Operational Biosurveillance

Standing Advisory: Increasing RSV Transmission With High Pandemic (H1N1) 2009 Co-circulation Presents Potential for Pediatric Medical Infrastructure Strain

[Note the original post date of the below advisory was December 10th.  This was preceded by a state level advisory issued to Texas on December 9th, which triggered a ground truth feedback loop that provided supportive information to expand the advisory.  This advisory remains current as of today and is relevant for the northern hemisphere.]

 

In the past week, Veratect has documented increasing trends of Respiratory Syncytial Virus (RSV) among pediatric cases in Texas, United States.  On 8 December, Veratect issued a report documenting RSV cases above the epidemic threshold in Texas.  Subsequent reports on 10 December within the localities of Houston, San Antonio and Temple corroborated such increases.  Levels of the virus had also been surpassing the epidemic threshold in Kentucky for two weeks, as reported by Veratect on 7 December.  While hospital admissions have been reported in Texas, no public health or health care services strain associated with RSV incidence has yet been noted.

 

The increase in RSV incidence in Texas is not unprecedented, as incidence historically begins to increase in October and peaks between mid December and mid January before declining in February.  Surveillance data from the 2008-2009 season demonstrated a significant increase in positive test results between the end of November and first weeks of December.

 

Despite the expected timing of RSV upward trends, what has not been previously observed is the compound effect from co-circulating pandemic (H1N1) 2009 influenza virus, which has already demonstrated a disproportionate outcome of more severe disease in children.  Texas has been reporting regional influenza activity to the Centers for Disease Control and Prevention (CDC) since the week ending 7 November; however, Veratect sources have cited concern among health care providers that the RSV situation this season could potentially escalate because of the focus on pandemic (H1N1) 2009. 

 

Previous United States Situation Reports issued by Veratect have suggested the potential for additional strain on the emergency department-intensive care unit axis as expected by RSV transmission increase if elevated levels of pandemic (H1N1) 2009 are still present, particularly during the January-February time frame.  Veratect continues to remain vigilant in tracking outcomes of pandemic (H1N1) 2009 co-circulation with RSV and potential effects on the public health sector.

 

[It is likely many areas of the northern hemisphere now have appreciable herd immunity levels for pH1N1, and levels of pH1N1 activity continue to decline in many areas of the US.  It will be interesting to see what level of medical infrastructure strain will be observed this winter.]

Warning of the pH1N1 Threat to Indigenous Peoples

After the realization of a global pandemic involving a novel type A / H1N1 influenza virus (pH1N1) in April 2009, Veratect analysts were concerned about the potential impact of the pandemic as it pertains to vulnerable populations.  Of particular concern was the possibility of severe clinical and sociological impact potentially observed in the indigenous peoples of the Americas.  As was seen during the 1918 influenza pandemic, severe negative impact was seen in the Inuit peoples another indigenous peoples of the Americas, with high case fatality rates documented.  The reasons proposed for this apparent higher risk of adverse clinical outcomes included poor access to medical care and genetic predisposition, among other factors.

 

Veratect first documented an outbreak of suspected pH1N1 virus affecting indigenous peoples in Cauca, Colombia on May 14, 2009.  Then, fatalities were reported in Tocumen and Cascabel, Panama with clinical and epidemiological features consistent with pH1N1 among several different indigenous communities, which included the Kuna who were native to both Panama and Colombia.  On May 29^th, Veratect reported the first confirmed case of pH1N1 in Nunavut Province, Canada, which is a predominantly Inuit population.  On June 1^st, Veratect reported medical evacuations due to pH1N1 from Nunavut to Yellowknife.

 

Then, on June 2^nd, an outbreak of influenza A was reported among the First Nations community in St. Theresa Point in Manitoba Province, Canada.  This required medivac of seven individuals to Winnipeg for treatment as tribal leaders struggled to calm the community.  The same day, Veratect sent an advisory to the American Indian Health Service (IHS) expressing concern about this event and implications for the Inuit peoples and other Native American Tribal Nations.  This was followed up the next day with an advisory sent to the international pediatric critical care community.  Over the course of the next several days, several other First Nations communities in Manitoba were affected.  On June 9^th, the World Health Organization publicly expressed concern about the events involving the First Nations communities in Manitoba, following up with a statement of concern about aboriginal peoples on June 10^th.

 

On June 15^th, Veratect reported the first pH1N1 infections among aboriginal peoples in Australia.  Two weeks later, Veratect reported on high infection rates and adverse clinical outcomes among aboriginal peoples in the Northern and Western Territories and Queensland.  Summary findings were presented by Veratect to the international pediatric intensive care community on July 3^rd.  On July 7^th and 13^th, Veratect shared its findings with an online physician social network managed by Ozmosis.com.

 

On July 19^th, Veratect reached out to the National Congress of American Indians (NCAI) as documentation of indigenous peoples adversely affected by the pandemic increased from Canada, Australia, Panama, and Colombia.  Then, on August 11^th, NCAI invited Veratect to present its findings at the both the Health and Homeland Security Subcommittees of the NCAI Annual Conference in Palm Springs, California, which we did on October 13^th.  We are thankful to NCAI for the opportunity to speak in those important meetings.

 

On December 11^th, the United States Centers for Disease Control and Prevention validated our concerns with its publication in the Morbidity and Mortality Weekly Report (MMWR), “Deaths Related to 2009 Pandemic Influenza A (H1N1) Among American Indian/Alaska Natives --- United States, 2009”. 

