U.S. Flu Forecasts --- 2010 Week 4 (Produced 28 January)

Regional Influenza Activity for week 4 (ending 30 January)

2010 Week 4 (nowcast)


Color coding is based on region-specific baselines.
Green and yellow: below baseline; orange: between baseline and 1.5 times baseline;
red: above 1.5 times baseline; dark red: above 3 times baseline; very dark red: above 6 times baseline.

1 Summary for Week 4 (Produced 28 January)

2 Current Influenza Activity

3 Expected Influenza Activity

Historically, there tends to be an increase in ILI% in the last three weeks of the year, and then again from week 3 to 6 in the new year. This amounts to 20% each week.

4 Flu Season Forecasts of Influenza Activity

The scenarios have not been updated, and are as in the week 38 report.

The dynamic model M2 describes normal flu seasons quite well, but is inappropriate during pandemic flu. For that reason, scenarios are reported.

The one-year ahead forecasts use the average nowcasts for week 37 and 38 as the starting point for forecasting. Then three assumptions are used to capture pandemic flu activity:

Note that the dynamics in the model effectuates a moderating effect after a longer period of very rapid increase. If these assumptions hold, very high levels of ILI% should be expected.

5 References and links

6 Archive


The results reported here are based on forecast, and are therefore uncertain. These results are my personal opinion, based on extensive modeling, and not endorsed by either the CDC or Google.

Jurgen A. Doornik, University of Oxford, UK