Perhaps the greatest challenge for the use of the approach described here is the same that applies across surveillance modalities: the same geographic locations that lack public health resources to control dengue, and to perform traditional surveillance, are likely to lag in access to the Internet as well. Nonetheless, the application of web-query based monitoring to a major and growing health threat in the developing world represents an important step forward. The ability to inexpensively and reliably maintain situational awareness of dengue activity will be welcomed by those charged with the public health response.