 

 

Warning of the 2009 H1N1 Influenza Pandemic: An Operational Perspective

Introduction

 

In the modern era, media remains an important source of infectious disease event reporting.  “Global epidemic intelligence” in the near-real time operational setting has, since the mid-1990s, relied on computer automated online media harvesting capabilities that may or may not include human supervision of translated output.  Examples include the Canadian Global Public Health Intelligence Network (GPHIN)¹, ProMED², and HealthMap³.  Media reports that reach the attention of the World Health Organization (WHO) and the WHO-facilitated Global Outbreak Alert and Response Network (GOARN) are evaluated against the International Health Regulations.  Should criteria be met, then verification that may include an epidemiological investigation or laboratory confirmation is facilitated through communication with GOARN partners that may include subject matter experts deploying to the site in question to obtain samples for laboratory confirmation and conduct an epidemiological investigation. ⁴

 

Those that monitor global media use interpretive techniques more akin to open source intelligence than classic epidemiology.  Key limitations to the use of media include diagnostic ambiguity in the information, experience and credibility of the media source, official government control of media outlets, and contextualization of the information within indigenous cultural baseline.  An ability to gather information across multiple data sources such as human ground networks is essential for signal interpretation, enhancement of credibility, and ultimately, ability to act on the information.  Key to this process is an ability to communicate within a trusted network of professionals to evaluate warning information of varying levels of ambiguity and credibility. ^5,6

 

Until recently, there was little recognition of the need for a professional discipline that utilizes near-real time multi-source information to detect, track, and issue notification of infectious disease events of potential international importance.  Here we present the efforts of multi-lingual analysts at the Veratect Corporation who participated in warning of unusual respiratory disease in April 2009 in Mexico, later discovered through laboratory confirmation to be the first recognized area in the world with rapidly transmitting novel swine influenza (H1N1), that evolved into the first pandemic since 1968, now known as pandemic (H1N1) 2009.

 

Methods

 

Veratect Corporation currently maintains two operations centers staffed with multi-lingual analysts who collect raw information in 28 native vernacular languages and are highly trained in culturally sensitive interpretation of reporting behavior and social responses to infectious disease events, crises, and disasters.  These analysts draw upon multiple sources of near-real time information that includes online media harvesting.  For signal validation purposes, Veratect is confidentially partnered with more than 14 organizations that provide direct ground observations in 238 countries.  The model of event detection and verification follows that of the WHO GOARN. ⁵

 

In the interpretation of raw information, analysts are trained on proprietary grounded taxonomies⁷ that map the socio-cultural context of an infectious disease event.   As analysts evaluate information in the native vernacular language, they assess the described event for whether it is associated with indicators of a routine occurrence of disease (an “event”); whether time-sensitive, non-routine organized decision making is occurring in response to disease where such decisions may affect a local community’s activities of daily living (a “crisis”) ^8-10; or whether perceived failure of crisis mode decision making has occurred with subsequent indicators of community disintegration (a “disaster”) ^11-16.  Analysts working with different cultures have become accustomed to locally-relevant nuances in reporting behavior, and changes in both the behavior in reporting as well as reported social reactions to an infectious disease event are passed internally through a warning notification protocol inspired by the meteorological and natural disaster communities. ⁶ 

 

An online web portal containing Veratect’s up to the minute global infectious disease event detection, tracking, and notification information was provided pro bono to the United States Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO), and the Pan American Health Organization (PAHO, the WHO Regional Office of the Americas) several months prior to the worldwide acknowledgment of pandemic (H1N1) 2009 in Mexico.  Additionally, an email user alert system was created in collaboration with the Global Disease Detection Operations Center (GDDOC) at CDC that provided alert for 1) any infectious disease event assessed by the analyst to have evolved to a crisis or disaster that was 2) within 300 km of an international airport connected to the United States by direct, non-stop air traffic. This algorithm typically presents approximately 1 to 3% (2 to 6 event reports) of our daily operational output for the world to CDC in the form of an email push.

 

Results

 

The detection timeline and notification actions for the H1N1 crisis in Mexico are provided in Table 1 and online data supplement that accompanies this manuscript.  Documentation of the timeline begins with first report of “unusual” respiratory disease (as described by local communities in Mexico) and is carried through to the point of CDC and WHO’s first public announcement of the crisis.

Table 1.  Evolution of Veratect Corporation’s awareness and notification of the Mexico crisis.

Laboratory confirmation of unusual respiratory disease in Mexico was not known until eighteen days into the timeline.  Alerting and notification was based primarily on judgment that asserted local community behavior was unusual both in reactions to the events themselves and how the events were reported by local media.  Specific examples of this include reference to “unusual” respiratory disease, use of the phrase “atypical pneumonia” and reports of an attempted diagnostic rule-out for SARS. “Atypical pneumonia” was a phrase used during the early days of the emergence of SARS in southern Asia in 2002 and 2003 and thus considered a key indicator of interest.

 

Notification protocols were escalated during the timeline, which reflected not only a change in the content of the disseminated warning information but the communication mode.  The first level was posting to an online website in a “pull” model, where viewing of the information depends on the user.  The second level was an automated user alert email that did not provide a listing of all infectious disease crises and disasters throughout the world but rather those within proximity to an international airport connected to the United States by direct, non-stop air traffic.  In this case, the email alert generated on April 16 and 17^th to CDC was due to event proximity to Oaxaca airport, which was located approximately 150 miles from Reforma and connected by direct, non-stop air traffic to Houston, Texas.

 

Notification by phone to CDC was initiated due to awareness of an international request for diagnostic assistance by Mexican authorities, along with reports of possible more widespread involvement of Mexico with “unusual” respiratory disease.  During the conversation, information was presented in terms of what was and was not known.  It was emphasized that while claims of SARS was unlikely, the level of non-routine social concern and disruption and knowledge of an international request for assistance demanded immediate attention.

 

Figure 1a displays the volume of respiratory disease event reporting by Veratect for Mexico and the United States.  Figure 1b displays the volume of respiratory disease event reports in Mexico where the events were in proximity to an airport connected to the United States by direct, non-stop air traffic.  Escalation in the notification protocol was activated before an overt increase in the volume of source reporting of the events in Mexico.  The April 6^th report, available on the Veratect web portal, was derived from 6 sources of information.  The April 16^th report, which was sent by email, was derived from 2 sources of information.  The April 20^th phone call was triggered by communication with a highly trusted individual.

