The US Centers for Disease Control (CDC) continuously records the percentage of patients seen in clinics who exhibit influenza-like illnesses (ILI) according to physicians' reports. A patient is said to have an Influenza-like illness if the patient has a fever plus a cough or sore throat.
The traditional clinical verification and distribution of this information takes approximately two to three weeks. This means that we do not have a sense of what is happening now using CDC information, we only have verified information of what happened two or three weeks ago.
Flu Near You
Flu Near You (FNY) is a crowd-sourced participatory disease surveillance system. It gathers information from users about their health in real-time. The plot shows the percentage of ILI-positive reports with respect to the total number of reports.
The data has been smoothed with a spike detection algorithm to remove media spikes. The details of our methodology are presented in: M. S. Smolinski, et al. (2015) Flu Near You: Crowdsourced Symptom Reporting Spanning 2 Influenza Seasons. American Journal of Public Health e1-e7.