By Alyah Khan

The World Health Organization recently estimated that over 40 percent of the world’s population is now at risk for dengue, a mosquito-born viral infection that can develop into a potentially lethal complication called severe dengue. As a result, dengue has become a major international public health concern. However, dengue cases are often underreported and monitoring incidents of the disease is challenging. That’s why companies, governmental organizations and concerned citizens are coming up with innovative ways to track dengue outbreaks.

Search term: Dengue
Google has launched “Google Dengue Trends,” modeled after “Google Flu Trends.” The dengue trends website uses aggregated Google search data to estimate near real-time dengue activity around the world.
Google compared dengue-related search queries with traditional dengue surveillance systems and found that many search queries were popular during dengue season. “By counting how often we see these search queries, we can estimate how much dengue is circulating in different countries and regions around the world,” Google wrote on its site. The trends site provides detailed information on dengue activity in Argentina, Bolivia, Brazil, India, Indonesia, Mexico, the Philippines, Singapore, Thailand, and Venezuela.
Seeing dengue from space
A group of scientists from the French Space Agency (Centre National d'Etudes Spatiales, CNES) and Sanofi Pasteur are also working together on a project to use new satellite imaging technology to map areas at risk for dengue. The joint research project will be piloted in the Caribbean because of its history of severe dengue outbreaks, according to Sanofi Pasteur.
Dengue outbreaks remain difficult to predict, which is why “there is a need to compile a comprehensive dataset of the disease’s spatial and temporal distribution,” Sanofi Pasteur said in a press release.
Reporting dengue in Rio
Meanwhile, residents of Rio de Janeiro in Brazil are taking the fight against dengue into their own hands by creating the website, “Rio sem Dengue” (Rio without Dengue). The site employs the concept of crowdsourcing by allowing citizens to self-report cases of dengue and mosquito focal points. Visitors to the site can see the reports pinpointed on a map and add photos of locations to their reports. Thus far, 559 reports had been submitted to the site and 95 percent of those reports had been verified.

Mapping dengue

In terms of government involvement, the Centers for Disease Control and Prevention in the United States has collaborated with HealthMap to create “Dengue Map.” The map identifies areas of ongoing transmission risk, as defined by CDC, and is based on information from ministries of health, global health organizations, journals and experts. HealthMap collects official and/or media reports of local, regional or imported dengue cases and marks these cases on the dengue map with a red pin linked to the respective reports.
The Dengue Vaccine Initiative provides a similar resource called, “Dengue Watch.” Dengue Watch, like Dengue Map, relies on data from HealthMap. Additional features of the Dengue Watch site include breaking dengue news, information on the disease and links to national dengue data for countries around the world.
The above initiatives demonstrate that keeping up with dengue is an incredibly complex task that requires creative thinking. As we wait for a dengue vaccine, prevention becomes the best way to fight against this disease. But effective prevention can only happen if we know where dengue is occurring and what areas of world are at risk of ongoing transmission. The resources featured here will hopefully continue to improve our ability to keep an eye on dengue.