 

[a]

[b]

 

Figure 1.  Respiratory disease reports issued by Veratect during emergence of the H1N1 pandemic.  Notification of unusual respiratory disease in Mexico began on April 6.  Figure 1a displays all Veratect respiratory and influenza reporting for Mexico and US.  Figure 1b displays Veratect reporting for Mexico filtered by proximity to international airports connected to the US by direct, non-stop air traffic; all respiratory disease and influenza reporting for the US also shown.

 

Steps were taken to disseminate information to other organizations and governments due to the realization of a potentially serious, rapidly evolving international public health crisis occurring in proximity to multiple international airports.  None of the domestic U.S. authorities Veratect contacted indicated awareness of these events at the time of notification and requested access to situational awareness.

 

At the suggestion of Colorado state officials, Veratect activated a Twitter account on April 24^th to distribute all real-time updates of the evolving crisis.  The intent was to freely provide situational awareness until official public health organizations had an opportunity to inform the public. By April 29, the Veratect Twitter account was the second most retweeted (reposted) source of information on Twitter.com under the #swineflu trend group behind CDC’s CDCEmergency Twitter account. ¹⁷  Figure 2 displays the increase of public followers of the Veratect Twitter feed, an indicator of public demand for information.  Veratect ceased distribution of information through its Twitter account at 2000 Eastern Standard Time on May 15, 2009.

Figure 2.  Daily public subscription to the Veratect Corporation Twitter account.  Reporting of the H1N1 crisis on the Veratect Twitter account began on April 24.

Discussion

 

A critical aspect of warning is communication within a framework of trust. ¹⁸  This was the single most important aspect of the warning process during the 2009 pandemic of H1N1, where an expression of concern, level of uncertainty, and ultimately, an adjustment of community sensitivity and orientation to a certain issue was achieved.  Communication of Canadian engagement in the Mexico crisis was an essential piece of information to drive sensitization of the US public health and healthcare communities.  Collegial communication with CDC on April 20^th occurred within this framework, and their response was an immediate attempt to coordinate with international colleagues to understand the nature of the crisis in Mexico. ²⁰

 

The evolution of reporting and resolution of uncertainty was similar to the time frame observed during the 1968 influenza pandemic.  In 1968, 28 days passed between initial social awareness of respiratory disease in Hong Kong and 20 days after local recognition of unusual event features, respectively, before laboratory confirmation of the presence of a genetically shifted strain of influenza. ²¹  In the case of the 2009 pandemic of H1N1, 18 days passed between local report of unusual respiratory disease and publicly declared laboratory confirmation of a novel H1N1 strain.  We propose poor reporting and healthcare infrastructure in the initial areas of transmission in rural Mexico, as well as delays in information sharing delayed diagnostic evaluation of the situation.

 

It could be argued that H1N1-positive cases identified in California and Texas was an earlier detection point in the pandemic.  However, H1N1 cases have been identified sporadically in the past for several years.^19,20  We propose the crucial missing piece of information was evidence of rapid, sustained community transmission as observed during the Mexico crisis to enable recognition of an international public health emergency.  Communication of biosurveillance information in a trusted social network of biosurveillance analysts facilitates an integrated situational awareness of public health threats.  Here the process entails bringing together disparate lines of evidence for a fusion of actionable information that enables decision-making.  Information pertaining to laboratory confirmation of H1N1 in California and Texas and that produced by operational biosurveillance analysts is derived from two different professional cultural domains.  Both of these domains are distinct components of an integrated warning system, which will be described below.

 

Collegial communication among professionals in operational biosurveillance occurs through various modes such as email and phone calls.  Conversations occur to share events of concern, collectively resolve discrepancies or ambiguity in the information, elicit different perspectives based on experience and discipline, and ultimately, arrive at a consensus about a particular event.  Such consensus can either be realization an event’s etiology and threat potential is well understood to be of minimal potential consequence, an event’s initial features warrant closer scrutiny and potential ground investigation, or a full escalation of warning notification to multiple parties is required.  The constant processing of indicators, communication of that information, and consultation with professional colleagues has resulted in the emergence of a novel analytic community comprised of different disciplines, experience, and professional perspectives that when combined has enabled realization of a new capability to process a disparate array of biosurveillance information.    This nascent community is comprised of United Nations organizations, Non-Governmental Organizations (NGOs), foreign governments, corporations, academia, and individuals.⁶ Sociologically, this is highly reminiscent of the birth of modern meteorology as a professional discipline.^22,23

 

There is a cultural difference between those that provide early warning and those that respond.  For example, in meteorology the National Weather Service focuses its efforts solely on the detection and warning function, whereas the Federal Emergency Management Agency (FEMA) is more concerned with what happens when and after a storm strikes.  The culture of early warning, and the people drawn to that kind of work, are very different from the response culture of FEMA.  We have found in our experience the culture and people who work in our environment are very different in orientation from the classic epidemiologist or public health officer.  It is similar to the difference in personality between an emergency room physician and a pathologist- both attract very different types of people to the job, but both specialties are essential for patient care. 

 

From a sociological perspective, components of an integrated warning system function together as a social network based on trust.¹⁸  This is true in the biosurveillance operational environment.   Figure 3 displays a schematic of an integrated warning system as it applies to current biosurveillance operations.  Human subject matter experts are required to interpret, process, and communicate signals from detection subsystems such as biosensors, syndromic surveillance systems, open source information, direct clinical observations, or laboratory diagnostic findings.  Fusion of that information, an assessment of credibility and potential threat represented, and consultation with biosurveillance community members are important components of the decision process to generate a given level of warning notification.  Issuance of a warning implies operational sensitization and orientation to the event in question, which requires ongoing monitoring, reassessment for the need to maintain a given state of alert, and communication with biosurveillance community members who themselves may also have a role in translating warnings into response action.

