Before revision:  The infection ratio out of the US population is estimated to be 0.53\%, implying a case mortality rate at 2.85\% which is close to the 3.4\% suggested by the WHO  .
After revision:  The infection ratio out of the US population is estimated to be 0.53\%, implying a case mortality rate at 2.85\% which is close to the 3.4\% suggested by the WHO in Mar 2020. Towards the end of the summer of 2020, the overall infection ratio of the US rises to 2.49\% while the case mortality decreases to 2.09\%, and the ratio of asymptomatic cases out of all infected cases reduces from the pre-summer 35-40\% to around 20-25\% .