11 June, 2010

HealthMap FIFA World Cup Surveillance

Visit our special surveillance page for the World Cup!

As soccer/football fans turn their attention to South Africa, HealthMap is watching for signs of outbreaks besides World Cup Fever. Teams and fans will be travelling great distances, and their local germs may be hitching a ride. This year's measles outbreak in British Colombia has been attributed to visitors to the Vancouver Olympics. Previous mass gatherings have seen more serious dispersion of disease. For example, Saudi Arabia saw an outbreak of meningococcal meningitis among pilgrims to the Hajj in 2000.

To provide early warning of highly contagious or dangerous disease threats, BioDiaspora and HealthMap have teamed up to increase infectious disease surveillance of the most common countries of origin for travelers to South Africa in June. BioDiaspora studies airline passenger travel to predict patterns of emerging infectious diseases. They have analyzed airline traffic into South Africa and determined the most common countries of origin for travelers.

HealthMap has created additional surveillance feeds in English and Arabic for the top 30 cities of origins. Our normal surveillance feeds utilize an automated text-processing system, which evaluates news stories for disease and location of outbreaks. We have broadened our search terms to improve our ability to identify even vague reports of illness. Our curation team is evaluating the alerts as they come in before allowing them to go to the map. If you are interested in the details of the system, please check out our article in the Canadian Medical Association Journal where we describe our earlier surveillance efforts for the Vancouver Olympics.

Travelers can also encounter new diseases while they travel. South Africa is in the midst of a Rift Valley Fever outbreak. This disease is carried by mosquitoes and generally affects livestock, though humans can be infected as well. At least 166 people have been infected (mostly individuals with direct contact with livestock) and 15 have died. In addition to our regular surveillance efforts, ARGUS has shared their dataset of reports on the outbreak.

Visit http://healthmap.org/fifa/ to see disease alerts for the areas around the top 30 cities, alerts for the 32 teams playing at the World Cup, and Rift Valley Fever alerts in South Africa (including data contributed by ARGUS).

Enjoy the World Cup!!

The HealthMap Team

08 June, 2010

HealthMap New England Journal of Medicine Publication

The HealthMap team recently published Information Technology and Global Surveillance of Cases of 2009 H1N1 Influenza in the New England Journal of Medicine (NEJM). The online paper includes three interactive figures* and demonstrates how informal data can be used to understand epidemiological trends of infectious diseases.

(*Figure 1 shows the worldwide spread of the H1N1 virus, Figure 2 shows a timeline of informal reporting of cases worldwide, and Figure 3 shows the relationship between GDP and time lag between suspected and confirmed case reports)

During the 2009 H1N1 influenza pandemic, nontraditional surveillance sources such as Internet news sources provided new public health data. Collectively, these sources overcame certain limitations of traditional surveillance systems, including reporting delays, inconsistent population coverage, and a poor sensitivity to detect emerging diseases. In May 2009, in collaboration with NEJM and as part of the NEJM’s H1N1 Influenza Center (http://h1n1.nejm.org), HealthMap created an H1N1 interactive map (available at www.healthmap.org/nejm) displaying these reports to enhance the situational awareness of public health professionals, clinicians, and the general public regarding the global spread of 2009 H1N1 influenza infection. Visitors to the site could filter reports according to suspected or confirmed cases or deaths and view a chosen time interval to show the spread of disease. During the two major waves of the H1N1 pandemic, HealthMap collected more than 87,000 reports from both informal and official sources (43,738 reports during the first wave of infection, from April 1 to August 29, 2009, and 43,366 reports during the second wave of infection, from August 30 to December 31, 2009). These reports formed the dataset used in the analyses of this latest paper.

Overall, the 2009 H1N1 influenza pandemic presented an important test of new disease-surveillance systems. The use of data that were collected, coded, and analyzed through the NEJM’s HealthMap system shows how such systems, which were built largely around readily available informal sources, can provide both early warnings and an ongoing operating picture of the patterns of disease spread.

Citation for the publication can be found here.