Tracking the Flu
Mark S. Smolinski, MD, MPH
By May 11, 2009, a swine flu detected just two months earlier in an outbreak in Mexico and the United States had spread to 30 countries raising the threat level to 5 on the global flu scale. On June 11, 2009, the director-general of the World Health Organization further elevated it to level 6: a flu pandemic. While alarming, this should not have been a complete surprise as leading scientists have, for years, been foretelling a flu pandemic was "not a matter of if, but when."
Swine flu is initially showing us its ability to spread, while fortunately, not yet baring its ‘teeth.' Maybe it hasn't cut teeth yet, but it does have a name: novel influenza A, or H1N1. While some may take solace in its low lethality, the speed alone in which this single virus traversed the globe is impressive. But what do we really understand about the spread of flu?
We can learn a great deal from this particular moment in history and perhaps even change the story that will be told of the influenza pandemic of 2009. We live in the day of 24-hour media, Facebook and Twitter, email, texting and all that the World Wide Web has to offer. Are we doing all we can to learn from this influenza pandemic now to be better prepared for the next, perhaps more deadly, wave? The answer, in part, may lie hidden in the spinning wheels of our social constructs.
Public and private efforts can be synergistic when looking to this new age of information and technology to detect the spread of flu. For example, Google Flu Trends is built on the close relationship between how many people search for flu-related topics (query counts) and how many people actually have flu symptoms. Google engineers compared query counts with historical public health flu surveillance systems and found that many search queries tend to be popular exactly when flu season is happening. By using aggregated Google search data, Google Flu Trends can estimate how much flu is circulating in different states and countries around the world. In urgent response to the swine flu outbreak in Mexico, Google launched an experimental Google Flu Trends Mexico without benefit of historical flu data.
Google Flu Trends Australia exemplifies the strength of public/private synergy. Google used historical influenza-like-illness (ILI) data from the Victorian Infectious Diseases Reference Laboratory (VIDRL), the state's largest public health reference laboratory for Google Flu Trends Australia . Public health researchers in Australia are now using Google Flu Trends Australia and Google Trends as comparison tools for their own pilot online health surveillance system to detect epidemics of influenza.
With Google Trends and Google Insights for Search, anyone can compare the world's interest to topics of their choosing. Google Trends analyzes a portion of Google web searches to compute how many searches have been done for the terms you enter, relative to the total number of searches done on Google over time. Google Trends also shows how frequently topics have appeared in Google News stories, and in which geographic regions people have searched for them most. Google Insights for Search provides search volume patterns across specific regions, categories, time frames and properties.
Other early detection efforts were discussed in a recent GLOBAL HEALTH article (Issue 2, Spring 2009) by Kumanan Wilson and John Brownstein, including HealthMap which automatically scans 20,000 news sources every hour to aggregate and disseminate information on emerging diseases on a free map on the web. The Global Public Health Intelligence Network (GPHIN) and the International Society for Infectious Disease Program for Monitoring Emerging Diseases (ProMED) have the added value of disease specialists as moderators to assist in validating early reports .
While Google Flu Trends can help predict flu activity, it cannot replace official influenza surveillance because it does not provide the critical information that public health needs: You.
All public health is local. The spread of influenza is related to our social constructs and within them to our religious and cultural practices, our social networks, our public health preparedness, indeed our world. Flu can spread through communities at any gathering, in health clubs, at the movies, in the workplace and at school. Early alerts and community health recommendations are only as effective as their ability to incite protective action on the ground.
Public health surveillance is about finding cases, confirming with laboratory tests, implementing control measures, and making recommendations for public health safety and security. No self-reporting or proxy illness system can ever replace the public health need to verify an outbreak. Innovative surveillance systems, however, can complement official systems and perhaps, someday, work in unison for the earliest possible threat detection.
The present and future of infectious disease surveillance requires earnest engagement of the ‘public' in public health. It means utilizing the social constructs that often spread disease to be part of the solution for monitoring its spread, demonstrating the effectiveness of community control measures, and educating each other. It may also entail leveraging the use of electronic media to enhance the public's participation.
