Next flu season, mining Internet sites such as Facebook, Twitter, and Google news may provide a faster way to track the spread of H1N1 than reports from official agencies like the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). That’s the idea behind a new generation of disease surveillance tools, including HealthMap, an interactive online system that trawls the Internet for news, both formal and informal, tracking a virus virtually in real-time.
During the global spread of pandemic influenza A (H1N1) last year, HealthMap was able to pick up one of the earliest reports of the disease, well before the outbreak was confirmed by government agencies. Researchers kept the system running throughout the 2009 flu season and found that, on average from country to country, there was a 12-day lag period between informal reports of suspected H1N1 cases and formal confirmations of the virus. After the last wave of H1N1 outbreaks ended, researchers analyzed their data and found that lag periods coincided with a country’s gross domestic product (GDP) - the wealthier the country, the faster the response. The results of their analysis are published in the current issue of The New England Journal of Medicine.
John Brownstein, assistant professor at Children’s Hospital Boston and co-founder of HealthMap, says last year’s H1N1 pandemic was an unprecedented opportunity to test the Internet as a dynamic resource for tracking a particularly fast-spreading disease. At the height of the pandemic, the Internet was flooded with minute-by-minute reports from informal sources like news outlets, blogs, and other websites, well before official agencies could confirm suspected cases. “H1N1 in general was maybe a wake-up call in terms of our capability of dealing with [an] influx of data in an emerging pandemic,” says Brownstein.
Today the WHO and the CDC are using HealthMap every day to help determine how to better track and handle a future H1N1outbreak. HealthMap also monitors the spread of 200 other diseases, such as dengue fever and foot-and-mouth disease. Brownstein’s team recently launched an iPhone application that personalizes HealthMap for a given user. The application uses global positioning to flag outbreaks in one’s area. Both the website and the iPhone app let users type in any flu cases they know of, or any symptoms they may be suffering–information Brownstein can also use to follow the disease.