About the Authors

Samantha Cook

Affiliation Google, Inc., New York, New York, United States of America

Corrie Conrad

cconrad@google.com

Affiliation Google, Inc., London, United Kingdom

Ashley L. Fowlkes

Affiliation Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America

Matthew H. Mohebbi

Affiliation Google, Inc., New York, New York, United States of America

Competing Interests

Yes, the authors have the following competing interest. This study was supported by funding from Google Inc., and three of the authors (SC, CC, MM) are employees of Google Inc. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials, as detailed online in the guide for authors.

Author Contributions

Conceived and designed the experiments: SS CC AF MM. Performed the experiments: SC. Analyzed the data: SC CC AF MM. Wrote the paper: SC CC AF MM. Designed the software used in analysis: SC.