Figure 3.  Integrated biosurveillance warning system, adapted from Mileti and Sorensen (1989). ¹⁸

 

Here we have documented the first instance of using Twitter-based text messaging to warn of an international public health crisis.  The speed with which the pandemic crisis unfolded demanded a dramatically different method of disseminating warning information to a large body of disparate, multi-disciplinary communities.  The dramatic uptake of information by the public, an indicator of confirmation behavior and demand for information was a classic sociological hallmark of a crisis.¹⁸  Veratect analysts monitored Twitter accounts, websites, and public broadcasts by CDC, the U.S. Department of Health and Human Services and the World Health Organization in order to decide the appropriate time to cease the Veratect Twitter feed.  This decision to cease “Twittering” was a specific attempt to encourage public use of credible official sources and avoid confusion in a rapidly complicated information environment. 

 

In a prior report, we emphasized rapid recognition of foreign infectious disease threats and proactive communication of that information was key to mitigating the potential damage sustained by communities that may be connected to that threat by air traffic, cultural diaspora, or commerce. ²¹  Detection and warning activities in the early days of the pandemic (H1N1) 2009 dramatically emphasized this point.  Aside from voluminous road and foot traffic at the border of the United States and Mexico, substantial connectivity via direct, non-stop air traffic between the two countries was noted.  Canada issued a notification to their public on April 22^nd without waiting for laboratory confirmation of samples from Mexico.  This decision was based predominantly on media based reporting of the situation in Mexico and the request by Mexican authorities to Canada for diagnostic assistance (D. Skowronski, personnal communication).  As mentioned in our prior paper, Canada’s proactive use of early warning information for public health crises and disasters represents a potential new standard. ²¹ 

 

The World Health Organization recently noted “the 2009 influenza pandemic has spread internationally with unprecedented speed. In past pandemics, influenza viruses have needed more than six months to spread as widely as the new H1N1 virus has spread in less than six weeks.” ²⁴  When it comes to unusual respiratory disease events, the global community cannot wait for laboratory confirmation to issue public notifications due to the speed with which pathogens are able to translocate.

 

The definition of “early warning” implies time-sensitive dissemination of actionable information.  The “early” component, by its very nature, is associated with a degree of false positives and sensitivity that requires balance with the receiving community of users in terms of their tolerance levels for frequency of notification and operational resources to verify information within their own network.  The “warning” component implies some form of analytic process has occurred to bring the report in question to the attention of a resource-constrained user community. This balance, from an operational viewpoint, is best achieved with trained professionals serving as intermediates between raw information and decision makers.

 

Conclusion

 

We have suggested a robust analytic discipline is required to provide the appropriate cultural context and experience when interpreting the complex interaction between disease hazards and socioeconomic vulnerability and ultimately produce warning information.  In the case of the current pandemic, warning notifications were escalated based on a low volume of source information assessed by experienced analysts.  This is analogous to the comparison of the “astute clinician” versus an automated syndromic surveillance system, where the clinician is a more reliable source of relevant warning information. ^25-27  As with the evolution of medicine and meteorology as professional disciplines, improvements in performance over time is expected with more experience in this new professional domain as well as encouragement of evidence-based practice and scientific research.

 

Acknowledgments

This work was supported through internal funding by the Office of the Chief Scientist, Veratect Corporation.  The authors wish to acknowledge the assistance of Mr. Kyle Geiger and the analysts who participated in the operational functions described in this paper.

 

References

 

1. Mawudeku A, Blench M (2006) Global Public Health Intelligence Network (GPHIN). 7th Conference of the Association for Machine Translation in the Americas; 8–12 August 2006; Cambridge, Massachusetts, United States of America; .Available: http://www.mt-archive.info/MTS-2005-Mawudeku.pdf. Accessed 3 March 2009.

2. Madoff LC, Woodall JP (2005) The internet and the global monitoring of emerging diseases: Lessons from the first 10 years of ProMED-mail. Arch Med Res 36: 724–730.

3. Freifeld CC, Mandl KD, Reis BY, Brownstein JS (2008) HealthMap: Global infectious disease monitoring through automated classification and visualization of internet media reports. J Am Med Inform Assoc 15: 150–157.

4. Formenty P, Roth C, Gonzalez-Martin F, Grein T, Ryan M, Drury P, Kindhauser MK, Rodier G.  Emergent pathogens, international surveillance and international health regulations (2005). Médecine et Maladies Infectieuses 2006 Jan;36(1):9-15. Epub 2005 Nov 23.

5. World Health Organization (2009).  A guide to establishing event-based surveillance.  World Health Organization Regional Office for the Western Pacific Web site.  http://www.wpro.who.int/NR/rdonlyres/92E766DB-DF19-4F4F-90FD-C80597C0F34F/0/eventbasedsurv.pdf.  Accessed July 28, 2009.

6. Wilson JM (2008) Statement by James M. Wilson V, MD, Chief Technical Officer and Chief Scientist, Veratect Corporation Before the House Homeland Security Committee, July 16, 2008.  Available: http://homeland.house.gov/SiteDocuments/20080716143655-63876.pdf.  Accessed July 28, 2009.

7. Bailey KD (1989).  Taxonomy and disaster: prospects and problems.  International Journal of Mass Emergencies and Disasters 7(3):419-431.

8. Rosenthal, Uriel, ‘t Hart, Paul, Charles, Michael T. 1989  “The World of Crises and Crisis Management.” in Coping with Crises: The Management of Disasters, Riots and Terrorism, edited by Uriel Rosenthal, Paul ‘t Hart, and Michael T. Charles.  Springfield: Charles C. Thomas.

9. Gilbert, Claude. 1998.  “Studying Disaster: Changes in the Main Conceptual Tools,”  What is a Disaster?  Perspectives on the Question,  edited by Henry L. Quarantelli.  New York: Routledge.

