-mail lists and personal networks for follow-up, which demonstrates the power of networking. Larry Madoff is the current editor-in-chief of PMM, while Woodall (now associate editor) remains as active and involved as ever. He has had a critical role in developing PMM into what it is today. Eduardo Gotuzzo, in addition to being a member of the IOM Forum, is Chair of the PMM Policy Committee. All this is probably obvious to anyone who has read PMM. Anyone can contribute; data come from clinicians (those proverbial astute clinicians in the field all over the world), public health officials and epidemiologists, lab scientists, or medical missionaries, but also journalists and interested laypeople. There was a concern initially that the method of obtaining data would give rise to many rumors that health authorities would then have to verify, expending valuable resources. This has not turned out to be a major problem. Of course, sometimes information is incorrect, but in general the reliability turns out to be more than 95 percent, according to figures that Madoff tabulated. However, PMM has developed several mechanisms to deal with the possibility of erroneous reports. One is personal follow-up by moderators. The moderators, experts in their fields and generally well connected, can use their own personal networks to try to get more information to include. Second, an uncertain report could also be posted as a request for information (RFI), an inquiry which is simply a way of asking people if they have more information they can contribute. Others on the network may also spontaneously add to or correct a posting if they have additional facts. Subsequently, WHO, in response to information from PMM and GPHIN, developed a very effective mechanism of its own, called the Outbreak Verification List. WHO sends this list out regularly to a limited group of public health officials and scientists to try to follow up on various outbreak reports. It is a sign of WHO’s increasing capacity and interest that the reports increasingly are coming from WHO’s own country and regional representatives. WHO has developed its own network of networks, the Global Outbreak Alert and Response Network (GOARN), which includes a number of formal and informal sources. It should
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary be noted that the situation at WHO has greatly improved in the last few years, thanks to the concerted efforts of a number of people, including James LeDuc in the early days, and notably David Heymann more recently. One particularly interesting aspect of a system like PMM is that it can be used to compare reports from a number of places. In addition to outbreak reporting, it provides the ability for people to recognize that what they are observing may be happening elsewhere, too. An initial report may encourage others to contribute local information that may help to estimate the extent and numbers of an infectious disease outbreak, and to monitor spread. One example was a 1995 outbreak of meningococcal meningitis occurring simultaneously in several states and in the United Kingdom. The outbreak became evident when the reports from various places appeared on PMM. PMM has been available on the Web since the Ebola outbreak of 1995 in Kikwit, when it partnered with and later incorporated an independent effort called “Outbreak.” As the Web itself grows, the website has had an increasing presence. If one prefers not to receive e-mail alerts, it is a simple matter just to search the website and read any of the reports. The Web archives include some of the earliest reports, such as the first reports of Ebola in Kikwit. Among other PMM “firsts” was Venezuelan equine encephalitis, coincidentally in Venezuela. It was originally denied by the government; when it was verified it led to the resignation of the health minister. West Nile virus in 1999 was another event PMM extensively covered. During this period, Ian Lipkin generously wrote in to offer reagents for people internationally. Other firsts include reports of H5N1 influenza in Indonesia in November 2003 and fatalities in China in 2005 attributed to Streptococcus suis. The first report of severe acute respiratory syndrome (SARS) that appeared on PMM was a rumor about an unusual outbreak in south China with unexplained deaths. Steve Cunnion picked this up, and information was posted on February 10, 2003. Shortly after that, China officially reported the disease, and WHO was able to release information officially. By that time, China reported 305 cases. SARS had actually been infecting people for at least several months (IOM, 2004). SARS then spread to Toronto, where it was originally called “atypical community-acquired pneumonia” and was reported on PMM. Madoff has tabulated the PMM disease reports over the past 10 years. Dengue, which is quite common, is one constant, as are a number of others. Many are known conditions, but at least 209 are not. Some will eventually be added to the known category. There have also been reports of CDC Category A agents, normally more closely associated with bioterrorism or biowarfare. However, anthrax exists naturally throughout the world in livestock. In developing countries, there may be thousands of cases of gastrointestinal anthrax from contaminated meat. More than 200 cases of anthrax in livestock were reported on PMM before the intentional anthrax attacks of fall 2001. Botulism and tularemia are also natu-
