Internet Search Limitations and Pandemic Influenza, Singapore
Figure. Number of Google searches conducted for “influenza” (black lines) and “H1N1” (gray lines) compared with number of acute respiratory infections (ARI, gray bars) reported in government clinics, Singapore, 2009. During the outbreak of pandemic (H1N1) 2009, Google search activity surged in response to newsworthy events (the World Health Organization [WHO] alert, first importation and unlinked local case, release of vaccine) but dropped substantially by the time most infections occurred in August. Other search patterns, such as for “swine flu” and simplified Chinese language terms for swine flu and influenza, were similarly disassociated with actual disease incidence.