10. Barton, Allen H. 1969. Communities in Disasters: A Sociological Analysis of Collective Stress Situations.  New York: Doubleday.

11. Dombrowsky, Wolf R. 1998. “Again and Again: Is a Disaster What We Call a “Disaster”?” in What is a Disaster?  Perspectives on the Question,  edited by Henry L. Quarantelli.  New York: Routledge.

12. Horlick-Jones, Tom. 1995. “Modern disasters as outrage and betrayal.” International Journal of Mass Emergencies and Disasters 13:305-316.

13. Kreps, Gary A. 1998. “Disaster: Systemic Event and Social Catalyst.”  What is a Disaster?  Perspectives on the Question,  edited by Henry L. Quarantelli.  New York: Routledge.

14. Oliver-Smith A. 1998. “Disasters, Social Change, and Adaptive Systems.”   What is a Disaster?  Perspectives on the Question,  edited by Henry L. Quarantelli.  New York: Routledge.

15. Stallings, Robert A. 1998.  “Disaster and the theory of social order.” in  What is a Disaster?  Perspectives on the Question,  edited by Henry L. Quarantelli.  New York: Routledge.

16. Coleman, James S. 1966. “Community Disorganization.” in Contemporary Social Problems.  edited by Robert K. Merton and Robert A. Nisbet.  New York: Harcourt, Brace & World, Inc.

17.  Twopular.  Trend Details: #swineflu. http://twopular.com/trend/_swineflu.  Accessed on July 28, 2009.

18. Mileti, Dennis and John Sorensen.  Communication of Emergency Public Warnings, Oak Ridge, TN: Oak Ridge National Laboratory.  ORNL-6609, 1990.

19. Centers for Disease Control and Prevention (2009). Update: Swine Influenza A (H1N1) Infections --- California and Texas, April 2009.  MMWR Dispatch 58(Dispatch):1-3.  April 24, 2009.

20. Centers for Disease Control and Prevention (2009). Swine Influenza A (H1N1) Infection in Two Children --- Southern California, March--April 2009.  MMWR Dispatch 58(Dispatch):1-3.  April 21, 2009.

21. Wilson JM, Iannarone M, Wang C (2009).  Media Reporting of the Emergence of the 1968 Influenza Pandemic in Hong Kong: Implications for Modern-day Situational Awareness.  Disaster Med Public Health Prep. 2009 May 11. [Epub ahead of print]

22.  Friedman RM (1993).  Appropriating the Weather: Vilhelm Bjerknes and the construction of a modern meteorology.  Ithaca: Cornell University Press.

23.  Halford P (2004).  Storm Warning: The Origins of the Weather Forecast.  Gloucestershire: Sutton Publishing Limited.

24.  World Health Organization.  Pandemic (H1N1) 2009 Briefing Note 3 (Revised).  World Health Organization Web site. http://www.who.int/csr/disease/swineflu/notes/h1n1_surveillance_20090710/en/index.html.  Accessed on July 28, 2009.

25. Lewis MD, Pavlin JA, Mansfield JL, O'Brien S, Boomsma LG, Elbert Y, Kelley PW.  Disease outbreak detection system using syndromic data in the greater Washington DC area.  Am J Prev Med. 2002 Oct;23(3):180-6.

26. Espino JU, Wagner MM.  Accuracy of ICD-9-coded chief complaints and diagnoses for the detection of acute respiratory illness.  Proc AMIA Symp. 2001:164-8.

27. Mandl KD, Overhage JM, Wagner MM, Lober WB, Sebastiani P, Mostashari F, Pavlin JA, Gesteland PH, Treadwell T, Koski E, Hutwagner L, Buckeridge DL, Aller RD, Grannis S.  Implementing syndromic surveillance: a practical guide informed by the early experience.  J Am Med Inform Assoc. 2004 Mar-Apr;11(2):141-50. Epub 2003 Nov 21.

 

 

 

 

  

 

 

Timeline of Pandemic H1N1 Warning

Introduction

 

At Veratect, we operate two operations centers based in the United States (one in the Washington, DC area and one in Seattle, WA) that provide animal and human infectious disease event detection and tracking globally.  Both operations centers use a distinct methodology inspired by the natural disaster and meteorology communities.  Our analysts handle information in the native vernacular language and have been thoroughly trained in their discipline, which include cultural-specific interpretation of the information.  We are currently partnered with 14 organizations that provide us with direct ground observations in 238 countries.  We are a multi-source, near-real time event detection and tracking organization with years of experience in this discipline.

 

April 6

 

Veratect reported local health officials declared a health alert due to a respiratory disease outbreak in La Gloria, Perote Municipality, Veracruz State, Mexico.  Sources characterized the event as a "strange" outbreak of acute respiratory infection, which led to bronchial pneumonia in some pediatric cases. According to a local resident, symptoms included fever, severe cough, and large amounts of phlegm. Health officials recorded 400 cases that sought medical treatment in the last week in La Gloria, which has a population of 3,000; officials indicated that 60% of the town’s population (approximately 1,800 cases) has been affected. No precise timeframe was provided, but sources reported that a local official had been seeking health assistance for the town since February.

 

Residents claimed that three pediatric cases, all under two years of age, died from the outbreak. However, health officials stated that there was no direct link between the pediatric deaths and the outbreak; they stated the three fatal cases were "isolated" and "not related" to each other.

 

Residents believed the outbreak had been caused by contamination from pig breeding farms located in the area. They believed that the farms, operated by Granjas Carroll, polluted the atmosphere and local water bodies, which in turn led to the disease outbreak. According to residents, the company denied responsibility for the outbreak and attributed the cases to "flu." However, a municipal health official stated that preliminary investigations indicated that the disease vector was a type of fly that reproduces in pig waste and that the outbreak was linked to the pig farms. It was unclear whether health officials had identified a suspected pathogen responsible for this outbreak.

