One big limitation right now is that we're basing estimates on confirmed test positive date as opposed to first onset of symptoms which is a much cleaner signa

One big limitation right now is that we're basing estimates on confirmed test positive date as opposed to first onset of symptoms which is a much cleaner signal. Unfortunately, first onset of symptom data doesn't appear to be collected anywhere in a systematic fashion. See this study from China where the use of onset of symptom data allowed them to estimate R much more accurately: https://twitter.com/XihongLin/status/1236075174069440512 https://twitter.com/XihongLin/status/1236075174069440512 From the official WHO Report, page 7, you can see how recording onset date effectively allows you to "see" a week into the future: https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf https://www.who.int/docs/default-source/coronaviruse/who-chi...