About CDC’s Flu Forecasting Efforts
Influenza (flu) places a significant disease burden on the U.S. population each year, but the magnitude and timing varies from season to season, making the annual impact difficult to predict at the beginning of each season. Flu forecasting can change that by predicting in advance when the start, peak, and increases in flu activity will occur. Unlike CDC’s traditional influenza surveillance systems, which measure influenza activity after it has occurred, flu forecasting offers the possibility to look into the future and better plan ahead, potentially reducing the impact of flu.
CDC’s efforts with forecasting began in 2013 with the “Predict the Influenza Season Challenge”, a competition that encouraged outside academic and private industry researchers to forecast the timing, peak, and intensity of the flu season. Each influenza season since then, flu experts within the Influenza Division have worked with CDC’s Epidemic Prediction Initiative (EPI) and external researchers to advance flu forecasting. CDC provides forecasting teams data, relevant public health forecasting targets, and forecast accuracy metrics evaluated against actual flu activity while each team submits their forecasts based on a variety of methods and data sources each week. During the 2018–19 season, CDC expects forecasting teams to provide over 30 national-level forecasts each week.
While significant progress has been made in the years following the initial competition, forecasting flu remains challenging. Flu viruses are constantly changing, and every flu season tends to be different from the one before it. CDC and participating teams continue to collaborate to identify the best data, methods, and practices for forecasting in order to support the advancement of the science of flu forecasting, improving its ability to inform public health action in the future.
As part of the forecasting initiative, CDC has developed, through EPI, the “FluSight” flu forecasting website, which facilitates the real-time sharing and visualization of weekly flu forecasts. Visitors to the site can view current and past forecasts throughout the flu season for the start and peak week, peak intensity, and the near-term activity at the national, regional, and state level. ILINet data are generally updated every Friday, and forecasts are generally available by Tuesday. This site also hosts forecasting challenges for flu-associated hospitalizations. Implementation of the FluSight website was funded by the HHS Idea Lab Ignite Acceleratorexternal icon, which supports new governmental projects with resources and other forms of assistance, and CDC’s Center for Preparedness and Response.