 

The way we used this information was to simply flag an event as worthy of closer scrutiny and higher awareness, as there was absolutely no proof of true involvement of this company in the outbreak- a proper epidemiological investigation is required to prove such links.

 

Local health officials had implemented several control measures in response to the outbreak. A health cordon was established around La Gloria. Officials launched a spraying and cleaning operation that targeted the fly suspected to be the disease vector. State health officials also implemented a vaccination campaign against influenza, although sources noted physicians ruled out influenza as the cause of the outbreak. Finally, officials announced an epidemiological investigation that focused on any cases exhibiting symptoms since 10 March [1-6].

 

This information was available in our web portal to all clients, including CDC, WHO/PAHO and multiple US state and local public health authorities.

 

We do know, after checking our web site logs, that the Pan American Health Organization, the WHO Regional Office of the Americas, accessed this specific report in our system on April 10th and again on April 11th.

 

 

April 16

 

Veratect reported the Oaxaca Health Department (SSO) indicated that an unspecified number of atypical pneumonia cases were detected at the Hospital Civil Aurelio Valdivieso in Reforma, Oaxaca State, Mexico.  No information was provided about symptoms or treatment for the cases.  NSS Oaxaca reported that rumors were circulating that human coronavirus was spreading at the hospital; sources did not provide any response to these statements from the hospital or health officials.  

 

Laboratory samples were sent to Mexico City for analysis; results were expected to be released sometime next week.  According to NSS Oaxaca, health officials had intensified preventive measures aimed at mitigating further spread of the disease.  Sources reported that the SSO also implemented a sanitary cordon around the hospital [7-8].    

 

This information was pushed to CDC in an email alert notification provided by Veratect on April 16 and again on April 17:

 

"16 Apr 2009 4:14 PM GMT     Respiratory Disease     Detailed     Mexico (Reforma, Oaxaca)  Reforma: Atypical Pneumonia Cases Reported at Hospital", sent at "April 16, 2009 10:08:06 AM PDT" and again at "April 17, 2009 10:08:06 AM PDT" to CDC and at "April 16, 2009 10:27:13 AM PDT" to the California State Department of Health.

 

 

April 20

 

Veratect was urgently asked to provide access to the VeraSight Global platform on 20 April by a client in the US public health community, and indicated they had received word from their counterparts in Canada that Mexican authorities had requested support.  This client speculated whether notification of all southern U.S. border state public health authorities should be done and were confused as to why the CDC had not issued an advisory.  Veratect contacted the CDC Emergency Operations Center to sensitize them about the situation in Mexico. CDC indicated they were already dealing with the crisis of recently detected H1N1 swine influenza in California and possibly Texas.

 

April 21

 

Veratect reported the Oaxaca Health Department (SSO) confirmed two adults died from atypical pneumonia at the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico.  One of the cases was a 39-year-old female; the other case was an adult male of unspecified age.  After the deaths, the hospital established a quarantine in the emergency room due to initial concerns that avian influenza was responsible for the cases.  However, the SSO subsequently stated that neither avian influenza nor coronaviruses, including that which causes severe acute respiratory syndrome (SARS), were the source of infection.  Additionally, the SSO denied the cases represented an epidemic.  According to local sources, the SSO indicated that the atypical pneumonia cases were caused by an unspecified bacterial pathogen and were treatable with antibiotics.  Sources indicated a total of 16 additional patients exhibited signs of respiratory infection; none of these patients exhibited complications.          

 

Veratect sources indicated the 39-year-old female was treated at the hospital for five days before dying on 13 April.  This case was reportedly immunocompromised; in addition to acute respiratory symptoms, she also had diabetes and diarrhea.  The SSO contacted 300 people that had been in contact with the woman; sources stated that between 33-61 contacts exhibited symptoms of respiratory disease, but none showed severe complications.  The SSO characterized the incident as an "isolated case;" they noted that over 5,000 cases of pneumonia occur annually in Oaxaca.

 

Another local source reported the SSO launched surveillance measures in the former residential areas of the two fatal cases and in other targeted geographic areas.  No additional information was provided regarding the second fatal case at the hospital.  

 

Veratect reported that the Oaxaca State Congress Permanent Committee on Health had undertaken an investigation into the cases.  The committee inspected the Hospital Civil Aurelio Valdivieso on 20 April.  The director of the medical school at the University Autonoma "Benito Juarez" de Oaxaca (UABJO), along with other medical academics, publicly requested that national health authorities investigate the cases of atypical pneumonia.  No information was provided indicating that national health authorities plan to investigate the matter.  The director of the medical school also requested the SSO furnish evidence showing that the cases were negative for avian influenza, SARS, and other severe pathogens; his request was echoed by readers commenting on an online user forum.         

 

Veratect also reported the National Ministry of Health issued a health alert due to a significant increase in influenza cases during the spring season in Mexico.  Officials indicated that there have been 14 influenza outbreaks throughout the country.  The most heavily affected states are Baja California, Chihuahua, Distrito Federal (Mexico City), Hidalgo, Tlaxcala, and Veracruz.  Local case counts were not provided.

 

Officials stated that 4,167 probable cases of influenza, 313 of which were confirmed, have been reported throughout the country in 2009.  Case counts for suspected and confirmed influenza cases have tripled in 2009 as compared to the equivalent time period in 2008.  The National Institute of Respiratory Diseases recorded two fatal cases of influenza in 2009, but specific dates and locations were not provided.  

 

Health officials stated they were unsure precisely why the incidence of influenza had increased.  However, they believed the increased presence of influenza B, in combination with influenza A, was a contributing factor.  In response, officials advised anyone exhibiting influenza symptoms to avoid self-medication and seek medical care immediately.  Officials had also enhanced epidemiological surveillance for influenza.  Lastly, health officials had focused efforts on providing antiviral medications and influenza vaccinations to the most vulnerable segments of the population.  According to the Mexican Ministry of Health, 44.3% of the national population was vaccinated against influenza in 2005-2006.