Any stigma placed on a disease outbreak early in its course can drastically alter its fate. Bugs don't discriminate, people do. Look no further than HIV. Thirty years later, social oppression and HIV continue to bare their teeth in new populations around the globe. Flu spreads efficiently and quickly into all elements of society as a respiratory pathogen. The world is at risk for flu and we must proceed in unison without the fear of stigmatization, discrimination or neglect.
Delays can have unforseen consequences. David Heymann, assistant director-general for health security and environment at the World Health Organization, illuminated the "window of opportunity" that we almost missed with smallpox eradication. HIV persons would not have been able to be vaccinated for smallpox as it would have overwhelmed their weakened immune systems. Had it not been completed just prior to the HIV pandemic, we might never have eradicated smallpox.
Today, we have many individuals with immune systems weakened by chronic diseases, chemotherapy and malnutrition experiencing the flu pandemic in 2009. Historians will have to tell us later whether we ‘missed the window of opportunity' with flu when the next yet unknown infection emerges. What if another new respiratory threat emerges coincidently within this flu pandemic? SARS, after all, was just six short years ago.
SARS had the potential to be a pandemic if not for the heroic efforts of public health and health care communities in the affected countries in synergy with global health partners. It is painfully ironic that greater scientific collaboration necessary to conquer an urgent threat also leads to increase sharing of dangerous pathogens in laboratories around the globe. Scientists are ‘experimenting' with recombinations of influenza strains to advance our understanding of pathogenicity and isolating the virus to assist in diagnostic tests and vaccine development. All are necessary but require enforced biosafety and biosecurity practices.
Remain diligent and vigilant. Every new emerging infectious disease adds to our collective global health burden of prevention, preparedness and control efforts for all infectious diseases. Hantavirus, Ebola, SARS, HIV, bird flu, swine flu are all ‘new' global health burdens bearing on adults who still have many of their parents and grandparents infectious diseases. The world still suffers from polio, malaria, pneumonia, and tuberculosis despite significant advances in science and technology. And our grandparents did not have the added burden of drug resistance like today. Indeed, polio is ‘this close' to being eradicated from the earth. Polio eradication is to global health, what landing a person on Mars is to the space program. It's that important.
But couldn't we learn so much more, so much faster if we just asked people without discrimination "are you sick?" during this critical time of pandemic flu? In the future, perhaps one won't even have to be asked, but we are now in the present. Are we tracking the first flu pandemic of the 21st Century, or are we watching it? History will decide.
[1] Smith, Gavin J.D. et al Origins and evolutionary genomics of the 2009 swine-origin H1N1 influenza A epidemic. Nature. Vol 459; 25 June 2009; doi:10.1038/nature08182.
[2] Jeremy Ginsberg1, Matthew H. Mohebbi1, Rajan S. Patel1, Lynnette Brammer2, Mark S. Smolinski1 & Larry Brilliant1 Detecting influenza epidemics using search engine query data. Nature 457, 1012-1014 (19 February 2009) | doi:10.1038/nature07634; Received 14 August 2008; Accepted 13 November 2008; Published online 19 November 2008; Corrected 19 February 2009.
[3] www.vidrl.org.au/
[5] John S. Brownstein, Clark C. Freifeld & Lawrence C. Madoff. Digital Disease Detection-Harnessing the Web for Public Health Surveillance. The New England Journal of Medicine May 21, 2009.
[6] Institute of Medicine of the National Academies. . Microbial Threats to Health: emergence, detection and response. Mark S. Smolinski, Margaret A. Hamburg, and Joshua Lederberg, eds. 2003, National Academy Press.
Mark S. Smolinski is a public health disease surveillance and response expert at Google, a.k.a. the ‘threat detective'. Mark is currently working for Google.org in Southeast Asia.
We must share scientific evidence and useful information for the people at large more effectively especially in view of incorrect and misleading messages being sent on emails and other communication
— Dr Rajesh Gopal on 2009-08-18