Doubling Time

Doubling time is a logarithmic calculation of the speed of cumulative incidence of new confirmed COVID-19 cases in Chicago since the 2nd surge began (October 5, 2021).

This graph answers the question: If the growth of the last 7 days continues into the future, how many days until the number of cumulative cases double? The longer it takes to double, the slower the growth of the epidemic. Upward slopes describe growth that is slowing (good news!) and steeper slopes are slowing faster (better news!).  Downward slopes describe growth that is increasing. 

Case counts are based on lab results with known specimen collection date. To adjust for reporting delays, a 5-day lag is used (ie, the chart describes data ending 5 days prior).  (Source: INEDSS)

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