 

Veratect sensitized the International Federation of Red Cross who in turn requested broader access be provided to the Pan-American Disaster Response Unit (PADRU).  Veratect moved to notify several US state and local public health authorities, providing the caveat the situation in Mexico remained unclear due to pending laboratory results.  Veratect reached out to World Health Organization (WHO) operations, informing them the Veratect team was on an alert posture and available for situational awareness support.  They indicated they and their subordinate, the Pan American Health Organization (PAHO) were now aware of the situation but had no further information.  Veratect also extended contact to the British Columbia Center for Disease Control and offered assistance in tracking the events in Mexico.  All contacts indicated laboratory results were pending [9-15].

 

 

April 22

 

Veratect reported the Oaxaca Health Department (SSO) indicated 16 employees at the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico had contracted respiratory disease.  However, the SSO denied these cases were connected to the recently identified cases of atypical pneumonia at the hospital.  No information was provided indicating how many employees work at the hospital or whether the number of respiratory disease cases was higher than average.  The source reported that "fear" persisted among hospital physicians concerning the possible presence of a deadly bacteria or virus circulating in the hospital.  One anonymous hospital employee criticized hospital management as "unfair" for not providing clear information regarding the first fatal atypical pneumonia case.

 

An additional source reported the cause of the atypical pneumonia cases remained unknown; it stated that bacteria or virus could have caused the cases.  In contrast, according to an 18 April report, the SSO indicated that the atypical pneumonia cases were caused by an unspecified bacterial pathogen and were treatable with antibiotics.  The reason for this discrepancy was unclear at this time.

 

The Instituto Mexicano del Seguro Social (IMSS), a national health entity, had now joined the SSO in responding to the cases; reports did not indicate the Mexican National Ministry of Health had joined in the response efforts.  The IMSS extended the sanitary cordon surrounding the hospital.  Patients exhibiting flu-like symptoms would be sent to the hospital’s epidemiology department for further study.  IMSS instructed physicians to hospitalize respiratory disease patients immediately if they meet certain standards for severity of symptoms.  Lastly, the hospital’s emergency room would remain closed for an additional 15 days so that cleaning and preventive disinfection could be carried out.

 

Veratect also reported the Mexican Ministry of Health indicated that an "unusual" outbreak of laboratory-confirmed influenza caused five deaths from 17-19 April 2009 in Mexico City, Mexico.  The deaths occurred at the following three hospitals: el Hospital de la Secretaria de Salud (2), el Institute Nacional de Enfermedades Respiratorias (2), and el Hospital Angeles del Pedregal (1).  According to unofficial sources, the fatal case count was higher than that provided by officials.  There were currently 120 influenza cases hospitalized throughout Mexico City.  National health officials indicated that influenza vaccines were sold out in Mexico City and that they were attempting to acquire additional supplies of the vaccine.  

 

At this point, the Mexican Health Secretary reportedly stated there was no influenza epidemic in Mexico City or throughout the rest of the county.  In response to the cases, the official stated health authorities would launch a public awareness and vaccination campaigns.  He stated that 400,000 vaccines would be administered, primarily to medical staff; it was unclear whether these efforts would be focused on Mexico City or any other geographic area.  Health officials also ordered the provision of special masks, gloves, and gowns for medical personnel that were in contact with influenza cases. 

 

A total of 13 fatal cases of influenza were reported in Mexico City in the past three weeks.  However, several other media sources reported that the 13 deaths were recorded since 18 March 2009; the reason for this discrepancy was unclear.  Sources reported a total of 20 fatal cases of influenza throughout Mexico over the disputed timeframe.  The other cases were located in San Luis Potosí (4), Baja California (2), and Oaxaca (1).  The Director of Epidemiology at the National Center for Epidemiological Surveillance and Disease Control characterized the outbreak as "quite unusual."

 

No information was provided indicating that the strain of influenza itself was unusual.  Rather, several sources indicated that it was "unusual" to record this many fatal influenza cases during this time of year.  Influenza cases normally peak from October to February, while these cases had occurred during Mexico’s spring season.

 

Canada announced a national alert for travelers returning from Mexico with respiratory disease, beginning a campaign of public media announcements. Potentially ill contacts were identified returning from Mexico and isolated in Canada.  Internet blogs begin to spin up.  CDC indicates concern about the events unfolding in Mexico.  Veratect sensitizes the US community physician social network managed by Ozmosis [16-28].

 

 

April 23

 

Veratect reported the Secretary General of the Oaxaca Ministry of Health Workers Union confirmed that a doctor and a nurse from the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico were under observation for suspected "atypical" pneumonia.  This contradicted statements made by the Oaxaca Health Department (SSO) on 22 April that 16 hospital employees contracted respiratory disease, but none of the cases exhibited atypical pneumonia.

 

The union official stated that a review by the Oaxaca State Board of Medical Arbitration indicated that the hospital faced serious difficulties caused by overcrowding; he stated that overcrowded conditions created a "breeding ground" for the spread of various epidemics.  According to the official, the hospital has 120 beds but the number of patients hospitalized had at times surpassed 240.      

 

Other sources reported that the Department of Livestock, Fisheries, Rural Development, and Feed (SAGARPA) declared on 20 April that Oaxaca, Mexico was free of avian influenza.  SAGARPA stated that authorities should remain vigilant in monitoring for the disease among birds. 

 

Canadian local health officials stated that a Rouge Valley resident with influenza-like illness was being monitored at Scarborough Centenary Hospital in Scarborough, Ontario.  The precaution was being taken in accordance with an alert issued by the Ministry of Health asking hospitals to watch for severe respiratory illnesses in travelers returning from Mexico.  Despite the warning, the Ministry had indicated that evidence is not suggestive of a novel pathogen or influenza strain, according to the source.  A representative for the Rouge Valley Health System stated that this case is being monitored related to the alert.  The source did not specifically indicate symptoms or that the person had traveled to Mexico.  No additional information regarding the case, including age or health status, was reported.  