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary rally occurring diseases, which reminds us that many of the classic bioweapons, including the Category A agents, are zoonotic agents. PMM was developed as a prototype, and continues to evolve. There have been increasing efforts since then. GPHIN and WHO’s GOARN have already been mentioned. A later paper, by Pamela Johnson, will discuss Voxiva, which uses the power of networks with another technological base, the cell phone network. PMM has also elicited some kind comments. Henderson referred to CNN and PMM as the major sources of information for infectious diseases. Steven C. Joseph (formerly New York City Health Commissioner, Dean of the Minnesota School of Public Health, and Assistant Secretary of Defense for Health Affairs) referred to PMM as “the CNN of infectious diseases” (Personal communication, S. C. Joseph, June 1995). Perhaps the most intriguing characterization comes from Steven Johnson, in his book The Ghost Map, about cholera in Victorian London. A sentence in the book caught me by surprise as I was leafing through it: The popular ProMED-mail e-mail list offers a daily update on all the known disease outbreaks flaring up around the world, which surely makes it the most terrifying news source known to man (Johnson, 2006). For an infectious disease surveillance system, that seems high praise indeed. Since PMM was started as an experimental system more than a decade ago, it has helped to demonstrate the power of networks and the feasibility of designing widely distributed, low-cost reporting systems, and it has encouraged the development of additional systems using additional technologies. All these efforts help to begin building the heavily networked surveillance systems that will be needed to deal with threats in an increasingly globalized and unpredictable world. Acknowledgments Sincere thanks to Jack Woodall and Larry Madoff for their hard work and helpful discussions, and to all the editors/moderators and funders of ProMED-mail for their dedication and good work.5 Stephen S. Morse is supported by CDC cooperative agreements A1010-21/21, U90/CCU224241 (Centers for Public Health Preparedness), and U01/CI000442, the Arts & Letters Foundation, and by NIH/NIAID cooperative agreement 5U54AI057158 (Northeast Biodefense Center RCE). 5 A list of current PMM personnel is at http://www.promedmail.org; click on “Who’s Who.”
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary GLOBAL PUBLIC HEALTH SURVEILLANCE: THE ROLE OF NONTRADITIONAL SURVEILLANCE TOOLS Abla Mawudeku, M.P.H.6 Public Health Agency of Canada M. Ruben, M.D., Ph.D.7 Public Health Agency of Canada R. Lemay, B.Sc., M.B.A.8 Public Health Agency of Canada Introduction In a world deeply interconnected by traveling and trade, the spread of infectious agents is inevitable. Regions once isolated are now integrated into the global community and have the risk of being exposed to infectious agents that they previously were unexposed to, as well as sources of old and new agents, and even new pandemics. Therefore, there is global concern about surveillance and control of diseases (particularly infectious diseases) around the globe. Any global surveillance system has to overcome several challenges; basically, it requires a good system for communications to and from the field to get timely collection, analysis, and dissemination of data, and to be able to force political decisions and allocation of resources. However, susceptibility to infectious diseases and increased risks of infection are usually associated with poverty, and poverty is more frequent in those countries where epidemiological and laboratory surveillance is defective or nonexistent (Heymann and Rodier, 2001). In addition, while several countries, particularly in the Western world, have already national surveillance systems to monitor for potential public health threats, in many circumstances these systems are inadequate, fairly erratic, or too disease specific to identify new diseases early (Butler, 2006). Also, countries have been reluctant to report outbreaks due to the perception of a negative impact of such news on the country’s economy (trade and tourism). Public alarm, sometimes fueled by the press, has resulted in many occasions in important losses for the countries, which then try to hide or delay the recognition of the presence of human or animal diseases (Cash and Narasimhan, 2000). Nevertheless, the electronic era, in which press reports and the Internet keep societies informed and interconnected, have begun to break down all attempts of “secrecy.” Currently there is no comprehensive global public health surveillance system. The World Health Organization (WHO) is the only organization that has the mandate to monitor and respond to global public health threats, as established 6 Chief. 