Doubling rate in confirmed cases is closer to 4 days than 3 unless you include only the last week or so. A doubling rate of 6 days in the medium term has also b

Doubling rate in confirmed cases is closer to 4 days than 3 unless you include only the last week or so. A doubling rate of 6 days in the medium term has also been estimated. This will obviously delay the time to reach one million cases. However, confirmed cases are a lower bound for the total number of cases, as cases only get confirmed when evaluated by healthcare personnel. It is not credible that Iran and Italy have 3000 cases each, when lots of tourists returning from there have been diagnosed. Did they just randomly bump into one of the 3000 in a country of millions? Uncertainties aside, the model of exponential growth is sound. Disease spread follows exponential growth until it hits an inflection point, either due to running out of viable hosts or due to quarantines and other countermeasures reducing the transmission rate per infected below 1. China forcibly caused this inflection on February 4th, by essentially stopping their economy through strict quarantines. A doubling rate of 4 days yields 1 million infected globally on the 29th of March, and that's what we'll get unless the transmission rate somehow falls before then. Plenty of assumptions in that statement though.