 

The source stated that hospital employees were asking any patients admitted to the hospital if they had recently traveled to Mexico, which according to the source was a popular tourist destination for Durham-region residents.

 

Additional Canadian sources indicated Southlake Regional Health Centre officials treated a patient with influenza-like illness (ILI) who recently returned from Mexico.  The Ministry of Health recently notified Southlake, in addition to health units across the country, that an outbreak of severe respiratory disease was affecting areas of Mexico; ill travelers returning from that region with ILI symptoms were encouraged to be monitored.  Sources did not provide any specific information about the case, including age or current treatment status.  Information regarding the individual’s travel to Mexico was also not provided, including destinations and duration of time in country.

 

The Public Health Agency of Canada (PHAC) noted that an Ontario resident who returned from Mexico on 22 March experienced severe respiratory illness, but has fully recovered and was not considered connected to the current situation.  Veratect recently reported on 30 March that a public official from Cornwall, Ontario was hospitalized with an unknown illness following a trip to Mexico; however, it is unclear if the cases are related, or if this was the case referenced by PHAC officials [29-39].

 

On 23 April, Veratect assessed the situation and noted the following:

 

Affected areas:

 

Oaxaca, Distrito Federal, San Luis Potosi, Baja California

 

Distance to nearest international airport:

 

·      Oaxaca airport, located approximately 150 miles from Reforma, is connected via non-stop air traffic to Houston

·      Mexico City (Distrito Federal) airport is connected via non-stop air traffic to many cities in the US, Canada, Europe and Latin America, with the most outbound traffic to Los Angeles, Frankfurt, Houston, Dallas, and Amsterdam

·      San Luis Potosi airport is connected via non-stop air traffic to Dallas and Houston

·      Mexicali airport in Baja California is connected via non-stop traffic to Los Angeles

·      Veracruz airport is connected via non-stop air traffic to Houston

 

Large mass gatherings:

 

Semana Santa (~April 3 - 12, Palm Sunday to Easter Sunday), which is Mexico’s second largest holiday.  Mexico’s population is approximately 90% Catholic, which results in substantial population migration patterns during this time period.  For instance, in Ixtapalapa (in Mexico City), one million people visit for Semana Santa.  Other well-known sites for the holiday include Patzcuaro, San Cristobal de las Casas (Chiapas), and Taxco.  Veratect notes substantial population migration has just occurred that could facilitate the spread of respiratory disease.

 

Civil Unrest:

 

The recent surge in organized crime and drug-related violence in Mexico, including homicides, kidnappings, extortion, and theft, has disproportionately impacted Mexican states along the Pacific Coast and U.S.-Mexico border.  This factor may confound situational awareness of respiratory disease in Mexico and contribute to problems in epidemiological investigation and response measures.  Baja California is one of five states within this region that currently accounts for more than 75 percent of Mexico's drug-related homicides, and has recorded high levels of drug seizures and police corruption cases. Veracruz, a state with high drug cartel activity in the Gulf of Mexico, has recorded little violence, while the state of Oaxaca to the southwest, recently recorded the assassination of a political party leader. Mexico City, in the center of the country, recently arrested a major drug cartel leader, and recorded few homicides this month. The levels of unrest in Hidalgo, San Luis Potosi, and Tlaxcala, however, are very low, and have not reported a single homicide related to organized crime in the past month.

 

Veratect issues notification to additional public health authorities in two states.  Veratect reaches out to the Pan American Health Organization emergency operations team but is unable to establish contact.  Veratect notes no publicly available English language reporting from ProMED, HealthMap, FluNET, CDC, ECDC, or WHO about the unfolding events in Mexico.  Many of Veratect’s clients, including Canadian, ask why an alert has not been issued by the US to sensitize their healthcare community.

 

April 24

 

Veratect continues to process a dramatic increase in reporting on the situation in Mexico.

 

WHO requests access to the Veratect system.  Veratect is aware of laboratory samples from Mexico are positive for swine flu H1N1, a novel virus.  World media are now aware of the situation in Mexico.  CDC issues a press statement, as does WHO.

 

Veratect notifies the United Kingdom National Health Service NaTHNaC (National Travel Health Network and Centre).  The NaTHNaC website as of April 24^th contained no public announcement of the situation in Mexico.  Response from their senior analyst did not indicate awareness.  Veratect notifies the private US clinical laboratory community and activates a Twitter feed (twitter.com/veratect) to enable more rapid updating of information until WHO and CDC were able to come up to date with their public reporting.

 

 

References

 

1.    Reportan deceso de tres menores; lurgarenos reponsabilizan a empresa; Alerta epidemiologica en Perote por brote de males respiratorios [Death of three children reported; villagers blame company. Perote epidemiological alert for outbreaks of respiratory disease]. La Jornada. 4/5/09. Accessed 4/6/09 at http://www.jornada.unam.mx/2009/04/05/index.php?section=estados&article=025n1est

2.    Realizan barrido sanitario por foco de infección en Perote, Veracruz [Health cordon enacted in Perote due to focus of infection]. SDP Noticias. 4/5/09. Accessed 4/6/09 at http://sdpnoticias.com/sdp/contenido/2009/04/05/369612     

3.    Alerta epidemiológica en La Gloria, Perote por brote de males respiratorios. Acusan a Granjas Carroll [Epidemiological alert in La Gloria, Perote due to respiratory disease outbreak. Carroll Farms Accused]. Zapateando.  4/5/09. Accessed 4/6/09 at http://zapateando.wordpress.com/2009/04/05/alerta-epidemiologica-en-la-gloria-perote-por-brote-de-males-respiratorios-acusan-a-granjas-carroll/

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