7 Scientist. 8 Senior Surveillance Officer.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary in the International Health Regulations (IHRs). WHO not only uses information gathered from traditional surveillance systems but also uses information from nontraditional surveillance systems to leverage in order to capture a more comprehensive outlook of the situation about potential public health threats occurring worldwide. The use of nontraditional surveillance systems has contributed to the improvement of epidemic intelligence used for the early detection of potential public health threats. This has enabled WHO and other public health organizations such as the European Center for Disease Control (ECDC) to better assess, investigate, and respond to events of concern (Figure 2-1). A revised version of these regulations, IHR 2005, will be implemented in June 2007. These new IHRs will strengthen WHO’s authority in surveillance and response because they include more demanding surveillance and response obligations and apply human rights principles to public health interventions (Baker and Fidler, 2006). The new regulations require that member countries report to FIGURE 2-1 Epidemic intelligence framework. EWRS = Early Warning Response System; MS = messaging system; DSN = disease surveillance network; EWGLI = European Working Group for Legionella Infections; EISS = European Influenza Surveillance Scheme; BSN = Basic Surveillance Network; EMEA = European Agency for the Evaluation of Medicinal Products; EFSA = European Food and Safety Authority; WHO-OVL = Outbreak Verification List; OIE = Office International des Epizooties (World Organization for Animal Health); FAO = Food and Agriculture Organization; EU = European Union; and Enter-net is an established and thriving EU-wide network for the laboratory-based surveillance of human Salmonella and Verocytotoxin-producing Escherichia coli (VTEC) infections. SOURCE: Based on Kaiser et al. (2006).(2006).
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary FIGURE 2-9 Alerta network. SOURCE: Dr. Carmen Mundaca, Naval Medical Research Center Detachment (NMRCD). Reprinted with permission from NMRCD. because they report disease rates from areas of the country where the MoH does not have a significant presence. The data are captured and displayed in real time on a web-based platform. Several automated outputs are generated so that feedback is given almost immediately to the stakeholders in this process, either by electronic mail or short message service (SMS) messaging to cellular phones. Features include automated outbreak detection via algorithms, graphical representation to assist clinicians, and baseline trends.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary FIGURE 2-10 Data flow from the field. SOURCE: Dr. Carmen Mundaca, NMRCD. Reprinted with permission from NMRCD.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary Discussion A complete evaluation of the ALERTA surveillance system was performed for the period from January 2003 to November 2006, and is the subject of a separate publication (Mundaca et al., 2005). This evaluation focused on three phases: implementation (first year), consolidation (second year), and expansion (third and fourth years). The methods for this evaluation are based on the Centers for Disease Control and Prevention’s (CDC’s) Updated Guidelines for evaluating public health surveillance systems (CDC, 2001). The tasks involved in evaluating this system are adapted from the steps in program evaluation in the Framework for Program Evaluation in Public Health (CDC, 1999), as well as from the elements in the original guidelines for evaluating surveillance systems (CDC, 1988). This assessment was based on information from several data sources, including the main database generated by the system platform, quarterly morbidity reports from the Peruvian navy, outbreak reports, information from Voxiva personnel, focus groups, training evaluations, and surveys applied to stakeholders. Highlights of this evaluation are included below, and include usefulness, sustainability, stability, and flexibility. The Alerta system has been invaluable to the Peruvian navy. Since its implementation through November 2006, 80,747 events have been reported, including 3,789 in 2003; 9,454 in 2004; 25,246 in 2005; and 42,258 through November 2006. The Peruvian navy has embraced Alerta DISAMAR and the culture of epidemiology surrounding it. As one example, the Peruvian military leadership asked all the services for the number of cases of dengue fever in the past year. The navy was the only group that could provide a number and distribution within the week. They searched Alerta DISAMAR’s database and were able to provide the information rapidly. Since this incident, the other branches of the Peruvian military have decided to implement Alerta. Reports such as these have allowed baseline levels of disease to be determined, and for the first