Cumulative Query Method for Influenza Surveillance Using Search Engine Data

Dong-Woo Seo   ¹ , MD, PhD ;   Min-Woo Jo   ² , MD, PhD ;   Chang Hwan Sohn   ¹ , MD ;   Soo-Yong Shin   ³ , PhD ;   JaeHo Lee   ^{1, 3, 4, 5} , MD, PhD ;   Maengsoo Yu   ⁶ ;   Won Young Kim   ¹ , MD, PhD ;   Kyoung Soo Lim   ¹ , MD, PhD ;   Sang-il Lee   ² , MD, PhD

¹ Asan Medical Center, Department of Emergency Medicine, University of Ulsan, College of Medicine, Seoul, Korea, Republic of

² Asan Medical Center, Department of Preventive Medicine, University of Ulsan, College of Medicine, Seoul, Korea, Republic of

³ Asan Medical Center, Department of Biomedical Informatics, Seoul, Korea, Republic of

⁴ Brigham and Women's Hospital, Division of General Medicine and Primary Care, Boston, MA, United States

⁵ Harvard Medical School, Boston, MA, United States

⁶ Daum Communications, Search Development Unit, Seoul, Korea, Republic of