About the Authors

Vernon J. Lee

vernonljm@hotmail.com

Affiliations Biodefence Centre, Ministry of Defence, Singapore, Singapore, Centre for Health Services Research, National University of Singapore, Singapore, Singapore, Department of Epidemiology and Public Health, National University of Singapore, Singapore, Singapore, National Centre for Epidemiology and Population Health, Australian National University, Canberra, Australia

Chi Hsien Tan

Affiliation Biodefence Centre, Ministry of Defence, Singapore, Singapore

Jonathan Yap

Affiliation Biodefence Centre, Ministry of Defence, Singapore, Singapore

Alex R. Cook

Affiliation Department of Statistics and Applied Probability, National University of Singapore, Singapore, Singapore

Pei-Jun Ting

Affiliation Defence Medical and Environmental Research Institute, DSO National Laboratories, Singapore, Singapore

Jin-Phang Loh

Affiliation Defence Medical and Environmental Research Institute, DSO National Laboratories, Singapore, Singapore

Qiuhan Gao

Affiliation Biodefence Centre, Ministry of Defence, Singapore, Singapore

Mark I. Chen

Affiliations Department of Epidemiology and Public Health, National University of Singapore, Singapore, Singapore, Department of Clinical Epidemiology, Tan Tock Seng Hospital, Singapore, Singapore

Wee Lee Kang

Affiliation Headquarters Medical Corps, Singapore Armed Forces, Singapore, Singapore

Boon Huan Tan

Affiliation Defence Medical and Environmental Research Institute, DSO National Laboratories, Singapore, Singapore

Paul A. Tambyah

Affiliation Department of Infectious Diseases, National University Health System, Singapore, Singapore

Competing Interests

The authors have read the journal's policy and have the following conflicts: VJL has received unrelated research support from GSK. PAT has received research support and honoraria from Baxter, Adamas, Merlion Pharma, and Novartis as well as travel support from Pfizer and Wyeth and sits on the boards of the Asia Pacific Advisory Committee on Influenza and the Asian Hygiene Council. ARC has received unrelated research funding from the National University of Singapore. The rest of the authors declare that we do not have any conflict of interests, financial or otherwise, in this study. VJL and ARC are academic editors of PLoS One. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: VJL JY WLK BHT. Performed the experiments: VJL JY PJT JPL QG BHT. Analyzed the data: VJL CHT JY ARC MIC PAT. Contributed reagents/materials/analysis tools: VJL ARC PJT JPL BHT. Wrote the paper: VJL CHT JY ARC.