time have identified outbreaks of disease in a timely fashion so that diagnoses can be made and interventions enacted. One of the most important questions to ask in evaluating a system is whether that system is doing what it was intended to do. Over the past four years, we have detected more than 31 outbreaks, including diarrhea, dengue, influenza, and tuberculosis. The outbreak of diarrhea depicted below is an example of an outbreak reported using the system (Figure 2-11), and there have been several outbreaks of acute respiratory infections that have initiated outbreak responses at recruit training camps. One of these identified outbreaks (mumps) led the Ministry of Health (MoH) to conduct active community surveillance that uncovered an ongoing outbreak in the civilian population that mirrored that found in the Peruvian navy. Timely detection of outbreaks of disease allow accurate laboratory diagnoses to be made, and with a firm diagnosis, a viable response can be fashioned
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary FIGURE 2-11 Outbreak of diarrhea as reported by the system. SOURCE: Dr. Roger Araujo, NMRCD. Reprinted with permission from NMRCD.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary that hopefully will attenuate the outbreak. The Naval Medical Research Center Detachment (NMRCD) has been able to marry Alerta to molecular and microbiologic diagnostics in a number of these outbreaks, including the use of rapid antigen detection testing for influenza. In addition to outbreak response, we have also provided training in basic epidemiology and more advanced field epidemiology. We have trained more than 600 public health personnel in the Peruvian navy in basic epidemiology and the use of this electronic disease surveillance system. Throughout South America, we have also trained more than 1,300 epidemiologists in the basics of outbreak detection and management. The objectives for these courses and the entire curriculae in Spanish and English are available at no cost on the Web (Lescano et al., 2007). The following attributes of the Alerta system were included in the evaluation process: Simplicity: Description of the data flow; estimated time for the reporter to collect information and analyze the data; staff training requirements; and time spent on the maintenance of the electronic platform. Flexibility: Number of reporting sites added per year; cost and time required to add new sites; ability to add new diseases to the reporting template. Data quality: Reporting rate (percentage of sites that report per total number of sites); percentage of complete reports; error rate (number of errors/ number of reports); error rate per site (number of errors/total number of sites per week). Acceptability: Personnel surveys after training courses; number of personnel who report per site; mean time after training to achieve a timely report. Representativeness: Coverage (percentage of Naval population covered by the system); characteristics of the population. Timeliness: Percentage of sites that report on time and percentage of outbreaks detected on time; average of days to report. Stability: Number of system failures; percentage of time that the system is fully operational; actions involved with repairs in the system. Sustainability: Joint responsibilities; relationship with the Peruvian navy; incentives; costs assumed by each part; problems and requirements to sustain the system. Overall, the Alerta electronic disease surveillance system has been embraced by the Peruvian navy and has transformed public health preparation and response in this population. Both the Peruvian navy and the NMRCD laboratory have contributed personnel, resources, and significant time to ensure optimal performance. The implementation of this system has not been without pitfalls, and many challenges persist. However, the significant progress illustrates how horizontal partnerships and small projects can generate measurable improvements in epidemiologic capability.
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary This quote from a U.S. navy physician sums up the experience in Peru: The introduction of Alerta has led to early outbreak identification/response, timely case management, and increased review of clinical procedures within reporting units… [It is a] working model for similar larger scale international programs Alerta is a simple, near real-time disease surveillance model for countries in all stages of communications technology development (Lescano et al., 2003). Clearly, to respond to and control a potential pandemic, all regions of the world need fully functional public health systems. These systems require careful networking of many components, including reliable disease surveillance, accurate local diagnostics, rapid medical response capability, and fluid cooperation and communication among local and international partners. Some components of successful public health strategies are present in the U.S. Department of Defense Global Emerging Infections Surveillance and Response System (DoD-GEIS). This system is a decade-old DoD program initiated in response to President Clinton’s directive in 1996 that mandated the development of a global system to track, control, and respond to potential pandemic infections. It generated, among other things, the electronic disease surveillance system described above (White House, 1996). GEIS serves as just one component of a growing network of public health assets that are increasingly being used to control infectious diseases with pandemic potential, complementing many global public health community efforts (Chrétien et al., 2006). The Alerta model implemented in Peru has a number of dimensions that have contributed to its success: Committed leadership in all parties; A regulatory regime that specified reporting requirements; A practical use of information technology that maximized the use of available telecommunications and computing infrastructure; Real-time data collection from points of service and automated reports and notification; Live database for continuous analysis and investigation; Links to laboratory and investigation capacity; Training and support of a distributed network of clinicians and other health workers; and Mobile technology accessible to virtually everybody in Peru—if not individually then through a Navy command with cell phones and Internet access. The approach that was developed and tested in Peru is now being expanded with support from the U.S. DoD Southern Command to five neighboring countries: Bolivia, Colombia, Ecuador, Paraguay, and Uruguay. In addition, Voxiva is part of a public–private partnership with the GSM Association, the largest asso-
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Global Infectious Disease Surveillance and Detection: Assessing the Challenges—Finding Solutions: Workshop Summary ciation of mobile phone operators (more than 650 mobile phone operators and 2 billion subscribers worldwide) to extend the benefits of this network in service to public health. Hopefully this can provide not only a model of working in the field, but also a model of cooperation between public and private entities. Acknowledgments The results reported derive from the common vision and hard work of a number of individuals in the Peruvian and U.S. navies and Voxiva as well as the support of the DoD-GEIS program. Key individuals include Drs. Carmen Mundaca, Roger Araujo, Tanis Batsel, Rafael Elgegren, Ernesto Gozzer, Patrick Kelley, Andres Lescano, Monica Negrete, and Mario Ortiz. REFERENCES Altizer, S., A. Dobson, P. Hosseini, P. Hudson, M. Pascual, and P. Rohani. 2006. Seasonality and the dynamics of infectious diseases. Ecology Letters 9(4):467-484. Baker, M. G., and D. P. Fidler. 2006. Global public health surveillance under new international health regulations. Emerging Infectious Diseases 12(7):1058-1065, http://www.cdc.gov/ncidod/EID/vol12no07/pdfs/05-1497.pdf (accessed May 15, 2007). Bloom, R. M., D. L. Buckeridge, and K. E. Cheng. 2007. Finding leading indicators for disease outbreaks: Filtering, cross-correlation, and caveats. Journal of the American Medical Informatics Association 14(1):76-85. Brownstein, J. S. 2006. HealthMap: Global Disease Alert Mapping. Presentation at the Institute of Medicine Forum on Microbial Threats, Washington, DC, December 12-13. Brownstein, J. S., H. Rosen, D. Purdy, J. R. Miller, M. Merlino, F. Mostashari, and D. Fish. 2002. Spatial analysis of West Nile virus: Rapid risk assessment of an introduced vector-borne zoonosis. Vector Borne Zoonotic Diseases 2(3):157-164. Brownstein, J. S., T. R. Holford, and D. Fish. 2003. A climate-based model predicts the spatial distribution of the Lyme disease vector Ixodes scapularis in the United States. Environmental Health Perspectives 111(9):1152-1157. Brownstein, J. S., T. R. Holford, and D. Fish. 2004. Enhancing national West Nile virus surveillance. Emerging Infectious Diseases 10(6):1129-1133. Brownstein, J. S., K. P. Kleinman, and K. D. Mandl. 2005a. Identifying pediatric age groups for influenza vaccination using a real-time regional surveillance system. American Journal of Epidemiology 162(7):686-693. Brownstein, J. S., K. L. Olson, K. P. Kleinman, and K. D. Mandl. 2005b. Effect of site of care and age on timeliness and accuracy of syndromic surveillance data [Abstract]. Morbidity and Mortality Weekly Report 54(Suppl):184. Buehler, J. W., R. S. Hopkins, J. M. Overhage, D. M. Sosin, and V. Tong. 2004. Framework for evaluating public health surveillance systems for early detection of outbreaks: Recommendations from the CDC Working Group. Morbidity and Mortality Weekly Report 53(RR-5):1-11. Butler, D. 2006. Disease surveillance needs a revolution. Nature 440(7080):6-7. Captain, S. 2006. Get your daily plague forecast. Wired News, http://www.wired.com/science/discoveries/news/2006/10/71961/ (accessed April 23, 2007). Cash, R. A., and V. Narasimhan. 2000. Impediments to global surveillance of infectious diseases: Consequences of open reporting in a global economy. Bulletin of the World Health Organization 78(11):1358-1367.
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